Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

The fluctuating conditions of Lake Limboto have greatly affected the activities of people living around the lake. The shallowing and narrowing of the lake poses a significant problem to local people’s survival. The lake is predicted to disappear by 2030, which will consequentially lead to a diminishment in the productivity of the lake. This article aims to analyze how the communities around the lake respond in their daily activities to the transformation of the lake and the shocking prediction about its lifespan. This study uses an interdisciplinary approach by integrating multiple fields of study to understand and address the problems regarding this issue. This research comprised a literature review, field survey, and in-depth interview process around the lake. This research relied on the framework of cultural studies to analyze the survival and resilience of the people around the lake, gaining an understanding of their special daily activities. The results of this study show that some people are aware of the lake’s gradual recession, but they have not prepared for it, treating the problem as only a government affair. They continue to live at the lake’s shores, enduring even amidst impoverished conditions.

DOI： 10.3390/su16020704

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Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Artisanal and small-scale gold mining (ASGM) harms the environment and human health, because it requires mercury (Hg). Therefore, this study uses a questionnaire survey to identify the effects of the medical checkup findings, group discussion, and educational seminar on the values of illegal miners and residents in Bunikasih, Indonesia, regarding the environmental and health effects of Hg. Transdisciplinary communities of practice (TDCoP) were formed to pursue alternative livelihoods than illegal ASGM. Environmental pollution after ASGM closure was assessed. The questionnaire showed that respondents changed their views on Hg’s effects and were willing to stop ASGM practices. In an environmental impact assessment study, tea leaf samples were obtained between the ASGM activity location and village housing in two periods during ASGM closure to identify the concentrations of Hg, lead, and arsenic. Their mean concentration values in Period 1 (2) were 0.54 ± 0.14, 0.66 ± 0.09, and 0.34 ± 0.12 mg kg−1 (0.08 ± 0.04, 0.34 ± 0.14, and 0.07 ± 0.06 mg kg−1), respectively, indicating a decrease in environmental pollution. In conclusion, the government-driven cessation of ASGM in the study area shows a reduction in environmental pollution, and the change in the perception of the participants regarding the ASGM and TDCoP approaches help to make these changes permanent.

File： Idham Andri Kurniawan_IJERPH.pdf

DOI： 10.3390/ijerph20176663

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Authorship：Corresponding author   Publishing type：Research paper (scientific journal)   Publisher：EDP Sciences  

Lake Limboto is one of the key lakes with severe siltation, caused by sediment delivered by river currents. This study aims to reduce the impact of sedimentation by controlling erosion with a palm fiber net with mesh dimensions of 5 cm x 5 cm and a thickness of 5 mm. The Palm fibre installation is installed on slopes with erosion potential; each location has a different slope: location 1 has a slope of 40o, location 2 has a slope of 45°, and location 3 has a slope of 50°. With the findings obtained, palm fiber nets erosion control was shown to be effective in repelling erosion. The first site has an 8:3 ratio, the second location has a 5:2 ratio, and the third place has a 1:0.5 ratio, net performance at each location of 42% location 1, 39% location 2, 41% location 3 and 0% at location 4. Differences in soil structure and slope of the slope generate variations in the data acquired from each location.

DOI： 10.1051/e3sconf/202340001019

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Publishing type：Research paper (scientific journal)   Publisher：Universitas Negeri Gorontalo  

Sample of Arenga Pinnata (AP) fibres, ropes and nets were prepared from AP ropes using traditional tools. The ropes and nets were used as agricultural material such as vertical farming of vines (passion fruit, grape, bitter gourd, and melon) in Gorontalo and Japan. The combination of nets and vines acts as green curtain (GC) which. Could mitigate the thermal energy in outdoor as well as indoor buildings. and tested with the deformation rate of up to the point of rupture. To avoid the failure of ropes and nets on supporting the weight of the vines, the Universal Testing Machine Model WDW-50 were used to determine the ultimate tensile forces. While the physical size of the AP fibres, ropes and nets also being measured to confirm the uniformity of the individual ropes and nets

DOI： 10.34312/jpj.v5i1.19433

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Authorship：Corresponding author   Language：Japanese   Publisher：国土交通省北海道開発局  

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Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Potentially toxic elements (PTEs) from natural and anthropogenic activities threaten the environment and human health. The associations of PTEs with natural hazards can be powerful and prominent mechanisms to release PTEs, considerably hastening their multiple contaminations and widespread distribution. This study primarily aimed to investigate the enhanced potential distribution of PTE contaminations (arsenic, lead, and mercury) from coexisting gold mining operations combined with massive riverbank erosion in Indonesia from 2002 to 2022, where soil and water are highly contaminated naturally, using PlanetScope smallsat constellations, Google Earth imagery, and hydrographic datasets. According to the findings, increased barren extents were found because of mining deposits and road network developments. Enhanced natural and anthropogenic PTE runoffs would be transported across two different sub-basins, affecting broader parts of the Bone River. Between 2002 and 2022, 139.3% of river expansion was identified, eroding a maximum of 3,436,139.4 m3 of contaminated soil. Particularly land surfaces were repeatedly transformed from rivers to agricultural lands in the low Bone River, possibly contaminated by fertilizer spills. The combination of PTE potentials from different sources would further exacerbate the contamination level at an estuary. These findings are expected to aid in the timely monitoring of and assuming volumes, rates, and distribution of PTEs from various natural and anthropogenic activities and alert PTE contamination risks to ecosystems and human health. Future work in this area should aim to investigate contamination levels at the estuary, where contaminated materials from both natural and anthropogenic activities are accumulated.

DOI： 10.3390/rs15030861

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Historically, cocoa (Theobroma cacao) has been one of Ecuador’s most important export crops. In the Ponce Enriquez district, artisanal and small gold mining (ASGM), and quarrying account for 42% of economic activities, while agriculture and livestock farming account for 30%, making the analysis of their synergy and interaction key to understanding the long term viability of the different activities. In this study, we evaluated the concentration of potentially toxic metals in different parts of the cocoa plant and fruit, in relation to mining activities within the area. Gold extraction generates pollution, including potentially toxic metals such as mercury (Hg), cadmium (Cd), arsenic (As), copper (Cu), lead (Pb) and zinc (Zn). In order to understand the mobility of these metals within the cocoa plant and fruit, the analysis was conducted separately for leaves, pod, husk and cocoa bean. Concentrations of the target metals in the different plant parts and soil were measured using ICP-MS, and the mobility and risk factors were calculated using the transfer factor (TF) and the risk ratio (HQ). The results suggest that Zn, Cd and Cu are indeed moving from the soil to cocoa leaves and beans. Furthermore, the results show that the concentrations of toxic metals in the different parts of the cocoa fruit and plant, particularly in the cocoa bean, which is used for chocolate manufacture, are not higher than those regulated by FAO food standards, as is the case of Cd, which is limited to 0.2 mg Cd/kg and in the samples analyzed does not exceed this limit. Even though the concentration of these metals does not exceed the safety standard, the presence of these potentially hazardous metals, and the fact they are absorbed by this important local crop, are worrying for the long-term sustainability of cocoa cultivation in the area. Therefore, it is fundamental to monitor the local environment, understanding the distribution of heavy metal pollution, and work with the local authorities in landscape management to minimize the exposure of crops to ASGM pollution.

DOI： 10.3390/ijerph192114369

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Gold mining is a significant strategic sector for local, regional, and national economies. The rapid development of coexisting camp-type artisanal and small-scale gold mining (C-ASGM) and large-scale mining (LSM) accelerates the environmental and health risks associated with mercury pollution; however, transformations of coexisting sites have not been well quantified. This study used remote sensing (the PlanetScope smallsat constellations systems) to investigate the development of coexisting C-ASGM and LSM sites in Gorontalo, Indonesia, from 2019 to 2022. The results show a positive increase in the extent of barren land across all study zones, resulting from a road network construction connecting the southern port to major mining sites. Notably, greater landcover transformations in the C-ASGM sites after 2020 were attributed to the dumping of underground soils excavated using a shaft-mining method. The findings of this study expand our understanding of the rapid development of coexisting mining operations and quantify significant mining-induced environmental changes. These findings are anticipated to assist in timely monitoring and identification of development areas, rates, and volumes, together with the existing C-AGSM’s reactions associated with LSM’s massive developments. This also helps to detect possible local-level socioenvironmental impacts from massive land shape changes, leading to human disasters, including landslides and floods.

DOI： 10.3390/mining2030030

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

The values (i.e., importance) that humans place on ecosystems are critical for sustainable socioecological management. Recently, the value pluralism approach with instrumental, intrinsic, and relational values using multiple disciplines that integrate qualitative and quantitative methodologies has been encouraged. However, these values have received little attention in environmental management. This study explored the values placed on cultural practices among groups experiencing different land cover transformations (LCTs) under the rapid shrinkage of the Limboto Lake, Gorontalo Province, Indonesia, using questionnaires and time-series Landsat and PlanetScope smallsat constellations (SSCs). The time series of LCTs and questionnaire data were computed, visualized, and analyzed statistically using the chi-square test for comparing the two village groups. Results show SSCs enabled a detailed analysis due to high spatiotemporal resolutions in tropical regions. This observation would help in monitoring natural disasters (floods) caused by the decreased lake’s water storing capacity, agricultural damage, locality safety, and environmental protection in shorter cycles. Furthermore, we found that relational values originating from traditional beliefs and practices were the domain values in the land steady-type villages. Hence, integrating the cultural–environmental values of localities with prior spatiotemporal analysis into environmental management policy and implementation processes would be a high-potential alternative for environmental conservation.

DOI： 10.3390/rs14174249

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

The rapid growth of roving mining camps has negatively influenced their surrounding environment. Although artisanal and small-scale gold mining (ASGM) is a major source of gold production, the mining activities and their activeness are not well revealed owing to their informal, illegal, and unregulated characteristics. This study characterizes the transformations of roving camp-type ASGM (R-C-ASGM) activities in Central of Katingan Regency, Central Kalimantan Province, Indonesia, from 2015 to 2021 using remotely sensed data, such as the time-series Sentinel-1 dataset. The results show that the growth of active R-C-ASGM sites was identified at the center of the Galangan mining region with expansions to the northwest part along the Kalanaman River, especially in 2021. Hence, these approaches identify the transformations of roving mining activities and their active or nonactive status even in tropical regions experiencing frequent heavy traffic rainstorms. They provide significant information on the socioenvironmental risks possibly caused at local and regional levels. Our results also inform the design of timely interventions suited to local conditions for strengthening environmental governance.

DOI： 10.3390/ijerph19106266

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Substances found in watersheds and sediments in artisanal and small-scale gold mining (ASGM) areas contaminated by heavy metals are becoming tremendously critical issues in Asia. This study aimed at clarifying the pollution caused by heavy metals in sediments in river basins near ASGM sites in Gorontalo Province, North Sulawesi, Indonesia. Sediment samples collected from experimental areas were classified into nine clay samples and twenty-seven sand samples, whereas three other samples were collected from the control area. Particle-induced X-ray emission was used to analyze these samples. The Statistical Package for the Social Science and the geo-accumulation index (Igeo) were also used for analysis. Based on the results, Hg, Pb, As, and Zn had a concentration of 0–334 µg/g, 5.5–1930 µg/g, 0–18,900 µg/g, and 0–4923.2 µg/g, respectively, which exceeded limits recommended by the U.S. Environmental Protection Agency consensus (1991) and the Indonesian Government Regulation Number 38, 2011. Furthermore, Igeo showed the order of the pollution degree Hg < Zn < Pb < As and reflected an environment contaminated by heavy metals, ranging from unpolluted to extremely polluted areas. Therefore, sediments contaminated by Hg, Pb, As, and Zn could be found along the river basin of mining areas.

DOI： 10.3390/ijerph19106094

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Artisanal and small-scale gold mining (ASGM) is a significant source of gold production globally despite the sector being informal and illegal. The rapid increase in the number of roving mining camps has negatively impacted the surrounding environment; however, the formation and transformation of roving mining camps have not been well studied. This study investigated the long-term trends and significant hotspots of roving camp-type ASGM (R-C-ASGM) in Katingain Regen cy, Central Kalimantan Province, Indonesia, from 1988 to 2020 using remotely sensed data, including Sentinel-1 time-series, global surface water (GSW), and world landcover datasets. Results show that several active R-C-ASGM sites existed in the Galangan and Kalanaman areas in 2017/2018. According to the GSW dataset, the Galangan area was estimated to be formed earlier, whereas the Kalanaman areas were recently formed and were associated with the Kalanaman river expansion. Notably, the center of Galangan was still a significant R-C-ASGM hotspot. The findings of this study broaden our understanding of R-C-ASGM transformation and identify significant R-C-ASGM hotspots over a long period. This study contributes to the development of timely and appropriate interventions for strengthening environmental governance.

DOI： 10.3390/ijerph19095530

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOP Publishing  

Abstract

The leachate containing heavy metals which generated from excavated soil and rock in the civil engineering works appropriate measures are required. We conducted indoor and outdoor experiments to purify heavy metal-containing leachate using a water tank, and proposed a method for treating heavy metals using the purification function of plants at civil engineering works. The plant used was Eleocharis acicularis, which belongs to the Cyperaceae family. The results of the indoor tank experiment on selenium indicated a decrease in the selenium concentration in the leachate from 0.093 to 0.008 mg/L in 14 days. The selenium content per kg of Eleocharis acicularis based on dry weight increased from 0.010 to 0.205 mg, indicating that the plant absorbed selenium. The outdoor tank experiment revealed that the selenium concentration in the leachate decreased from 0.090 to 0.007 mg/L in 21 weeks, and the daily absorption of selenium was 0.0005 mg/L. The lead concentration decreased from 0.004 to 0.001 mg/L in one week, and the arsenic concentration decreased from 0.003 to less than 0.001 mg/L in three weeks. Calculation of the leachate purification cost using Eleocharis acicularis under the current outdoor experiment conditions resulted in a 56% treatment cost reduction compared with the regular treatment cost.

