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Multi-Scale Approach for Gold Targeting in Côte d’Ivoire Paleoproterozoic Rocks

Open Journal of Geology 2024年第2期14卷 155-176页

作者： Martial Pohn Koffi Adingra Yao Augustin Koffi N’guessan Nestor Houssou Zié Ouattara Tokpa Kakeu Lionel-Dimitri Boya Marc Ephrem Allialy training and research unit in earth sciences and Mineral resources Laboratory of Geology Mineral and Energy Resources University Felix HOUPHOU&#203T-BOIGNY Abidjan C&#244te d’Ivoire training and research unit in Geological sciences and mining Department of Geology and Material Man University Man C&#244te d’Ivoire

The aim of this study is to contribute to better targeting of gold prospecting areas using geospatial information. To this end, 3 mining sites were selected for the study. They are: the Sénoufo belt (Barrick Gold mine), the Yaouré complex (Perseus mining mine) and the South Fetêkro belt (Bonikro, Hiré and Agbaou mines). For this study, a multi-scale approach was carried out at regional, mine and microscopic levels. At the regional scale, a comparative analysis of 1:200,000 scale geological maps revealed that 3 main lithologies are regularly repeated on and around the various mining sites. These are: undifferentiated volcanics, metagranodiorites and metasiltites dominated by meta-arenites. Most of these lithologies are affected by undifferentiated faults generally oriented NE-SW, N-S, ENE-WSW and WNW-ESE. In addition, gold and manganese occurrences are present on all the sites studied. At the mine scale, radarsat-1 images processing indicate that the main mining sites are generally located near or at the intersection of lineaments-oriented NE-SW or N-S on the one hand and E-W or ENE-WSW or WNW-ESE or again NW-SE on the other. These mines are also located at the interface between zones of high and low lineament density. At the microscopic scale, petrographic studies of undifferentiated volcanic samples from the various sites indicate that they consist of andesites, meta-andesites and tuffs.

关键词： Gold Targeting Undifferentiated Volcanics Mineral Occurrences Lineaments Côte d’Ivoire

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Disaster effects of climate change in High Mountain Asia:State of art and scientific challenges Disaster effects of climate change in High Mountain Asia:State of art and scientific challenges

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Advances in Climate Change research 2024年第3期15卷 367-389页

作者： Hao WANG Bin-Bin WANG Peng CUI Yao-Ming MA Yan WANG Jian-Sheng HAO Yu WANG Ya-Mei LI Li-Jun SUN Jiao WANG Guo-Tao ZHANG Wei-Mo LI Yu LEI Wen-Qing ZHAO Jin-Bo TANG Chao-Yue LI Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China State Key laboratory of Tibetan Plateau earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Institute of Geographic sciences and Natural resources research Chinese Academy of SciencesBeijing 100101China China‒Pakistan Joint research Center on earth sciences Chinese Academy of SciencesIslamabad 45320Pakistan College of earth and Planetary sciences University of Chinese Academy of SciencesBeijing 100049China College of Atmospheric Science Lanzhou UniversityLanzhou 730000China National Observation and research Station for Qomolongma Special Atmospheric Processes and Environmental Changes Dingri 858200China

High Mountain Asia(HMA)shows a remarkable warming tendency and divergent trend of regional precipitation with enhanced meteorological *** rapid thawing of the HMA cryosphere may alter the magnitude and frequency of nature *** reviewed the influence of climate change on various types of nature hazards in HMA region,including their phenomena,mechanisms and *** reveals that:1)the occurrences of extreme rainfall,heavy snowfall,and drifting snow hazards are escalating;accelerated ice and snow melting have advanced the onset and increased the magnitude of snowmelt floods;2)due to elevating trigger factors,such as glacier debuttressing and the rapid shift of thermal and hydrological regime of bedrock/snow/ice interface or subsurface,the mass flow hazards including bedrock landslide,snow avalanche,ice-rock avalanches or glacier detachment,and debris flow will become more severe;3)increased active-layer detachment and retrogressive thaw slumps slope failures,thaw settlement and thermokarst lake will damage many important engineering structures and infrastructure in permafrost region;4)multi-hazards cascading hazard in HMA,such as the glacial lake outburst flood(GLOF)and avalanche-induced mass flow may greatly enlarge the destructive power of the primary hazard by amplifying its volume,mobility,and impact force;and 5)enhanced slope instability and sediment supply in the highland areas could impose remote catastrophic impacts upon lowland regions,and threat hydropower security and future water *** future,ongoing thawing of HMA will profoundly weaken the multiple-phase material of bedrock,ice,water,and soil,and enhance activities of nature *** and cascading hazards of high magnitude will prevail in *** the glacier runoff overpasses the peak water,low flow or droughts in lowland areas downstream of glacierized mountain regions will became more frequent and *** escalating hazards in the HMA region requires tackling s

关键词： High Mountain Asia Climate change Cryosphere degradation Nature hazards Disaster risk

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In-situ analysis and genetic investigation of Li-bearing minerals in McDermitt clay-type lithium deposit,Nevada,USA

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Acta Geochimica 2024年第3期43卷 478-488页

作者： Yi Cui Hanjie Wen Zhengbing Zhou Kunyue Ling Lin Xu Shirong Liu Fei Xu School of earth sciences East China University of TechnologyNanchang 330013China State Key laboratory of Nuclear resources and Environment East China University of TechnologyNanchang 330013China School of earth sciences and resources Chang’an UniversityXi’an 