DOI： 10.1088/1755-1315/1027/1/012028

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Other Link： https://iopscience.iop.org/article/10.1088/1755-1315/1027/1/012028/pdf

Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Artisanal and small-scale gold mining (ASGM) has been a major part of people’s livelihood in the rural areas of many developing countries, including those in Southeast Asia (SEA). Nevertheless, because of the use of mercury, ASGM activities have significant local and global adverse impacts on the environment and ASGM community health. Although there have been many monodisciplinary projects by academic researchers and governments to solve the environmental and health problems in SEA ASGM communities, they have not been sufficient to solve the complex socioeconomic problems. This review first outlines the nature of the SEA ASGM activities and the consequent environmental, community health, and socioeconomic problems and then introduces an approach using transdisciplinary communities of practice that involves both academic and nonacademic participants to relieve these wicked ASGM problems and to improve the environmental governance and community health in ASGM communities in SEA.

DOI： 10.3390/ijerph19095422

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Authorship：Lead author   Language：English   Publishing type：Research paper (international conference proceedings)  

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Indonesia is host to a long history of gold mining and is responsible for a significant contribution to world gold production. This is true not only with regard to large gold mining companies but also to small-scale mining groups comprised of people and enterprises that participate in the gold industry of Indonesia. More than two thousand gold mining locations exist in present day Indonesia. Artisanal and small-scale gold mining (ASGM) sites are spread out across thirty provinces in Indonesia, and have provided work opportunities and income for more than two million people. However, the majority of ASGM activities use rudimentary technologies that have serious impacts upon the environment, public health, and miners’ safety, which in turn generate socio-economic impacts for people residing around the mine sites. Moreover, many ASGMs are not licensed and operate illegally, meaning that they are immune to governmental regulation, and do not provide income to the regions and states via taxes. The possibility for more prudent management of ASGM operations could become a reality with the involvement and cooperation of all relevant parties, especially communities, local government, police, and NGOs.

DOI： 10.3390/ijerph19073955

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1080/02604027.2021.2012878

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

In this paper, we report ecological and environmental investigations on Pteris vittata in the As–Pb–Hg-polluted Bone River area, Gorontalo Province, Indonesia. The density distribution of P. vittata decreases from around the artisanal and small-scale gold mining (ASGM) site to the lower reaches of the Bone River, and it is rarely found near Gorontalo City. The maximum concentrations of As, Hg, and Pb recorded in the soil samples were 401, 36, and 159 mg kg−1, respectively, with their maximum concentrations in P. vittata recorded as 17,700, 5.2, and 39 mg kg−1, respectively. Around the ASGM sites, the concentrations of As, Pb, and Hg in P. vittata were highest in the study area. These data suggest that P. vittata, a hyperaccumulator of As, may be useful as a bioindicator for assessing environmental pollution by Pb and Hg.

DOI： 10.3390/ijerph19010530

PubMed

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

This research empirically examines the preferences for job-related attributes among rural villagers living close to artisanal and small-scale gold mining (ASGM) in Indonesia. Based on hypothetical scenarios in which a private company collaborates with the local government to establish a food processing industry in these villages, a questionnaire survey designed with best–worst scaling (BWS) was administered to households to determine their preferences. Additionally, the heterogeneity among the villagers was examined by applying a latent class logit (LCL) model. The main household survey was conducted in 2019 in Bone Bolango Regency, Gorontalo Province. The estimation results revealed that villagers are separated into four classes, and each class has different and unique preferences. Creating more job opportunities for society is a highly evaluated attribute; however, the preference for skill acquisition differs among groups. The results indicate that accounting for heterogeneous preferences regarding job opportunities is helpful to delink dependency on ASGM and health hazards and improve the livelihoods of rural villagers. The study yields key information to substantially reduce environmental and health hazards in the poverty-plagued ASGM community by facilitating job opportunities in Indonesia.

DOI： 10.3390/ijerph19010306

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

It is well known that atmospheric mercury (Hg) contaminates air, water, soil, and living organisms, including trees. Therefore, tree bark can be used for the environmental assessment of atmospheric contamination because it absorbs heavy metals. This study aimed to establish a new biomonitoring for the assessment of atmospheric Hg pollution. Reporting on atmospheric Hg contamination in an artisanal and small-scale gold mining (ASGM) area in North Gorontalo, Indonesia, we calculated the total weight of Hg (THg) and quantitatively measured the concentrations of Hg in the tree bark of Mangifera indica,Syzygium aromaticum, Terminalia catappa, and Lansium domesticum. The THg of Hg in the M. indica tree bark samples ranged from not detected (ND) to 74.6 μg dry weight (DW) per sample. The total Hg in the tree bark of S. aromaticum, T. catappa, and L. domesticum ranged from ND to 156.8, ND to 180, and ND to 63.4 μg DW, respectively. We concluded that topography significantly influences the accumulation of Hg together with local weather conditions. A mapped distribution of the THg suggested that the distribution of THg in the tree bark was not affected by the distance to the amalgamation site. Therefore, tree bark can be used as biomonitoring of atmospheric Hg contamination for the assessment of ASGM areas.

DOI： 10.3390/ijerph19010033

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Authorship：Lead author   Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)   Publisher：国際開発学会  

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Artisanal and small-scale gold mining (ASGM) has a known negative effect on the community’s health; therefore, assessment to monitor community health is essential to detect any issues and enable early treatment. Because ASGM-related health issues are complex and cannot be addressed effectively with a traditional one-time health assessment alone, both long-term and regular health assessments using a transdisciplinary approach should be considered. In response to this need, we designed an online health assessment tool as a reference for a future long-term health assessment system. An online video interview was conducted with 54 respondents living in the ASGM area of Chaung Gyi Village, Thabeikkyin Township, Mandalay Region, Myanmar, via a social networking service application. The tool was used to evaluate community health during the coronavirus 2019 pandemic, including mercury intoxication symptoms, mining-related diseases, and other diseases. Results show that persons working in mining versus non-mining occupations had a greater prevalence of pulmonary diseases, such as pulmonary tuberculosis, silicosis, and bronchial asthma, in addition to malaria. Based on these findings, online health assessment using a transdisciplinary approach can be recommended as an effective tool for sustainable and long-term health assessment of ASGM-related disease and should be performed regularly following physical health surveys.

DOI： 10.3390/ijerph182111206

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

The rapid growth of artificially constructed mining camps has negatively impacted the camps’ surrounding environment and the informal communities that have developed inside the camps. However, artisanal and small-scale gold mining (ASGM) is generally informal, illegal, and unregulated; thus, transformations of the mining activities and potential social-environmental problems resulting from these changes are not revealed. This study assesses the transformation of mining activities in camp-type ASGM sectors in Gorontalo, Indonesia, during 2014–2020 using remotely sensed data, such as Landsat series, nighttime light, and precipitation data obtained through Google Earth Engine. Results show that the combined growth of the built-up areas increased 4.8-fold, and their annual mean nighttime light increased 3.8-fold during 2014–2019. Furthermore, diverse increases in the sizes of area and nighttime light intensity were identified from the mining camps. Among the studied camps, since 2017, Motomboto camp 3 showed a particularly rapid change in activity regardless of the season of the year. Hence, these approaches are capable of identifying rapid transformations in the mining activities and provide significant insight into the socio-environmental problems originating from the closed and vulnerable camp-based ASGM sector. Our results also contribute to developing rapid and appropriate interventions and strengthening environmental governance.

DOI： 10.3390/ijerph182010954

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Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Mining sites development have had a significant impact on local socioeconomic conditions, the environment, and sustainability. However, the transformation of camp-type artisanal and small-scale gold mining (ASGM) sites with large influxes of miners from different regions has not been properly evaluated, owing to the closed nature of the ASGM sector. Here, we use remote sensing imagery and field investigations to assess ASGM sites with large influxes of miners living in mining camps in Bone Bolango Regency, Gorontalo Province, Indonesia, in 1995–2020. Built-up areas were identified as indicators of transformation of camp-type ASGM sites, using the Normalized Difference Vegetation Index, from the time series of images obtained using Google Earth Engine, then correlated with the prevalent gold market price. An 18.6-fold increase in built-up areas in mining camps was observed in 2020 compared with 1995, which correlated with increases in local gold prices. Field investigations showed that miner influx also increased after increases in gold prices. These findings extend our understanding of the rate and scale of development in the closed ASGM sector and the driving factors behind these changes. Our results provide significant insight into the potential rates and levels of socio-environmental pollution at local and community levels.

DOI： 10.3390/ijerph18189441

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Revista de Chimie SRL  

This study demonstrates the potential use of volcanic ash soil (VAS) as raw materials for preparing zeolite without adding any templates or seeds. Here we investigated the effect of alkaline concentrations on the synthesis of VAS-based zeolite and enhanced its ability for methylene blue (MB) removal by Fenton-like process. Zeolite materials were directly synthesized by mixing the amount of VAS within alkaline concentrations of 0.5 (P1), 1.5 (P2), and 3.0 mol/L (P3), respectively, followed by a simple hydrothermal procedure at 100 oC for 24 h. The prepared sample characteristics were obtained from the Fourier transform infrared (FTIR) and X-ray diffraction (XRD) analysis, which confirmed the formation of zeolite A and some mineral phases in P2 and P3 samples. The mentioned samples reached equilibrium state at MB concentration of 200 mg/L with high adsorption capacity values compared to VAS. The adsorption showed a better fit to the Langmuir isotherm model (R2]0.99), in which the maximum uptake capacities were found to be 24.03 mg/g for P2 and 14.30 mg/g for P3. Interestingly, the percentage of MB removal using P2 and P3 increased greatly from 52.81% and 32.26% to 98.92% and 98.85% by Fenton-like process, respectively.

DOI： 10.37358/rc.20.12.8385

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Taylar＆Francis  

DOI： 10.1080/02772248.2020.1839074

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IOP Publishing  

DOI： 10.1088/1755-1315/589/1/012013

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Other Link： https://iopscience.iop.org/article/10.1088/1755-1315/589/1/012013

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IOP Publishing  

DOI： 10.1088/1755-1315/589/1/012019

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Other Link： https://iopscience.iop.org/article/10.1088/1755-1315/589/1/012019

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IOP Publishing  

DOI： 10.1088/1755-1315/589/1/012015

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Other Link： https://iopscience.iop.org/article/10.1088/1755-1315/589/1/012015

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IOP Publishing  

DOI： 10.1088/1755-1315/589/1/012020

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Other Link： https://iopscience.iop.org/article/10.1088/1755-1315/589/1/012020

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IOP Publishing  

DOI： 10.1088/1755-1315/589/1/012007

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Other Link： https://iopscience.iop.org/article/10.1088/1755-1315/589/1/012007

Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

This study explores the mechanisms behind the rapid shrinkage of Limboto Lake, Gorontalo, Indonesia, using remotely sensed imagery and river outcrop investigation data. The results show that more than 70% of the sedimentation resulting in shrinkage is contributed by riverbank erosion causing rivers to drain into the lake during the period 2003–2017. From geological investigation, it is found that the lowland area to the west of Limboto Lake comprises 1 m of flood sediments, followed by at least 5 m of fine-grained inner bay sediments. Severe riverbank erosion is also observed at many points. Hence, it is concluded that the shrinkage of Limboto Lake resulted from rapid-induced rapid erosion of inner bay sediments formed during plate collision which readily flowed into and were deposited in Limboto Lake; this created a delta, especially on the west side of the lake. Accelerated sedimentation caused by river erosion has led to rapid lake shrinkage. This phenomenon could be typical of the transformation of enclosed seas into lakes by the rapid uplifting movement of land in collision zones.

DOI： 10.3390/su12229598

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Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Increasing artisanal and small-scale gold mining (ASGM) in developing countries has raised health concerns in mining communities. A preliminary health survey was conducted in Thabeikkyin Township, Mandalay Region, Myanmar, in February 2020 to assess the health conditions of an ASGM community. Respiratory function and other clinical assessments were evaluated in miners and non-miners, and participants’ hair was analyzed for heavy metals. Respiratory function of miners was similar to that of non-miners. However, miners’ respiratory function declined with longer mining activity duration. In total, 3 out of 18 miners showed neurological signs and symptoms of chronic mercury intoxication. The median concentration of the hair mercury was significantly higher in miners than non-miners (P = 0.01), and 9 out of 18 miners and 2 out of 11 non-miners showed the warning level of mercury. We found that, despite an association between declining respiratory function and length of time mining, only a minority of miners showed clinical features of chronic mercury intoxication. Further clinical surveys with a larger sample size are necessary to determine the broader health status of this community. In addition, clinical indicators such as pulmonary function tests are recommended as additional criteria for the diagnosis of mercury intoxication.

DOI： 10.3390/ijerph17186757

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Despite legal and safety issues, skin-lightening cosmetic products—including hazardous mercury-containing cosmetics—are in increasing demand in Indonesia. Perceptions of beauty may result in desires to have lighter skin tones, regardless of the safety of these cosmetics, which block the production of melanin and thus lighten skin tone. This study investigated Hg exposure of students using skin-lightening cosmetics and assessed the health issues. A total of 105 female students were given a questionnaire regarding their use of cosmetics; a further 43 students formed a non-cosmetic-user control group. Their scalp hair and cosmetic products were analyzed by particle-induced X-ray emission (PIXE) spectroscopy. The geometric-mean hair Hg concentration for the cosmetics-using students was 6.7 µg g−1—three times that of the control group (2.3 µg g−1). Of twenty-seven cosmetic samples were analyzed, twenty had Hg concentrations of 0.12–7834.4 µg g−1 (mean 554.6 µg g−1), and seven had no detectable Hg. The hair Hg concentrations exhibited a statistically significant correlation with cosmetic Hg concentration. The health assessments indicated only rigidity & ataxia and irregular eye movement were prevalent in the cosmetic-using students with less than 7% occurrences.

DOI： 10.3390/cosmetics7030058

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IOP Publishing  

© Published under licence by IOP Publishing Ltd. The extraordinary of geodiversity together with the ecological resources and profound cultural heritages provide a valuable basic of geotourism and geopark development. The purpose of this paper is to show the possibilities of geological interpretation, geotourism, and cultural heritages in the area of Gorontalo province that would become valuable basic to promote geopark. The collected data was carried out by field observation and literature review. The results of this study indicate that the Gorontalo has the potential of geopark and would serve as tourist destination in Sulawesi by applying the concept of Geotourism which accentuate natural side, by optimizing the management of destination attractions, facilities and services, and accessibilities.

DOI： 10.1088/1755-1315/536/1/012004

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Other Link： https://iopscience.iop.org/article/10.1088/1755-1315/536/1/012004

Publishing type：Research paper (international conference proceedings)   Publisher：IOP Publishing  

DOI： 10.1088/1755-1315/536/1/012003

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Other Link： https://iopscience.iop.org/article/10.1088/1755-1315/536/1/012003

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IOP Publishing  

DOI： 10.1088/1755-1315/536/1/012009

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Other Link： https://iopscience.iop.org/article/10.1088/1755-1315/536/1/012009

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IOP Publishing  

DOI： 10.1088/1755-1315/536/1/012007

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Other Link： https://iopscience.iop.org/article/10.1088/1755-1315/536/1/012007

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IOP Publishing  

DOI： 10.1088/1755-1315/536/1/012008

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Other Link： https://iopscience.iop.org/article/10.1088/1755-1315/536/1/012008

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：IOP Publishing  

DOI： 10.1088/1755-1315/536/1/012005

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Other Link： https://iopscience.iop.org/article/10.1088/1755-1315/536/1/012005

Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOP Publishing  

DOI： 10.1088/1755-1315/536/1/012006

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Other Link： https://iopscience.iop.org/article/10.1088/1755-1315/536/1/012006

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3390/toxics8010015

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Silicon (Si) has been recently reconsidered as a beneficial element due to its direct roles in stimulating the growth of many plant species and alleviating metal toxicity. This study aimed at validating the potential of an aquatic macrophyte Eleocharis acicularis for simultaneous removal of heavy metals from aqueous solutions under different dissolved Si. The laboratory experiments designed for determining the removal efficiencies of heavy metals were conducted in the absence or presence of Si on a time scale up to 21 days. Eleocharis acicularis was transplanted into the solutions containing 0.5 mg L−1 of indium (In), gallium (Ga), silver (Ag), thallium (Tl), copper (Cu), zinc (Zn), cadmium (Cd), and lead (Pb) with various Si concentrations from 0 to 4.0 mg L−1. The results revealed that the increase of dissolved Si concentrations enhanced removal efficiencies of E. acicularis for Ga, Cu, Zn, Cd, and Pb, while this increase did not show a clear effect for In, Tl, and Ag. Our study presented a notable example of combining E. acicularis with dissolved Si for more efficient removals of Cu, Zn, Cd, Pb, and Ga from aqueous solutions. The findings are applicable to develop phytoremediation or phytomining strategy for contaminated environment.

DOI： 10.3390/w11050940

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3390/ijerph15112480

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Multidisciplinary Digital Publishing Institute  

DOI： 10.3390/w10111507

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

We report the atmospheric Hg contamination in an artisanal and small-scale gold mining (ASGM) area in North Gorontalo, Indonesia. It is well known that atmospheric Hg contaminates the air, water, soil, and living organisms, including trees. In this study, we calculated total weight of heavy metals, especially Hg, and quantitatively measure the concentrations of heavy metals, especially Hg, in tree bark from an ASGMarea. Tree bark can be used for the environmental assessment of atmospheric contamination because it attaches and absorbs heavy metals. Atmospheric Hg and other heavy metals, including Fe and Mn, and As were detected on the tree bark samples. The total weight of Hg, As, Fe, andMn in the tree bark samples ranged fromundetectable (ND) to 9.77,NDto 81.3, 124-4028, 37.0-1376 _g dry weight (DW), respectively per weight of sample. Based on quantitatively analysis micro-PIXE, the highest concentrations of all thesemetals were detected in the outer part of the bark. We conclude that tree bark can adsorb atmospheric contamination, which is then absorbed into the inner tissues.

DOI： 10.3390/geosciences8010031

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

The industrial mining sector is one of the main contributors to environmental damage and toxic metal pollution, although some contamination originates from natural geological sources. Due to their position at the top of the food chain, cattle tend to bioaccumulate mercury (Hg) in their bodies. We used analyses of cattle hair samples to investigate Hg contamination in cattle farmed within and outside of an artisanal and small-scale gold-mining area in Bombana, Southeast Sulawesi, Indonesia. We also examined the factors that might have influenced the toxicity, such as the environmental conditions, sex, and age of the cattle. A total of 63 hair samples were analyzed by particle-induced X-ray emission spectrometry. The mean Hg concentration was significantly higher in hair from cattle farmed within the artisanal and small-scale gold mining area (11.44 µg/g hair) than in those farmed outside the area (2.89 µg/g hair, p &lt
0.05). A possible cause of this is contamination by mercury persistent in terrestrial food chain. The results indicates that the level of toxic metals such as Hg need to be controlled in food sources to protect human health, especially in Bombana, Indonesia.

DOI： 10.3390/geosciences7040133

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Language：English  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Urban artisanal gold mining (UAGM) in Makassar, South Sulawesi, Indonesia, has been run by a number of urban gold workers with gold jewelry manufacture as its core activity. The wastes generated from goldsmiths’ activities were further processed by the gold smelters to recover fine gold particles. Smelting gold doré, amalgamation, and burning out the amalgam were the mercury-based gold process usually applied in their work. While working the gold workers are, therefore, potentially exposed to a source of mercury pollution that may cause health problems because of working without proper protection. The aims of this research are to characterize the process of urban artisanal gold mining with the potential mercury exposures during the process, and to assess the health of the gold workers. The results showed that the gold workers had a low educational background, but a relatively high income. The total mercury concentration of gold workers was higher than the control group. They were exposed to intoxicatingly high levels of mercury with the average total mercury concentrations of 6.6 and 10.8 _g/g in the hair of indirect and direct exposed workers, respectively. The health assessment showed that 85% of the gold workers suffered neurological symptoms, such as tremors, and 44%–56% of them experienced restricted fields of vision, slow reflexes, sensory disturbances, unbalanced rigidity, and ataxia. The results also showed that the working years have reasonable correlation with the sum of the positive findings in the 10 neurological symptoms.

DOI： 10.3390/geosciences7030044

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Language：Japanese   Publishing type：Research paper (scientific journal)  

File： インドネシア国ゴロンタロ州における「海外フィールドワーク実習」パイロットプログラムの実施報告.pdf

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Institute of Physics Publishing  

Many petrological studies of volcanic rocks have attempted to better predict future volcanic activity. In this study, we examined volcanic ash samples from Showa Crater in Sakurajima, Japan, which were erupted from January to October 2013. This study was used two types of juvenile material
black vesicular volcanic rock (BVVR) and black non-vesicular volcanic rock (BNVVR) to determine the variable of magmatic processes in the magma conduit during the 2013 eruption. We divided the duration into three periods such as January to April, April to July, and July to October based on the variable tendency of SiO2 contents and volume abundance of the interstitial glasses in BVVR and BNVVR. The estimated melt compositions demonstrate that the variability of SiO2 contents and volume abundance of microcrystal in the groundmass (BVVR and BNVVR) over time were caused by micro-crystallization processes. The estimated of water contents and vesicle volume shows the influence of degassing process in the rock forming. Also, the correlation of petrological features with the number of eruptions and eruptive volumes, exhibit the variable of magma supply into conduit in each period. Consequently, careful monitoring of the petrological features of erupted materials may provide useful constraints on future eruptive activity and thereby assist in the mitigation of volcanic hazards.

DOI： 10.1088/1755-1315/71/1/012008

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Institute of Physics Publishing  

Phytoremediation using aquatic plants is a sustainable, low-cost measure for remediating water contaminated by toxic heavy metals. In this study, we conducted a channel experiment using Eleocharis acicularis in heavy metal-contaminated mildly alkaline wastewater under unfavorable plant habitat conditions in winter in northeastern Japan. The wastewater from an embankment consisting of Neogene marine sediments had a temperature of 10-15 °C and a pH of about 9, and it contained ∼0.02 mg/L of As and ∼ 0.23 mg/L of Mo. About 16 kg (fresh weight) of E. acicularis was laid in a plastic channel measuring 30 cm in width by 20 m in length, and the channel was enclosed in a tunnel greenhouse. The experiment was conducted for the 3 months from November 2015 at an average flow rate of 0.3 L/min and an air temperature of -4 to 19 °C. No reductions in As or Mo concentrations in the outflow were detected. However, at 3 months, the E. acicularis showed accumulations of ∼7 mg/kg As and ∼18 mg/kg Mo as dry weight, indicating that this remediation method is workable in an unfavorable low-temperature, mildly alkaline environment.

DOI： 10.1088/1755-1315/71/1/012018

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Institute of Physics Publishing  

Kapok (Ceiba pentandra, family Bombacaceae) fiber (KF) is a by-product of traditional agriculture in tropical countries and is mainly used as fiberfill in fabric. The aim of this study was to explore the possibility of using KF to remove clay particles from turbid water. Firstly, KF was boiled at 100 °C in deionized water for 15 min to remove the surface oil. A suspension of montmorillonite powder mixed 1 L of deionized water, divided into volumes of 100, 200, 300, and 400 mL, was used as the turbid water source. The ability of KF to remove clay particles from the water was assessed by filtering the water through 60 g of treated KF in a ∼397.9 cm3 acrylic column. Results showed that the treated KF effectively removed the clay particles from the entire volume of turbid water in this experiment
the results also demonstrate that this KF fiber has value as a simple and inexpensive tool for water treatment, especially in developing countries.

DOI： 10.1088/1755-1315/71/1/012017

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Institute of Physics Publishing  

The traditional gold smelting in Makassar, South Sulawesi, Indonesia, is an informal work with the manufacture of gold jewelry as the core activity. Stages of the gold processing include panning, smelting, and refining with mercury. In the current study, we used a social demography analysis to classify the traditional gold smelter workers in this region. Data (e.g. sex, age, education level, time working, and income) were obtained from a questionnaire survey of 58 smelter workers in the Wajo and Tallo Sub-districts of Makassar. Results showed that 84.5% of the workers were males aged from 21 to 50 years with on the average 15 year of work. The gold smelter were last educated in elementary school (31.0%), junior high school (36.2%), and senior high school (27.6%) levels whereas 5.1% have no education. We found that the monthly income of an un-skilled worker was ∼Rp. 2 million (USD 147.0) whereas that of a skilled worker was between Rp. 2.5 million (USD 183.76) and Rp. 5 million (USD 367.51). An owner could earn over Rp. 5 million (USD 367.51) per month. The result suggested that the traditional gold smelting used rudimentary technique and attracted young people with a low education level. This business continues to exist because the worker earn sufficient income and may higher through mastering gold smelter proficiency.

DOI： 10.1088/1755-1315/71/1/012027

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Institute of Physics Publishing  

There is a consensus that the artisanal small-scale gold mining (ASGM) sector contributes to trapping individuals in a cycle of poverty and financial insecurity with a low standard of living. The purpose of this study was to analyze the economic circumstances of miners in the Bombana ASGM area in Indonesia using a mixed methodology approach that involved collecting, analyzing, and mixing both quantitative and qualitative data in a single study. Results show that the average and maximum monthly incomes of 201 miner households were Rp. 4,360,000 and Rp. 9,750,000, respectively. The average income in the ASGM area in Bombana was higher than that at similar sites on Java Island (∼Rp. 2,900,000) and was much higher than the average monthly income of the inhabitants of Bombana (∼Rp. 2,100,000). Because of the higher revenue generated in the ASGM sector, miners and their families depend long-term on the mining work, which makes it difficult to control the mining activity and the associated environmental degradation.

DOI： 10.1088/1755-1315/71/1/012016

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Institute of Physics Publishing  

As a solution to economic poverty, we investigated the possibility of developing pearl farming in Kabupaten Gorontalo Utara region of Indonesia. The approximate income of farmers is 15 - 28 million rupiah/year, and that of fishers is 51 million rupiah/year. As these incomes are low and unreliable, it is important that food processing and other industries are developed and that agriculture and fisheries are promoted. Pearl farming minimize environmental load. The coastal environmental conditions are good for pearl shell growth. From 2001 till 2013, pearl farming was undertaken by a Japanese company in Kabupaten Gorontalo Utara, but the operation caused because of conflict with local people and issues with the actions of manager. To establish successful pearl farming businesses it is more important to address social issues than environmental factors.

DOI： 10.1088/1755-1315/71/1/012019

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Institute of Physics Publishing  

Mine dumps pose environmental problems worldwide. Phytoremediation is a remediation technique that uses plants to clean polluted environments. Athyrium yokoscence, a fern of the family Aspidiaceae, is a well-known Cd hyperaccumulator used in phytoremediation. The aim of the current study is to determine the extent of heavy metal absorption by A. yokoscence and evaluate its potential use in phytoremediation. The shoots, stems, and roots of A. yokoscence were analysed by inductively coupled plasma-optical emission spectrometry (ICP-OES) to determine the concentrations of Cd, As, Pb, Cu, and Zn, yielding maximum concentrations in the shoots of 851, 215, 192, 60.9, and 769 mg/kg-DW, in the stems of 481, 140, 881, 28.9, and 495 mg/kg-DW, and in the roots of 1210, 1868, 6473, 2484, and 5446 mg/kg-DW, respectively. The results indicate that A. yokoscence is a hyperaccumulator of Cd and can be used for the translocation of As, Pb, Cu, and Zn within the shoot tissue. The roots translocate heavy metals through the stems and they finally reside within the shoot tissue. The results suggest that A. yokoscence has considerable potential use as an environmental assessment tool for Cd, As, Pb, Cu, and Zn, and in helping to remediate mine dumps.

DOI： 10.1088/1755-1315/71/1/012025

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Institute of Physics Publishing  

We performed the Particle Induced X-ray Emission (PIXE) analysis on scalp hair samples of 115 ASGM miners and inhabitants of Gorontalo Utara regency. Along with mercury (Hg), we presented other trace elements such as Copper (Cu) and Manganese (Mn). Concentrations of Cu, Mn and Hg in the scalp hairs of ASGM miners are higher non miners. Significant and positive correlations coefficients between Cu and Hg concentration with Mn concentration may indicate that there are still unknown metabolism process related with ASGM activities.

DOI： 10.1088/1755-1315/71/1/012028

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DOI： 10.3390/environments4020040

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Language：English   Publisher：Springer  

DOI： 10.1007/s40831-017-0130-8

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Language：Japanese  

File： 人工水路を用いた植物によるヒ素を含む水の浄化技術2017.pdf

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

The rapid expansion of the artisanal and small-scale gold mining (ASGM) industry in developing countries has marginalized the local communities in poverty, and resulted in occupational exposure to mercury via the gold extraction process. We investigated the mercury exposure of the mining workers lived inside and outside the mining area. Based on the occupations of the contributors, the hair samples were divided into three subgroups: directly exposed, indirectly exposed, and a control. A total of 81 hair samples were analyzed by particle-induced X-ray emission spectrometry. The median mercury concentration was highest in the hair from the directly exposed group (12.82 μg/g hair) (control group median: 4.8 μg/g hair, p &lt
0.05), and the concentrations in hair from 45 respondents exceeded the Human Biomonitoring I (HBM I) threshold limit. Mercury concentrations were also elevated in the hair from the indirectly exposed group (median 7.64 μg/g hair, p &lt
0.05), and concentrations in hair from 24 respondents exceeded the HBM I threshold limits. Exposure to mercury during ASGM presents health risks and is harmful for the miners
mercury is also at hazardous levels for people who live in the mining area but who are not engaged in mercury-based gold extraction.

DOI： 10.3390/toxics5010007

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Language：English   Publisher：Trade Science  

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File： 「課題解決思考力を育む海外準正課プログラム」構築に向けた実践報告]2017.pdf

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Authorship：Lead author  

File： P25-P32 インドネシア国ゴロンタロ州における「海外インターンシップ実習」パイロットプログラムの実施報告.pdf

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Language：English  

DOI： 10.3390/environments3040035

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Authorship：Last author   Language：Japanese   Publishing type：Research paper (scientific journal)  

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Publishing type：Research paper (international conference proceedings)  

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Language：English  

DOI： 10.3390/environments3030015

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File： NMCC共同利用研究成果報文集22（2015）岡田弘.pdf

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Sakurajima in Japan is one of the world’s most active volcanoes. This paper presents the results of a petrological study of the Showa Crater volcanic ash samples ejected from January 2011 to November 2012 from Sakurajima. The aim of this paper is to reconstruct the evolution in time of the conduit magma system, based on the compositions and physical properties of the studied volcanic ash. We analyzed the composition of interstitial glass and microcrystal of Black Volcanic Rock (BVR) and Black Vesicular Volcanic Rock (BVVR) in order to estimate the magma ascent rate. The results show that SiO2 content of interstitial glass and crystallinity of the BVR is generally higher than for BVVR. The different types of juvenile material likely resulted from cooling-induced crystallization and decompression-induced crystallization in the conduit. The conditions of magma transit within the conduit from 2011 to 2012 differ: in 2011, the decompression rate and magma ascent rate of BVR were higher than for BVVR, but, in 2012, the decompression rate and magma ascent rate between BVR and BVVR were similar. As such, monitoring the petrological features of dated eruptive materials could provide useful information for evaluating ongoing eruptive activity.

DOI： 10.3390/geosciences6010012

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Geological Agency  

The development in modern-high technology application is growing rapidly, resulting in the constant supply of critical metal and rare earth elements (REE). Currently, resources of these elements are restricted and new source of these elements need to be discovered accordingly. Scandium (Sc) as one of critical metals is an important metal for electrolyte of solid oxide fuel cells and other advance technology. In addition, REE are the important elements in the use of permanent magnets and rechargeable batteries. This manuscript reports an overview on the possibility of scandium and rare earth element occurrences in Sulawesi. Sc is concentrated in limonite layers in Soroako ultramafic rocks as a result of Fe3+ site substitution of mafic minerals (pyroxene, amphibole, etc.) during a laterization process. REE are enriched in association with clay minerals in B horizon from heavily weathered granitic rocks in Palu and Masamba, suggesting the possibility of ion-adsorption style mineralization. The lateritic soil of the ultramafic rocks and the weathered crusts of the granitic rocks in Sulawesi could be the potential sources of scandium and rare earth elements, respectively.

DOI： 10.17014/ijog.3.2.139-147

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：AMER INST PHYSICS  

Environmental contamination is one of the most important factors responsible for degradation of the surface environment on the earth. Heavy metals play a dominant role in this degradation. Phytoremediation is an environmental remediation technique that takes advantage of plant physiology and metabolism. The purpose of this paper is to review the previous papers on the phytoremediation experiments of Eleocharis acicularis. The E. acicularis is easily cultivated and controlled in environments with abundant water, hyperaccumulates Cu, Zn, As, Pb, Cd, Cs and Hg; showing great potential for use in the phytoremediation of water environments contaminated by the heavy metals. The E. acicularis shows great potential for use in the phytoremediation of water environments contaminated by heavy metals including radiogenic elements. The present results also indicate that phytoremediation by the E. acicularis is likely to be widely applicable to tropical areas of Southeast Asia.

DOI： 10.1063/1.4953512

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Language：Japanese  

CiNii Books

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Language：English   Publisher：Japan Association for Quaternary Research  

The Shoubu volcanic ash is intercalated with the middle Pleistocene Iyoki Formation, western Shikoku, Japan. The ash has been petrographically correlated with several widespread tephras, but detailed geochemical correlations have yet to be made. We therefore examine the lithology, petrography, glass geochemistry, and fission-track (FT) ages of the Shoubu ash in an attempt to establish robust, detailed correlations. The petrography and chemical composition of glass show vertical trends in the Shoubu ash. The FT age of the lowest unit indicates that eruptions began at 0.53±0.12Ma. Although the Shoubu ash has previously been interpreted as a single, homogeneous volcanic ash, the results indicate that it either comprises several volcanic ashes or records a compositional change within a single eruptive sequence.

DOI： 10.4116/jaqua.54.359

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Other Link： https://jlc.jst.go.jp/DN/JLC/20018999646?from=CiNii

Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

The lichen, Stereocaulon exutum Nylander, occurring in a contaminated abandoned mine site was investigated to clarify (1) the behavior of heavy metals and As during the slag weathering processes mediated by the lichen; and (2) the distribution of these elements in the lichen thallus on slag. The heavy metals and As in the slag are dissolved from their original phases during the weathering process by lichen substances (organic acids) and hypha penetration, in addition to non-biological weathering. The dissolved elements are absorbed into the lichen thallus. Some of these dissolved elements are distributed in the cells of the hyphae. The others are distributed on the surface of the hyphae as formless particles and show lateral distribution inside the cortex of the thallus. The Cu and Zn concentrations in the thalli are positively correlated with the concentrations in the corresponding substrata and a positive intercept in the regression curve obtained using a linear function. These chemical characteristics make this lichen a good biomarker for Cu and Zn contamination of the substrata of the lichen. Therefore, the present study supposes that Stereocaulonexutum has a possible practical application in biomonitoring or risk assessment of heavy metal pollution at abandoned mine sites.

DOI： 10.3390/met5031591

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Language：Japanese  

J-GLOBAL

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Mercury concentrations in the environment (river sediments and fish) and in the hair of artisanal gold miners and inhabitants of the Gorontalo Utara Regency were determined in order to understand the status of contamination, sources and their impacts on human health. Mercury concentrations in the sediments along the Wubudu and Anggrek rivers are already above the tolerable level declared safe by the World Health Organization (WHO). Meanwhile, commonly consumed fish, such as snapper, have mercury levels above the threshold limit (0.5 μg/g). The mean mercury concentrations in the hair of a group of inhabitants from Anggrek and Sumalata are higher than those in hair from control group (the inhabitants of Monano, Tolinggula and Kwandang). The mean mercury concentration in the hair of female inhabitants is higher than that in the hair of male inhabitants in each group. Neurological examinations were performed on 44 participants of artisanal and small-scale gold mining (ASGM) miners and inhabitants of Anggrek and Sumalata. From the 12 investigated symptoms, four common symptoms were already observed among the participants, namely, bluish gums, Babinski reflex, labial reflex and tremor.

DOI： 10.3390/geosciences5020160

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Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：KNOWLEDGE E  

Soil in the Fukushima area has been polluted with the radioactive contaminants such as Cs by the accident of Fukushima Daiichi nuclear power plant in March 2011. Remediation of soil contaminated with radioactive Cs remains one of the most important problems. Phytoremediation is an environmental remediation technique that takes advantage of plant physiology and metabolism to remove radioactive contaminants. Eleocharis acicularis is well known as heavy metal hyperaccumulator aquatic plant and expected as the strong candidate for application to Phytoremediation of polluted water and soil. In this study, a laboratory experiment was carried out to investigate the potential of E. acicularis for Phytoremediation of radioactive Cs contaminated site. The plants were grown hydroponically and placed in solutions containing Cs and K at different concentration (Cs concentration: 5 mg/L, K concentration: 0, 0.2, 2, 5, 50, 100 mg/L) in a period of 21days. In the experimental results, the highest concentration of Cs was 1560 mg/kg-DW in E. acicularis after 21 days. The concentration of Cs in plants decreased with the increasing initial concentration of K in the solution. This results indicate that E. acicularis has the ability to accumulate radioactive Cs from radioactive Cs contaminated soil and water, making it a good candidate species for radioactive Cs Phytoremediation.

DOI： 10.18502/kls.v2i1.209

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Language：Japanese  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OPTICAL SOC AMER  

Red fluorescence lamellae in prismatic layers of Pinctada vulgaris shell were investigated. SEM-EDS, XRD, and TG-DTA were utilized to characterize prismatic layers. We found that prismatic layers are calcitic prismatic (CP) layers with rich organic substances. Excitation spectrum for red fluorescence determined by a spectrophotometer indicates that the fluorescent matter in the organic substances is porphyrin compound derivatives. By using a fluorescence microspectroscope, the cross section of CP layers shows red fluorescence forming lamellar pattern. The lamellar pattern consists of red and black parallel zones with a modulation of emission intensity. Elemental mapping show a correlation of the fluorescence intensity decay with sulphur-rich zones occupying the CP layers in the black zones. (C)2014 Optical Society of America

DOI： 10.1364/OME.4.001813

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The past two decades have seen the reporting of microbial fossils within ancient oceanic basalts that could be identical to microbes within modern basalts. Here, we present new petrographic, mineralogical, and stable isotopic data for metabasalts containing filamentous structures in a Jurassic accretionary complex within the northern Chichibu Belt of the Yanadani area of central Shikoku, Japan. Mineralized filaments within these rocks are present in interstitial domains filled with calcite, pumpellyite, or quartz, and consist of iron oxide, phengite, and pumpellyite. delta C-13(PDB) values for filament-bearing calcite within these metabasalts vary from -2.49 parts per thousand to 0.67 parts per thousand. A biogenic origin for these filamentous structures is indicated by (1) the geological context of the Yanadani metabasalt, (2) the morphology of the filaments, (3) the carbon isotope composition of carbonates that host the filaments, and (4) the timing of formation of these filaments relative to the timing of low-grade metamorphism in a subduction zone. The putative microorganisms that formed these filaments thrived between eruption (Late Paleozoic) and accretion (Early Jurassic) of the basalt. The data presented here indicate that cryptoendolithic life was present within water-filled vesicles in pre-Jurassic intraplate basalts. The mineralogy of the filaments reflects the low-grade metamorphic recrystallization of authigenic microbial clays similar to those formed by the encrustation of prokaryotes in modern iron-rich environments. These findings suggest that a previously unusual niche for life is present within intraplate volcanic rocks in accretionary complexes. (C) 2013 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.pss.2013.05.008

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Microbial trace fossils on terrestrial basalts can be used as an analogue in the search for traces of life on other terrestrial planets. This study reports on microbial trace fossils within Permian greenstones in the Maizuru Terrane, southwest Japan, which is recognized as back-arc basin oceanic crust that consists mainly of metabasalt and metagabbro. The trace fossils have been studied by means of morphology, mineralogy, elemental mapping, and carbon isotope analysis. Although minute original textures of trace fossils are recrystallized in these rocks, Granulohyalichnus vulgaris isp., Tubulohyalichnus spiralis isp., and Tubulohyalichnus annularis isp. were identified. Significant concentration of C within the trace fossils implies these are organic remnants from microbes. The delta C-13(PDB) values < -7 parts per thousand of calcite within the greenstones indicates that the bacterial activity took place prior to the formation of calcite veins. The results support that microbial trace fossils within low-grade metamorphic basalt can be reliably identified based on their morphology and chemical composition, as reveled by elemental mapping. In this context, glassy Martian basalt may be the best rock type to investigate in terms of searching for signs of microbial activity on Earth and other planets. (C) 2013 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.pss.2013.09.018

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Understanding the primary relationships between basaltic rocks and fossiliferous sedimentary rocks provides direct information on the timing and geologic setting of past oceanic igneous activity. Though the basalts associate with cherts in the Northern Chichibu Belt have been petrographically identified as OIA/OIT or MORB, such primary relationships of them are not well understood.
This paper provides the primary intrusive relation of basaltic rocks contact with chert and calcareous siliceous shale of Sugyo area in the Northern Chichibu Belt on Shikoku Island. The sediments are included within the basalt as xenoliths and in the contact zone with the basalt they have been recrystallized and contain metamorphic minerals possibly produced by contact metamorphism due to the basalt intrusion. These indicate that the basalts are sills or dykes that have intruded the sediments. The cherts are radiolarian chert which alternate with the calcareous siliceous shale and include minerals of oceanic volcanic origins. Asselian radiolarian fossils are yielded from a subangular chert xenolith that was intruded by the basalt possibly before the chert had undergone complete diagenesis. The petrography of the sills indicates they are alkali basalts. X-ray fluorescence analyses indicate that the basaltic rocks include subalkaline basalts and oceanic island tholeiite or oceanic island alkaline basalts.
We have concluded that the basaltic dykes and sills were products of Asselian or younger intra-plate volcanism at an oceanic area covered by a pile of pelagic siliceous sediments. These Asselian cherts are earlier than the Sakmarian, Wordian and Capitanian limestones that overlie intra-plate basalts of Ohnogahara part of the Northern Chichibu Belt. The basalt sills may therefore represent the early stages of intra-plate igneous activity in the paleo-Pacific Ocean. (C) 2013 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jseaes.2013.09.016

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Publisher：The Geological Society of Japan  

DOI： 10.14863/geosocabst.2014.0_535

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

Artisanal metallurgical slag produced more than 50 years ago at a mine site in southwest Japan is rich in toxic metals and metalloids. Some of the slag remains on a waste dump and could contaminate the surrounding area through the dissolution of heavy metals and metalloids during weathering. To assess this risk, this study has investigated the behavior of the toxic elements in the smelting slag during weathering. Most of the potentially toxic elements are contained in willemite and/or matte drops. Maximum metal and metalloid concentrations in the slag are 28.1 wt % Fe, 22.7 wt % Zn, 1.63 wt % Cu, 3450 mg/kg Sn, 826 mg/kg Pb, 780 mg/kg As, and 116 mg/kg Cd. Zn is mainly contained in willemite, whereas other metals and metalloids are mainly concentrated in matte drops. The willemite and matte drops are converted to Fe-hydroxides during weathering, indicating that potentially toxic metals and metalloids contained in these phases are released by weathering processes. Therefore, weathering of the artisanal metallurgical slag, containing large amounts of willemite and matte drops, may pollute the surrounding environment.

DOI： 10.3390/min3040412

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

Pyrite framboid in sedimentary rocks could be concerned with arsenic contamination in groundwater of acidic environment and has been studied for the formation process of its unique morphology. However, not much has been discussed about the formation process based on the heavy-metal distribution in pyrite framboids and their aggregates. To reveal the formation process of pyrite framboids and their aggregates, mudstone from the Late Cretaceous Hakobuchi Group, central Hokkaido, Japan, are investigated for mode, petrographical, mineralogical, and micro-PIXE (particle-induced X-ray emission) analysis in this study. Spherical and sub-spherical pyrite framboids observed in polyframboids can be divided into two types based on the diameter of framboids (D) and the average diameter of microcrystals (d) within framboids: type 1, ranging from 2 to 9 mu m and from 0.4 to 0.9 mu m, respectively, and type 2, ranging from 8 to 50 mu m and from 0.5 to 1.8 mu m, respectively. Based on the quantitative traverse analyses and 2-D elemental mapping results by micro-PIXE, heterogeneities in the concentrations of heavy metals within the analyzed aggregations of pyrite are exhibited. On the basis of the As and Pb zoning patterns, the time range and chronological stages of pyrite-aggregation growth are revealed.

DOI： 10.1007/s12665-012-1966-7

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Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)   Publisher：[地盤工学会]  

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DOI： 10.14863/geosocabst.2012.0_310

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Phytoremediation is an environmental remediation technique that takes advantage of plant physiology and metabolism. The unique property of heavy metal hyperaccumulation by the macrophyte Eleocharis acicularis is of great significance in the phytoremediation of water and sediments contaminated by heavy metals at mine sites. In this study, a field cultivation experiment was performed to examine the applicability of E. acicularis to the remediation of water contaminated by heavy metals. The highest concentrations of heavy metals in the shoots of E. acicularis were 20 200 mg Cu/kg, 14 200 mg Zn/kg, 1740 mg As/kg, 894 mg Pb/kg, and 239 mg Cd/kg. The concentrations of Cu, Zn, As, Cd, and Pb in the shoots correlate with their concentrations in the soil in a log-linear fashion. The bioconcentration factor for these elements decreases log-linearly with increasing concentration in the soil. The results indicate the ability of E. acicularis to hyperaccumulate Cu, Zn, As, and Cd under natural conditions, making it a good candidate species for the phytoremediation of water contaminated by heavy metals.

DOI： 10.1002/clen.201000488

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

Eleocharis acicularis was exposed to different concentrations of In, Ag, Pb, Cu, Cd, and Zn in the laboratory to assess its capability in accumulating these metals. After 15 days, 477 mg/kg dry wt. of In was accumulated by the roots; concentrations of Ag, Pb, Cu, Cd, and Zn in the shoots were 326, 1120, 575, 195, and 213 mg/kg dry wt., respectively. The results indicate that E. acicularis has the ability to accumulate these metals from water, making it a good candidate species for phytoremediation and phytomining. (C) 2010 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.biortech.2010.10.014

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This study was conducted to evaluate the phytoremediation and phytomining potential of 10 plant species growing naturally at one of the largest lead-zinc mines in Northern Vietnam. Total concentrations of heavy metals and arsenic were determined in the plant and in associated soil and water in and outside of the mine area. The results indicate that hyperaccumulation levels (mg kg(-1) dry weight) were obtained in Houttuynia cordata Thunb. (1140) and Pteris vittata L (3750) for arsenic, and in Ageratum houstonianum Mill. (1130), Potamogeton oxyphyllus Miq. (4210), and P. vittata (1020) for lead. To the best of our knowledge, the present paper is the first report on metal accumulation and hyperaccumulation by H. cordata, A. houstonianum, and P. oxyphyllus. Based on the obtained concentrations of metals, bioconcentration and translocation factors, as well as the biomass of these plants, the two latter species and P. vittata are good candidates for phytoremediation of sites contaminated with arsenic and multi-metals. None of the collected plants was suitable for phytomining, given their low concentrations of useful metals (e.g., silver, gallium, and indium). (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jhazmat.2010.12.020

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DOI： 10.14863/geosocabst.2011.0.271.0

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Language：Japanese   Publisher：Volcanological Society of Japan  

The Hirano volcanic ash in Nomura Town, southwestern Shikoku, Japan, has been characterized by petrography, refractive index and geochemical composition of volcanic glass (major and trace elements), and fission-track age of zircon. The Hirano volcanic ash has abundant vesicular glass shards and phenocrysts of biotite, hornblende and orthopyroxene. The volcanic glass has a rhyolitic composition. LREE (Light Rare Earth Element) profiles of the volcanic glass are steep with La/Sm_N=5.0-5.3 and those of HREE (Heavy Rare Earth Element) are flat with Gd/Yb_N=1.2-1.3. They have a weakly developed Eu anomaly. The Hirano volcanic ash has similar values of some incompatible trace element ratios, such as La/Y, Ba/La and Nb/Zr, with the Yufugawa pyroclastic flow deposit in the Ooita Prefecture. The fission-track age of 0.46±0.09Ma (1σ) was obtained for zircons from the Hirano volcanic ash. The Hirano volcanic ash can be correlated to the Yufugawa pyroclastic flow deposit based on petrographical, geochemical and geochronological data.

DOI： 10.18940/kazan.54.6_241

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

Sb, As, Cu, and Zn toxicity and contamination have become a growing concern in recent years. Phytoremediation, a plant based and cost effective technology, may be an effective approach in the cleanup of water contaminated by these metals. In this study, the aquatic macrophyte Eleocharis acicularis was used in laboratory and field experiments to assess its capability to accumulate Sb, As, Cu, and Zn, and thereby investigate its potential application in phytoremediation. The results showed that E. acicularis adapted well to water contaminated by these metals. The removal rates of Sb, As, Cu, and Zn in the laboratory experiment were 3.04, 2.75, 0.417, and 1.49 mu g/L/day, respectively. The highest concentrations of these metals accumulated in E. acicularis after 10 days of the laboratory experiment were 6.29, 6.44, 20.5, and 73.5 mg/kg dry weight, respectively. Only 8% of As, 12% of Sb, 87% of Cu and 93% of Zn removed from the water were used by E. acicularis. The highest concentrations of Sb, As, Cu, and Zn accumulated in E. acicularis after 10 wk of the field experiment were 76.0, 22.4, 33.9, and 266 mg/kg dry weight, respectively. The results indicate that E. acicularis has the ability to accumulate Sb, As, Cu, and Zn from contaminated water.

DOI： 10.1002/clen.200900061

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-V C H VERLAG GMBH  

Phytoremediation, a plant-based and cost-effective technology for the cleanup of contaminated soil and water, is receiving increasing attention. In this study, the aquatic macrophyte Eleocharis acicularis was examined for its ability to take up multiple heavy metals and its potential application for phytoremediation at an abandoned mining area in Hokkaido, Japan. Elemental concentrations were measured in samples of F. acicularis, water, and soil collected from areas of mine tailing and drainage. The results reveal that Pb, Fe, Cr, Cu, Ni, and Mn accumulation in the plants increased over the course of the experiment, exceeding their initial concentrations by factors of 930, 430, 60, 25, 10, and 6, respectively. The highest concentrations of Fe, Pb, Zn, Ni, Cr, Cu, and Ni within the plants were 59500, 1120, 964, 388, 265, 235, and 47.4 mg/kg dry wt., respectively, for plants growing in mine drainage after 11 months of the experiment. These results indicate that E. acicularis is a hyperaccumulator of Pb. We also found high Si concentrations in E. acicularis (2.08%). It is likely that heavy metals exist in opal-A within cells of the plant. The bioconcentration factors (BCF; ratio of metal concentration in the plant shoots to that in the soil) obtained for Cr, Cu, Zn, Ni, Mn, and Pb were 3.27, 1.65, 1.29, 1.26, 1.11, and 0.82, respectively. The existence of heavy metals as sulphides is thought to have restricted the metal-uptake efficiency of E. acicularis at the mine site. The results of this study indicate that E. acicularis shows great potential in the phytoremediation of mine tailing and drainage rich in heavy metals.

DOI： 10.1002/clen.200900009

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Language：Japanese   Publisher：The Geological Society of Japan  

A Jurassic accretionary complex within the Northern Chichibu Belt, Yanadani area, western Shikoku, is divided into three distinct geologic units (units I, II, and III) based on the constituent rocks and geologic structure. Unit I is characterized by pelitic melange containing blocks of greenstone, chert, limestone, and terrigenous clastic rocks. Unit II consists mainly of psammitic and pelitic phyllites, and Unit III consists of large blocks of greenstone-limestone complex with alternating beds of sandstone, mudstone, and pelitic melange. The contacts between the units are northward-dipping faults. Here, we propose a method of analyzing grading structure, and there by younging direction, which involves grain-size measurements under the microscope. The younging directions of coherent sequences and pillow lava were determined at 63 localities. These data reveal consistent younging directions within large-scale blocks, demonstrating that the strata of Units I and II, and the terrigenous clastic rocks of Unit III are overturned, younging to the south. In contrast, the greenstone-limestone complex within Unit III is not overturned, and youngs to the north. This large-scale overturned structure within the Northern Chichibu Belt is interpreted to represent a large-scale overturned fold.

DOI： 10.5575/geosoc.115.1

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DOI： 10.14863/geosocabst.2009.0.447.0

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPAN ASSOC MINERALOGICAL SCIENCES  

Framboidal pyrite in mudstone is known to be a reservoir of arsenic, yet few studies have conducted quantitative analyses of framboidal pyrite with ppm-level sensitivity. In this study, we used micro-PIXE to measure the concentrations of heavy metals in framboidal pyrite from drill-core samples of mudstone from the Late Cretaceous Hakobuchi Group, central Hokkaido, Japan. Pyrite framboids that OCCUr in polyframboids can be divided into two types based on framboid diameter (D) and the average diameter of microcrystals within framboids (d): type 1, being relatively small grains; and type 2, being relatively large grains. Higher concentrations of As are observed in most type 2 framboids than in type 1 framboids. High concentrations of Pb generally occur as isolated islands within type I framboids, concentrated along the rims of polyframboids. It could be concluded that contrasting formation processes among different framboids led to the observed changes in heavy metal concentrations.

DOI： 10.2465/jmps.071019

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Four volcaniclastic deposits from an outcrop in the eastern Tekeda City, Oita prefecture, southwestern Japan, have been investigated. Based on their mineral abundances, morphology and refractive indices of volcanic glass shards, four tephras correspond to Kuju Daiichi pumice fall (Kj-P1), Aira-Tn tephra (AT), Kikai-Akahoya volcanic ash (K-Ah) and Middle Danbaru scoria fall (DS) in ascending order.

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DOI： 10.14863/geosocabst.2008.0.511.0

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DOI： 10.5575/geosoc.113.S103

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The sporophyte of the fern Pteris vittata is known to be a hyperaccumulator of arsenic in its fronds to>2.3% of its dry weight. However, very little has been stated about hyperaccumulation of arsenic by gametophytes of P. vittata. Here we report that gametophytes of P. vittata from Beppu City and Okinawa Island in western Japan hyperaccumulate arsenic in a similar manner to that observed in the sporophyte. The gametophytes from the Beppu City are able to grow in medium containing 10mM arsenate and accumulate>1.8% of their dry weight as arsenic. The results suggest gametophytes of P. vittata also have a great potential to be used for phytoremediation and the relative ability of tolerance and accumulation show some local variation of their sources.

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：BLACKWELL PUBLISHING  

The low-grade metamorphosed Jurassic accretionary complex of the Northern Chichibu Belt, Hijikawa area, western Shikoku, is divided into two units, the Hijikawa and Kanogawa units, that are separated by an out-of-sequence thrust (OOST), the Ozu-Kawabegawa Fault. The Kanogawa unit south of the Ozu-Kawabegawa fault consists mainly of sandstone, shale, broken formation of alternating sandstone and shale, greenstone, chert, and pelitic melange, while the Hijikawa unit is characterized by a stack of subunits separated by small-scale thrusts. The subunits are mainly made up of basic, pelitic and psammitic semischists, schistose pelitic melange, and chert. Petrological and mineralogical constraints suggest peak metamorphic conditions of 204-247 degrees C at 1-3 kbar in the Kanogawa unit, and 228-289 degrees C at 3-5.6 kbar in the Hijikawa unit. Quartz and quartz-calcite veins are widely developed in the study area, especially in the Hijikawa unit. Regional variations in stable isotopic data show that the delta O-18(quartz) and delta O-18(calcite) values in veins tend to increase towards the Ozu-Kawabegawa Fault. The delta O-18(whole rock) values are remarkably high in some subunits close to OOSTs within the Hijikawa unit. Oxygen isotopic compositions from vein quartz indicate that a higher delta O-18 fluid migrated upward from depth along the Ozu-Kawabegawa Fault within the accretionary prism during prehnite-pumpellyite facies metamorphism. The fluid source is inferred to be pelitic rocks at higher temperatures and greater depths within the accretionary prism.

DOI： 10.1111/j1525-1314.2007.00701.x

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DOI： 10.14863/geosocabst.2007.0.255.0

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Publisher：日本地下水学会, 日本水環境学会, 廃棄物資源循環学会, 地盤工学会, 土壌環境センター  

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Language：Japanese   Publisher：日本地質学会  

Fission-track dating of zircon and volcanic ash analysis were carried out for Bannosu volcanic ash in the Bisan-seto Group around the Bannosu region in the northeast Shikoku. The first reliable radiometric age, 0.63±0.14 Ma (1σ), was obtained for the volcanic ash layer. On the other hand, the refractive indexes of the volcanic glasses show the 1.5004-1.5071 (mode: 1.504-1.506). On the basis of these values and other petrographical data, this volcanic ash layer is correlated to the Kb-Ks volcanic ash. These results are important to discuss the sedimentary environment of the Seto Inland Sea in Pleiocene to Holocene.

DOI： 10.5575/geosoc.112.608

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Language：English   Publisher：The Geological Society of Japan  

DOI： 10.5575/geosoc.112.10.XIX_XX

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Tephra is an important natural laboratory for studying processes of magma genesis and eruption. The analysis deficit generally reflects accidental intersection of mounting epoxy adjacent to glass fragments or of unseen microvesicles within glass fragments by the analytical beam. Low totals of the analysis are more common in fine-grained samples (<0.25mm). In this study, quantitative chemical analysis on fine-grained volcanic glass shards (<0.25mm) has been carried out by new technique for mounting small volcanic glass shards. Thin Cu sheet has been used for mounting glass shards. Volcanic glass must be polished until its thickness become about half in pits of the Cu sheet. The result suggests that this method is available for the quantitative analysis of fine-grained glass shards (<0.25mm).

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Language：Japanese   Publisher：Ehime University  

Olivine-orthopyroxene-andesite in Tobe Town, Ehime Prefecture, Japan has been investigated based on geology and petrology. It intrudes into the Mannen altered andesite but it has not undergone hydrothermal alteration. The olivine-orthopyroxene-andesite contains Mg-rich olivine and orthopyroxene and Cr-rich chromite. It is a high-Mg andesite (HMA) based on petrography and bulk rock chemistry. From the effect of the hydrothermal alteration the age of the intrusion is inferred to be immediately after the hydrothermal alteration of the Mannen altered andesite.

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Abundance of trace elements including toxic heavy metals in water along the Tobe River system are determined by inductively coupled plasma-mass spectrometry (ICP-MS) to identify the origin of high contents of arsenic and antimony in the water around the area. Based on our new data, the highest contents of arsenic and antimony come locally from any groundwater related to the abandoned Koboshi-mine, in which mines mainly stibnite (antimony). The high abundances of the elements are diluted with increase of water volume. As the results, arsenic content through the river system becomes below the 0.01mg/L considered to be environmental criteria. On the other hand, the antimony content in the water is still too high as compared to item to be monitored. This is consistent with results of the previously reported value. We need further monitoring of the antimony contents through the river system.

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We determined trace element abundance in twenty seven ferns and related lichen from the Mannen area, Tobe Town, Ehime Prefecture, to find plants for phytoremediation. Although the most ferns do not show specific accumulation for any toxic elements, Arachniodes standishii (Moore) Ohwi contains significant amount of antimony (max. 44μg/g-DW). Further greenhouse pot experiment is needed to test the possibility for the fern as the accumulator.

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Tourmaline-bearing amphibolite was found in the Kokuryogawa area, central Shikoku, Japan as rolling stones from Tonaru amphibolite mass. They can be devided into three types; Type 1; tourmaline in garnet-kyanite-horlnblendite. Type 2; vein tourmaline in rock, and Type 3; tourmaline in quartz vein of amphibolite. Tourmaline compositions of type 1 and 2 are high X_<Mg> (0.70-0.83; 0.83-0.87, respectively) although those of type 3 is comparatively low dravite component (X_<Mg> 0.60-0.64). Compositional fields of type 1 and 2 correspond to that of tourmaline in oligoclase-biotite zone of Tonaru area. It is inferred that the tourmalines were formed during the Sanbagawa metamorphic peak and retrograde metamorphism.

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The Japanese Association of Mineralogists, Petrologists and Economic Geologists, The Mineralogical Society of Japan and Ehime University held the open symposium on asbestos problem at Ehime University in September, 2005. Asbestos is a fibrous mineral that is chemically inert with heat resistant properties and has been used in over 3000 products for fire proofing, thermal, electrical and sound insulation, plasters, roof and flooring materials, gasket and friction products. However, the inhalation of asbestos fibers causes various serious illnesses of the lungs. Most uses of asbestos are prohibited in many countries. We would like to widely introduce the asbestos and its related problem and contribute the answer of this problem in some way.

DOI： 10.2465/gkk.35.1

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Publisher：日本地下水学会, 日本水環境学会, 廃棄物資源循環学会, 地盤工学会, 土壌環境センター  

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The term asbestos is a generic designation given to six types of naturally occurring mineral fibers that are or have been used in commercial products. These fibers belong to two mineral groups: serpentines and amphiboles. The serpentine group contains a single asbestiform variety: chrysotile. The amphibole group contains five asbestiform amphibole varieties: anthophyllite, grunerite (amosite), riebeckite (crocidolite), tremolite and actinolite.<br>     These fibrous minerals share several properties which qualify them as asbestiform fibers. They are bundles of fibers which can be easily cleaved into thinner fibers. Several properties that make asbestos so versatile and cost effective are high tensile strength, chemical and thermal stability, high flexibility, and low electrical conductivity.<br>     Asbestos fibers have been used in a broad variety of industrial application; some 3000 applications such as roofing products, gaskets, and friction products. 80% of imported asbestos is used for cement products such as asbestos boards and slates which are used for building materials, 7% for friction materials, and less than 3% for asbestos textile. Nearly all of the asbestos produced worldwide is chrysotile. Historically, chrysotile has accounted for more than 90% of the world's asbestos production, and it presently accounts for over 99% of the world production. Two types of amphiboles, commonly designated as amosite and crocidolite are no longer mined. With the onset of the health issues concerning asbestos in the late 1960s and early 1970s, world production and consumption began to decline during the 1980s. Japan used approximately 6.7 million tons between 1974 and 2004. About 67% of this amount was used since 1930.<br>     The relationship between workplace exposure to airborne asbestos fibers and respiratory diseases is one of the most widely studied subjects of modern epidemiology. The research efforts resulted in significant consensus that asbestos fibers can be associated with diseases of asbestosis, lung cancer and mesothelioma. Its carcinogenic nature, an overall lack of knowledge of minimum safe exposure levels, and the long latency for the development of lung cancer and mesothelioma are the main contributing factors to these controversies.

DOI： 10.2465/gkk.35.3

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DOI： 10.14824/jampeg.2005.0.107.0

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Mine drainage and yellowish brownish precipitation (so called "yellow boy") in the Ichinokawa mine, Saijyo City, Ehime prefecture, Japan, have been geochemically investigated. The mine drainage reaching the Ichinokawa River originates in the Senga gallery of the Ichinokawa mine. The Ichinokawa mine drainage is characteristically high in arsenic and exceeds the water-quality standard on arsenic. The yellowish brownish precipitation is characterized by high iron, arsenic and antimony contents. It is supposed that the Ichinokawa mine drainage has been formed by pyrite weathering. The drainage does not have a negative impact on the water quality of the Ichinokawa River. However, the Ichinokawa rivers may be degraded by the Ichinokawa mine drainage in future.

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Phytoremediation is the use of plants for the in situ cleanup of contaminated soils, sediments, and ground water. Pot-scale experiment evaluated phytoremediation by Pteris vittata L. (Chinese brake fern) for mudstone containing arsenic (12.3 mg/kg-DW) of the Hakobuchi Group in the Yubari City, central Hokkaido, Japan. In this experiment, fronds of Pteris vittata L. were taken after 18 weeks growth in soil. The following properties became clear after examining the experimental results. (1) The brake fern can growth in the soil made from mudstone containing arsenic. (2) The highest arsenic concentrations in the frond of Pteris vittata L. growing in the soil are about 3000 mg/kg-DW. (3) The fern removed arsenic about 10 % from mudstone. The results suggested that the brake fern has a great poten tial to be used for phytoremediating soils with low concentration of arsenic.

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Arsenic hyperaccumulation and tolerance in gametophytes and spores ofPteris vittata L. (brake fern) have been investigated. Gametophytes are able to grow normally in medium containing 50 to 200 or 300 μM arsenite and arsenate. In medium containing <300 μM arsenite and 500 μM arsenate, gametophytes do not almost grow. The highest arsenic concentrations in gametophytes are about 1,023 and 920 mg/kg-DW in medium containing 300 μM of arsenite and arsenate. The results suggest that gametophytes of the brake fern also has a great potential to be used for phytoremediating soils with low concentration of arsenic.

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In this paper, formation process of Ichinokawa breccia and antimony-arsenic mineralization in the breccia in the Ichinokawa area of Saijyo City, Ehime Prefecture, Japan, has been studied on the basis of geological, petrological and geochemical data. We have focussed on "hydraulic fracturing" process for the genesis of the Ichinokawa conglomerate. Ichinokawa conglomerate can be divided mainly into Ichinokawa breccia and Myojin Group. Carbonate-rich breccia and sandstone filling fractures are also found in the Sanbagawa schists adjacent to the Ichinokawa breccia. High-angle breccia zones, the Ichinokawa breccia, cut across the Sanbagawa schistocity. The Ichinokawa breccia consist principally of breccias which have been partly altered and veined by quartz, carbonate minerals and pyrite, and matrix of carbonate-rich sandstone. Schist clasts (up to 10 m across) in the breccia are angular but not variably rotated. Breccias are both clast- and matrix-supported and show evidence for single fracturing and healing by hydrothermally precipitated minerals such as carbonate minerals, pyrite, stibnite, pyrite and quartz. Two Sb and As-rich zones in the Ichinokawa breccia along the Ichinokawa River are about 10-30 m wide adjacent to the Sanbagawa schists. As and Sb values of carbonate matrix in the breccia are extremely high. These observations suggest that the the Ichinokawa breccia formed through a hydrofracturing process associated with hydrothermal fluid infiltrated into Sanbagawa metamorphic as precursor of the antimony ore forming. Hydrothernal fluid seems to have caused mineralization of carbonate minerals and sulfide minerals. Afterwards, the Myojin Group was accumulated above on the Ichinokawa breccia.

File： AN10408332_2005_11-09.pdf

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Precise quantitative analyses of arsenic for a small amount of dried plant samples (〜10 mg) by instrumental neutron activation analyses (INAA) and inductively coupled plasma-mass spectrometry (ICP-MS) were developed to evaluate environmental purification of soil and water by phytoremediation technique. To confirm the reliability of the analytical methods, we measured standard material NIES No.l (pepperbush). Obtained arsenic contents of the NIES No.l by INAA and ICP-MS were 2.18 ± 0.03 μg/g-DW and 2.25 ± 0.03 μg/g-DW, respectively. Both results agree well with the certificated value of the NIES standard (2.3 ± 0.3 μg/g-DW). Results by both analytical methods for the higher arsenic contents ofPteris vittata L. (〜4,000 μg/g) were also satisfied to confirm the accuracy. Consequently, we conclude that both quantitative analytical methods are appropriate for determine the wide range of arsenic content in small amount of plant samples.

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Mode of occurrences of sulfide minerals and As concentrations of samples from a horizontal boring core of Mannen altered andesite in the Tobe Town, Ehime Prefecture, Japan, has been investigated based on petrography, mineralogy and geochemistry. The Mannen altered andesite intrudes into the vicinity of boundary between the Sanbagawa metamorphic rocks and the Middle Miocene Kuma group. The andesite body has undergone extensive hydrothermal alteration, and has domains of a high concentration of As, S and Sb. Index alteration minerals are pyrite, arsenopyrite, marcasite, stibnite, quartz, opal, carbonate minerals, chlorite, illite and kaolinite. In the Mannen arrear textures of sulphide minerals can be divided into the following six types; sparse, sand spot pool and vein, and black-ink-drawing types. The black-ink-drawing type is characterized by the abundance in marcasite and arsenopyrite. The high concentration domains in arsenic are in general agreement with that characterzed by sulphide minerals of the black-ink-drawing type. Sb, S and As are extremely added and Na_2O, MgO, CaO and FeO are depleted in the Mannen andesites during the hydrothermal alteration on the basis of isocon analyses.

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The weathering process of Mannen altered andesite in Tobe Town, Ehime Prefecture, Japan, has been investigated based on geology, petrography and geochemistry. The Mannen andesite intrudes into the Sanbagawa metamorphic rocks and the Middle Miocene Kuma group. The andesite dyke have undergone extensive hydrothermal alteration and mineralization, and has domains of a high concentration of As, S and Sb. Index alteration minerals are pyrite, arsenopyrite, marcasite, stibnite, quartz, carbonate, chlorite, titanite and illite. The weathering types in the near surface of the Mannen andesite is divided into five based on the degree of progress of weathering. That results show that domains of sulphide minerals-rich altered andesite are extremely weathered. CaO, Fe_2O_3, MgO, Pb, Cu, Sb, S and As are depleted in weathered parts of the Mannen andesite based on isocon analysis. Especially, Fe_2O_3, S and As are extremely depleted in weathered parts of sulphide minerals-rich altered andesites. It shows that sulphide minerals in the andesite are decomposed by interaction of surface water and microbial activity, and these elements are leaching away to surrounding environments.

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Seventeen trace element abundance (Li, Al, V, Cr, Mn, Co, Ni, Cu, Zn, Ga, As, Rb, Sr, Cd, Cs, Ba and Pb) for 4 fountains and 8 river waters derived from the high As-bearing Mannen andesite body, Tobe-town, Ehime prefecture, were determined for environmental assessment by inductively coupled plasma-mass spectrometry (ICP-MS). We had predicted high arsenic contents in the surface waters, because the local geologic background contains extremely high arsenic content (max. 1200 ppm As). The arsenic contents in the waters are low (<3.5 ng/g) contrary to our expectations, which the concentrations of the arsenic are below the environmental standard (<10 ng/g As). However, there is still in danger of increasing the arsenic contents by abrupt environmental change such as expansion project of road and tunnel in the area. The construction may produce large amount of rock debris including abnormally high arsenic. Consequently, further weathering of the debris at the surface condition must cause new liquation into surface water of arsenic from the rock. On the other hand, river water around the former Choshi-daki sulfide-ore Mine in the andesite body contains abnormally high zinc content (ca. 200 ng/g). This must be influenced by solve out of zinc ions to the water from the country rock. We need further environmental monitoring for the water condition.

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Language：Japanese   Publisher：愛媛大学  

Geology and hydrothermal alteration of the Mannen altered andesite in Tobe Town, Ehime Prefecture, Japan, has been investigated based on field survey and petrography. The Mannen andesite intrudes into the Sanbagawa metamorphic rocks and the Middle Miocene Kuma group after the formation of breccia including only clasts of the Sanbagawa basic schist. The Mannen andesite body have undergone extensive hydrothermal alteration and mineralization. The alteration is characterized by the occurrences of quartz, illite, kaolinite, carbonates, chlorite, anaterze, pyrite, arsenopyrite, marcasite, stibnite and chalcopyrite. The texture of sulfide minerals can be divided into five types, sparse, sand, spot, vein and pool, black-ink-drawing types on the basis of the mode of occurrences of sulfide minerals.

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Language：Japanese   Publisher：The Geological Society of Japan  

Basement structure and Quaternary stratigraphy under the Horie lowland which is narrow and NNW-SSE-trending at the north of the Matsuyama Plain, northwestern Shikoku, have been investigated on the basis of drilling data and Bouguer anomaly. The basement structure of the Horie lowland is characterized by an asymmetric basin which has a step of depth of basement surface along the western margin of the lowland. The distribution of Bouguer anomaly is in good agreement with the basement structure. The basement structure can be traced as far as the Shigenobugawa River in the south of the Matsuyama Plain from the Bouguer anomaly data. The deposits under the Horie lowland are thinned eastward from the step. The deposits under the Horie lowland can be divided into five formations based on sedimentary faces. They are composed mainly of gravel, sand, silt and clay that are intercalated with thin tuff beds. The basal formation is tilted to the west at an angle of 98/1000. The tilting angle becomes gentle in ascending order. These geophysical and geological data indicate that the Horie lowland is characterized by a half-graben structure with a NNW-SSE-trending normal fault, the Horie fault, along the western margin. It has been estimated that the Horie fault is extended to south of distribution area of the Median Tectonic Line active fault system and had been active during the Pleistocene.

DOI： 10.5575/geosoc.110.746

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Language：Japanese   Publisher：公益社団法人地盤工学会  

Volcanic rock and sedimentary rock often contain heavy metal. Heavy metal gives bad influence to health of human body. In general, excavation gravel containing heavy metal is processed by interception using sheet. But durability of sheet is not eternity. We examined chemical tecnique by rock or clay replacing with sheet. Some materials such as sandstone or kaolin clay reduce quantity of dissolution of heavy metal from excavation gravel. In the future, it is important to use materials of nature in order to intercept the diffusion of heavy metal.

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Language：Japanese   Publisher：愛媛大学  

The results of quantitative chemical analysis on volcanic glass shards are discussed with examination of analytical technique. The apparatus being used is Oxford Link ISIS energy dispersion X-ray microanalyzer (EDS) with JEOL JSM-5400 scanning electron microscope (SEM). Some analyzed samples are AT ash in the Sadohara-cho, Miyazaki Prefecture and Hirano tephra in the Nomura-cho, Ehime prefecture. The results show that (1) The available finest 15kV acceralation voltage, 4.00×10^^&lt;-10&gt;A beam current of exposed electron beam and 30 seconds of acquisition live time, (2) the volcanic glass shards show low K_2O contents in the edge, which is changed in quality, (3) analytical technique is that the use of polished internal surface of glasses until a thickness of glass shards become about half, (4) The data of glass shard should be checked and selected by H_2O contents.

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Language：English   Publishing type：Research paper (bulletin of university, research institution)  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：News of Osaka Micropaleontologists  

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DOI： 10.5575/geosoc.109.XXIII

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DOI： 10.5575/geosoc.108.XIII

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DOI： 10.5575/geosoc.107.XXI

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Language：English   Publisher：The Geological Society of Japan  

A corona is a small-scale structure developed around a mineral grain by reaction with its surroundings. It could indicate a change in chemical and/or physical factors during a prograde or retrograde metamorphic event, or associated with cooling from igneous temperatures (Kretz, 1994). The olivine-plagiocalse corona is one of distinct and most common examples of them in metamorphosed rocks.<BR>In Ontario, the Grenville Orogen comprises the Central Gneiss Belt and the structurally overlying Central Metasedimentary Belt, divided into a northeastern Elzevir terrane and a southeastern Frontenac terrane. The Chenaux gabbro intrusion is one of plutons in the Raglan gabbro belt at the base of the Elzevir terrane hanging wall (Pehrsson et al., 1996) (Fig.1). It was emplaced during the late stage of the regional metamorphism and deformation, culminated at ca.1.1 Ga.<BR>The Chenaux Gabbro is partly deformed and recrystallized on the amphibolite facies condition. Intrusive contacts between the gabbro and surrounding carbonate rocks are observed at various places (Fig.2 (1)). It has occasionally igneous layering (Fig.2 (2)). The principal constituents of the gabbro are plagiolclase, olivine, clinopyroxene, orthopyroxene and calcic amphiboles, with small amounts of biotite, spinel and Fe-Ti oxides.

DOI： 10.5575/geosoc.107.IX

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The Omogiyama hornfels is one of the hornfelses sporadically occurring in the Sanbagawa metamorphic belt, central and western Shikoku, southwest Japan. They are originated from the Sanbagawa basic schists and distributed parallel to its schistosity. Large igneous bodies have not been found around the hornfels. The hornfelses are characterized by the assemblage of hornblende + actinolite + biotite + plagioclase + quartz. Based on the lack of large igneous rocks and the mode of occurrence of the Omogiyama hornfels, it seems that the hornfels was formed by high-temperature fluid flow along the schistosity of the Sanbagawa basic schists.

DOI： 10.5575/geosoc.106.244

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEOCHEMICAL SOC JAPAN  

Chemical characteristics of "diagenetic" and "hydrogenous" type deep-sea nodules from the central and northeastern Pacific were studied regarding their Ce anomalies and Y fractionation from heavy REE. Pacific nodules of both types show low Y/Ho ratios less than average shales or chondrites, contrasting to the other marine samples (seawaters, limestones, and phosphorites) having higher Y/Ho ratios than average shales or chondrites. The "hydrogenous" type nodules show large positive Ce anomalies up to log(Ce/Ce*) = +0.6, whereas the "diagenetic" type nodules display only small positive Ce anomalies or even small negative ones. Two nodule subsamples, which are characterized by 10 Angstrom manganate but are chemically the intermediate between the two types, show Ce anomalies of log(Ce/Ce*) = +0.3 in the middle of the two end members. Interestingly, the Ce anomalies of the nodules vary coherently with their logarithmic Co/(Ni+Cu) ratios. This positive correlation is valid even after combing many literature data of Pacific nodules with our data. In the plot of Ce anomaly vs, log[Co/(Ni+Cu)], the three distinct types of Pacific nodules are systematically distinguished: "suboxic-diagenesis" less than or equal to "diagenetic" less than or equal to "hydrogenous". The systematics strongly suggest that: (i) the Ce anomaly and log[Co/(Ni+Cu)] are similar geochemical indexes showing how effectively oxidative uptake of Ce and Co occurred in each nodule relative to nonoxidative uptake of nutrient-type metals in the respective metal groups, and (ii) there exists an initial source supplying metals common to all the types of Pacific nodules. We inferred from various reasons that the common initial source is biogenic particulates delivered from overlying surface water. Oxidative uptake of Ce and Co by fast sinking large biogenic particulates is less effective, but such particulates can more effectively convey nutrient-type metals involved with them to the sea floor because of their shorter residence time in oxic water. However, the relationship between metal transports of scavenged- and nutrient-type elements is reversed in the case of slowly sinking biogenic particulates. High surface productivity inevitably provides high flux of fast sinking large organic particulates, whereas low productivity gives rise to organic particulate flux dominated by slowly sinking small ones. These mechanisms explain the observed systematics of Ce anomaly vs. log[Co/(Ni+Cu)] plots for Pacific nodules.

DOI： 10.2343/geochemj.33.399

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Language：Japanese   Publisher：The Association for the Geological Collaboration in Japan  

The Biei Complex, consisting a part of the Mesozoic accretionary complex called "Kamuikotan Belt" in the Sorachi-Yezo Belt of the central Hokkaido, is divided into four units as follows. Unit A is a crystalline schist unit composed of pelitic and siliceous schists. Unit B, metamorphosed greenstone unit, is subdivided into three metamorphic subunits ranging from prehnite-pumpellyite facies to amphibolite facies of low-pressure type. Metamorphic age is determined by K-Ar method (white mica) as 114-117 Ma. Unit C is the mixed unit of weakly metamorphosed greenstones and minor amount of siliciclastics. Peculiar veneer mixed structure named "sumi-flow (sumi-nagashi) structure" observed within Unit C. This type of mixed unit seems to be formed as a result of slicing and duplexing of subducted oceanic slab. Unit D consists of non-deformed greenstones. These four units tectonically contact with each other. Especially, Unit D overlies Unit B and Unit C with a remarkable thrust boundary, and forms "Oichan Nappe". Unit A is traceable continuously northward to the type Kamuikotan Metamorphic rocks in the Kamuikotan Gorge area. Unit B is equivalent to the Horokanai Ophiolite (Sorachi Group) suffered ocean floor metamorphism. Both Units C and D can be correlated to the Iwashimizu Complex.

DOI： 10.15080/agcjchikyukagaku.52.6_433

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Language：Japanese   Publisher：The Association for the Geological Collaboration in Japan  

The Biei Complex, consisting a part of the Mesozoic accretionary complex called "Kamuikotan Belt" in the Sorachi-Yezo Belt of the central Hokkaido, is divided into four units as follows. Unit A is a crystalline schist unit composed of pelitic and siliceous schists. Unit B, metamorphosed greenstone unit, is subdivided into three metamorphic subunits ranging from prehnite-pumpellyite facies to amphibolite facies of low-pressure type. Metamorphic age is determined by K-Ar method (white mica) as 114-117 Ma. Unit C is the mixed unit of weakly metamorphosed greenstones and minor amount of siliciclastics. Peculiar veneer mixed structure named "sumi-flow (sumi-nagashi) structure" observed within Unit C. This type of mixed unit seems to be formed as a result of slicing and duplexing of subducted oceanic slab. Unit D consists of non-deformed greenstones. These four units tectonically contact with each other. Especially, Unit D overlies Unit B and Unit C with a remarkable thrust boundary, and forms "Oichan Nappe". Unit A is traceable continuously northward to the type Kamuikotan Metamorphic rocks in the Kamuikotan Gorge area. Unit B is equivalent to the Horokanai Ophiolite (Sorachi Group) suffered ocean floor metamorphism. Both Units C and D can be correlated to the Iwashimizu Complex.

DOI： 10.15080/agcjchikyukagaku.52.6_433

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Language：Japanese   Publisher：日本地質学会  

DOI： 10.5575/geosoc.104.XXI

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Language：Japanese   Publisher：日本地質学会  

DOI： 10.5575/geosoc.104.563

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DOI： 10.5575/geosoc.104.604

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DOI： 10.5575/geosoc.104.604

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Language：Japanese   Publisher：The Geological Society of Japan  

DOI： 10.5575/geosoc.104.634

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DOI： 10.5575/geosoc.104.634

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Other Link： http://hdl.handle.net/10191/6267

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DOI： 10.5575/geosoc.104.590

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Language：Japanese   Publisher：Japan Association of Mineralogical Sciences  

Metamorphic biotites have been found from the pumpellyite-actinolite facies basic semischists in the northern Chichibu Belt, western Shikoku, Japan. Representative mineral assemblages of the northern Chichibu basic semischists in the study area are chlorite+phengite+calcite, riebeckite+phengite+chlorite+calcite, riebeckite+stilpnomerane+chlorite+calcite, biotite+riebeckite+chlorite+calcite and biotite+riebeckite+phengite+chlorite+calcite. Albite, titanite, hematite and quartz are common. The biotites occur in high-MgO basic semischists and are rich in phlogopite content. The mineral parageneses systematically change depending on MgO/(MgO+FeO) of bulk compositions.<br>     The bioitite-calcite-bearing basic semischists were metasomatically altered based on petrographical and geochemical data. The isocon diagram suggests that CaO and MgO were added in significant amounts and Na₂O, K₂O and P₂O₅ were removed. It seems that the increase in MgO due to metasomatism is a cause of the formation of biotite under the pumpellyite-actinolite facies.

DOI： 10.2465/ganko.93.291

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Language：Japanese   Publisher：The Japanese Association for Petroleum Technology  

Fission track fading in apatite has been measured in samples from the Shin-Yahiko-1 well, which is situated in a very young sedimentary basin in Japan. Fission track densities were too low to detect confined fission tracks, and consequently semi-track lengths were measured directly instead.<br>Mean lengths and frequency distribution of semi-tracks decrease clearly and progressively with increasing temperature and depth below 4, 400m, and the fading zone of semi-tracks spans an interval of less than 1, 500m, and 40°C in temperature.<br>The smooth trend of fission track fading in the Shin Yahiko-1 well suggests a relatively simple subsidence burial history, which is concordant with the burial history roughly estimated from ages of planktonic foraminifers.<br>From the Shin Yahiko-1 well data, fission track fading over a a very short effective heating time (0.05Ma) delineates a zone on the vitrinite reflectance nomograph.<br>GC/MS analysis suggests that the oil produced from the Shin Yahiko-1 originated from the highly matured Teradomari Formation, which occurs at a depth greater than 4, 500m and roughly corresponds to the top of apatite fission track fading zone.<br>Semi-track length measurement is useful as a supplementary thermal indicator even for very young basins, especially in igneous basement rocks where vitrinites are absent.

DOI： 10.3720/japt.62.544

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：BLACKWELL SCIENCE INC  

The Susunai Complex of southeast Sakhalin represents a subduction-related accretionary complex of pelitic and basic rocks. Two stages of metamorphism are recognized: (1) a local, low-P/T event characterized by Si-poor calcic amphiboles; (2) a regional, high-P/T event characterized by pumpellyite, actinolite, epidote, sodic amphibole, sodic pyroxene, stilpnomelane and aragonite. The major mineral assemblages of the high-P/T Susunai metabasites contain pumpellyite + epidote + actinolite + chlorite, epidote + actinolite + chlorite, epidote + Na-amphibole + Na-pyroxene + chlorite + haematite. The Na-amphibole is commonly magnesioriebeckite. The Na-pyroxene is jadeite-poor aegirine to aegirine-augite. Application of empirically and experimentally based thermobarometers suggests peak conditions of T = 25-300 degrees C, P = 4.7-6 kbar. Textural relationships in Susunai metabasite samples and a petrogenetic grid calculated for the Fe3+-rich basaltic system suggest that pressure and temperature increased during prograde metamorphism.

DOI： 10.1111/j.1525-1314.1997.00037.x

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Fe and Mn distribution in the pumpellyite group minerals (W(8)X(4)Y(8)Z(12)O(56-n),,(OH).) has been studied by using Fe-57 Mossbauer spectroscopy. The studied Fe-pumpellyites, belonging to the pumpellyite-julgoldite series, were collected from two localities; metabasites in the Tokoro belt, Hokkaido, and gabbroic sills in the Shimane Peninsula, Japan. Okhotskite, an Mn3+-dominant pumpellyite group mineral, was separated from the ores of metamorphosed manganiferous iron ore deposits in the Tokoro belt. Fe-57 Mossbauer spectrum of Tokoro Fe-pumpellyite is composed of two Fe2+- and two Fe3+-doublets. On the basis of the single crystal structure refinements of Al-pumpellyites published so far, doublets were assigned to Fe-W(2+), (IS = 1.01 and QS = 2.,73 mm/s), Fe-X(2+) (IS = 0.97 and QS = 3.18 mm/s), Fe-X(3+):+ (IS = 0.29 and QS = 1.37 mm/s) and Fe-Y(3+); (IS = 0.36 and QS = 2.09 mm/s), where IS is isomer shift relative to a metallic iron absorber and QS is quadrupole splitting. The Mossbauer spectrum of the Mitsu Fe-pumpellyite is composed of three doublets assigned to Fe-X(2+) (IS = 1.14 and QS = 3.20mm/s), Fe-X(3+) (IS = 0.36 and QS = 1.13mm/s) and Fe-Y(3+), (IS = 0.37 and QS = 1.93mm/s). These assignments show strong preference of Fe3+ in the X-site. The Mossbauer spectrum of the okhotskite is composed of two doublets by Fe-X(3+) (IS = 0.37 and QS = 1.13 mm/s) and Fe-Y(3+) (IS = 0.42 and QS = 2.18 mm/s). The area ratio shows that Fe-X(3+):Fe-Y(3+) ratio is 94:6. On the basis of chemical and Mossbauer analyses, Mn-X(3+):Mn-Y(3+) ratio is given as 19:81, indicating stronger Y-site preference of Mn3+ than Fe3+, what is consistent with Jahn-Teller theory. Al, Mn3+ and Fe3+ prefer the Y-site in this order.

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DOI： 10.5575/geosoc.103.167

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Language：Japanese   Publisher：The Geological Society of Japan  

DOI： 10.5575/geosoc.103.953

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DOI： 10.5575/geosoc.103.47

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER VERLAG  

The Middle Miocene Tobe hornfels in the Sanbagawa metamorphic belt, western Shikoku, southwest Japan, is characterized by an abnormally steep metamorphic gradient compared with other hornfelses associated with intrusive bodies. The basic hornfels, originally Sanbagawa greenschist rocks, is divided into the following three metamorphic zones: plagioclase, hornblende, and orthopyroxene. The plagioclase zone is defined by the appearance of calcic plagioclase, the hornblende zone by the assemblage of hornblende+calcic plagioclase+quartz, and the orthopyroxene zone is characterized by the assemblage of orthopyroxene + clinopyroxene + plagioclase + quartz. Calcic amphibole compositions change from actinolite to hornblende as a result of the continuous reactions during prograde metamorphism. Petrographical and thermometric studies indicate a metamorphic temperature range of 300-475 degrees C for the plagioclase zone, 475-680 degrees C for the hornblende zone, and 680-730 degrees C for the orthopyroxene zone. The temperature gradient based on petrological studies is approximately 5 degrees C/m, which is unusually high. Geological and petrological studies demonstrate that the hornfelses were formed by the focusing of high-temperature fluids through zones of relatively high fracture permeability. The steep thermal gradient in the Tobe hornfels body is consistent with a large fluid flux, greater than 8.3 X 10(-7) m(3) m(-2)S(-1), over the relatively short duration of metamorphism, approximately 100 years.

DOI： 10.1007/s004100050227

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Publisher：The American Geophysical Union  

DOI： 10.1029/94JB00958

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Language：English   Publisher：日本地質学会  

DOI： 10.5575/geosoc.100.575

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：American GEOPHYSICAL UNION  

Accretion of a large number of seamounts or fragments of huge oceanic plateaus is recorded in the geology of Japan. Major accretion occurred twice; a late Early Carboniferous seamount chain accreted in latest Permian to Middle Jurassic time, and a Late Jurassic oceanic plateau accreted in the Early Cretaceous. The Late Jurassic plateau now in northern Japan and Sakhalin is here named the ''Sorachi Plateau '' and a Tithonian age for it is well documented on the basis of microfossils from pelagic cherts and limestones. Petrochemical characteristics of basalts suggest two kinds of sources; depleted mantle under oceanic lithosphere and enriched mantle related to plume upwelling. All the accreted fragments in Japan can be traced back to the central part of the Panthalassa by using paleomagnetic data and plate ''trajectory analysis.'' The timing of generation of the accreted seamount chain and the plateau is consistent with a time of global change. Their place of origin, in the mid-Panthalassa, retains a positive residual geoid anomaly and slow Vp in the lower mantle, which suggest a past upwelling of hot material from the core-mantle boundary.

DOI： 10.1029/94TC00351

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DOI： 10.5575/geosoc.99.831

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DOI： 10.5575/geosoc.99.615

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Language：Japanese   Publisher：日本地質学会  

DOI： 10.5575/geosoc.99.335

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Language：Japanese  

Geology, metamorphic petrology and K-Ar age of the Tsuzuragawa hornfels in the Sanbagawa metamorphic belt, western Shikoku, were investigated. The basic hornfels, originally Sanbagawa green schist, are divided into three metamorphic zones; plagioclase zone, hornblende zone and orthopyroxene zone, based on their mineral assemblages. The plagioclase zone is defined by the appearance of calcic plagioclase. The hornblende zone is characterized by the appearance of hornblende + plagioclase. The assemblage in pyroxene hornfels are clinopyroxene + orthopyroxene + plagioclase + ilmenite at the orthopyroxene zone. The P-T path of the Tsuzuragawa hornfels corresponds to a metamorphic facies series of typical contact metamorphism. One K-Ar hornblende age of hornblende-biotite hornfels is 15.1 Ma. The Tsuzuragawa and genetically related hornfels should be thermally formed by the infiltration of high-temperature fluid along a large fracture in the Sanbagawa metamorphic rocks in or slightly prior to the Middle Miocene volcanism and plutonism.

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Language：English   Publishing type：Research paper (scientific journal)  

Abstract A deep section of accretionary complex, the metamorphosed Susunai Complex, is observed on Sakhalin Is., Russia. High pressure part of pumpellyite‐actinolite facies metavolcanics, metacherts and metapelites are well exposed and constitute a tectonic pile preserving primary structures related to underplating of the oceanic crust. Three stages of deformation, D1 through D3, suggest successive deformation during subduction, underplating and exhumation of the complex. Oceanic material in the complex is more abundant than other well documented ancient accretionary complexes (e.g. the Shimanto Belt in southwest Japan and the Ghost Rocks Formation in Alaska), which were shallowly underplated. At Susunai, deep down‐stepping of a décollément has scraped off the upper part of the oceanic crust, primarily the pillowed basalt horizon. This down‐stepping results from crustal weakening as overpressured water is released from the fractured oceanic crust during metamorphism. Copyright © 1992, Wiley Blackwell. All rights reserved

DOI： 10.1111/j.1440-1738.1992.tb00067.x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：OXFORD UNIV PRESS UNITED KINGDOM  

The metabasites within the Tokoro belt of eastern Hokkaido, Japan, suffered pervasive high-P/T metamorphism. Mineral assemblages and compositions of more than 400 metabasites from the Saroma-Tokoro district were investigated.
The metabasites are divided into six metamorphic zones based on mineral assemblages. The laumontite (Lm) zone is defined by the presence of laumontite. The prehnite-pumpellyite (Pr-Pp) zone is characterized by the association of prehnite + pumpellyite. The lawsonite-sodic pyroxene (Lw-Napx) zone is defined by the assemblage lawsonite + pumpellyite + sodic pyroxene + chlorite. The epidote-sodic pyroxene (Ep-Napx) (1) and (2) zones are characterized by the assemblage epidote + pumpellyite + sodic pyroxene + chlorite. The former is characterized by the absence of aragonite, sodic amphibole, and winchite, as well as the presence of jadeite-poor sodic pyroxene (max.Jd mol % = 13), whereas these minerals occur in the Ep-Napx(2) zone, together with jadeite-rich sodic pyroxene (max.Jd mol % = 34). In the epidote-actinolite (Ep-Act) zone, the most common assemblages contain epidote + actinolite + pumpellyite + chlorite.
The Lm zone corresponds to the zeolite facies (150-200-degrees-C and 1-2 kb) and the Pr-Pp zone is equivalent to the prehnite-pumpellyite facies (200-250-degrees-C and 2-2.5 kb). The Ep-Napx(1) zone appears to be stable at approximately 200-250-degrees-C and 2.5-3.5 kb. The pressure conditions in the Lw-Napx, Ep-Napx(2), and Ep-Act zones appear to range from 5 to 6 kb, and the temperatures are estimated to be 200-230, 230-270, and 270-300-degrees-C, respectively. The sequence of the metamorphic zones is characterized by the curved P-T path.
The stability field of pumpellyite + sodic pyroxene + chlorite in Fe3+-bearing metabasites is located in the lower-temperature and higher-pressure part of the pumpellyite-actinolite facies. On the basis of Schreinemakers' method, the stability field of the assemblage is bounded by a high-pressure reaction Pp + Napx + Chl + Ab + Qz +H2O = Lw + Gl, and by a high-temperature reaction Pp + Napx + Chl + Ab + Qz = Ep + Gl + H2O.

DOI： 10.1093/petrology/32.2.333

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Language：Japanese  

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Publisher：海洋出版  

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Language：Japanese   Publisher：The Geological Society of Japan  

DOI： 10.5575/geosoc.95.241

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Other Link： https://jlc.jst.go.jp/DN/JALC/00224918327?from=CiNii

Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER-VERLAG WIEN  

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Language：English   Publisher：Japan Association of Mineralogical Sciences  

The Jurassic Nikoro greenstones in the Tokoro district of the Tokoro Belt, eastern Hokkaido, Japan have suffered high-pressure intermediate type metamorphism. Aragonite is a widespread metamorphic mineral in the greenstones and has generally formed by patchy replacement of calcite. It is closely associated with pumpellyite, lawsonite, epidote, chlorite in quartz-carbonate veins or pools and scarcely sodic pyroxene, actinolite and winchite. The common occurrence of aragonite supports that the metamorphic facies series of the Nikoro Group is placed in a higherpressure part of the high-pressure intermediate group. It is supposed that the metamorphic aragonite has been formed by the prograde increase in pressure.

DOI： 10.2465/ganko1941.81.446

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

DOI： 10.1111/j.1525-1314.1986.tb00360.x

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Language：Japanese   Publisher：The Association for the Geological Collaboration in Japan  

DOI： 10.15080/agcjchikyukagaku.40.3_205

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Language：Japanese   Publisher：The Association for the Geological Collaboration in Japan  

The area investigated around Mt. Nikoro-yama is made up of the Mesozoic sedimentary and volcanic rocks which are divided into the Yubetsu Group, Nikoro Group, and Saroma Group. The Nikoro Group is composed mainly of greenstones such as basaltic and trachytic pillow lavas,, hyaloclastites, dolerite and trachyte dykes, ultramafic cumulates, and a small amount of chert and limestone. Volcaniclastic conglomerate, sandstone, siltstone, and shale are associated with the greenstones and are found in the Lower Part of the Nikoro Group. The volcanic piles of the Nikoro Group are considered as remnants of Jurassic seamounts from the following reasons; (1) explosive volcanism producing a large amount of hyaloclastite and strongly vesiculated pillow lavas, (2) alkali basalt magmatism from alkali olivine basalt to trachyte, (3) presence of volcaniclastic sedimentary rocks, and (4) lack of terrigenous sediments. Boulder and cobble conglomerate observed at the base of the Saroma Group irregularly covers greenstones of the Nikoro Group. No evidence of submarine basaltic volcanism is recognized in the Saroma Group composed entirely of clastic sedimentary rocks. The rapid change of lithofacies from the Nikoro to Saroma Groups as well as the distribution and occurrence of the basal conglomerate might indicate the presence of unconformity The basal conglomerate contains large numbers of well-rounded boulders and cobbles; 58〜78 modal % pyroxene andesite, 0〜10% hornblende andesite, 0〜2% rhyolite, 0〜4% monzonite, 0〜16% porphyritic monzonite, 0〜2% monzogabbro, 0〜2% slate and sandstone, 2〜4% trachyte, 5〜18% basalt and hyaloclastite. The abundance of calc-alkaline andesites and alkaline plutonics suggests that the materials have been derived mainly from a continental margin or an island arc. In this connection, it is noticed that the similar rock types are known in the Cretaceous formations of the Nemuro Group. Accordingly, the boulders and cobbles are considered to be originated in the Paleo-Kurile Arc in late Cretaceous time. At the time forming the unconformity, seamounts of the Nikoro Group might have been emplaced to the western margin of the Paleo-Kurile Arc, where a large amount of terrigenous elastics were supplied.

DOI： 10.15080/agcjchikyukagaku.38.6_408

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Responsible for pages：P51-88,89-100,604  

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Language：Japanese  

J-GLOBAL

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Language：Japanese   Publisher：Japan Society of Engineering Geology  

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Language：Japanese   Publisher：一般社団法人 日本地質学会  

DOI： 10.14863/geosocabst.2009.0.210.0

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Language：Japanese   Publisher：The Geological Society of Japan  

DOI： 10.14863/geosocabst.2008.0.469.0

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Language：Japanese   Publisher：The Geological Society of Japan  

DOI： 10.14863/geosocabst.2008.0.293.0

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Language：Japanese   Publisher：The Geological Society of Japan  

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Language：Japanese   Publisher：The Geological Society of Japan  

DOI： 10.14863/geosocabst.2008.0.513.0

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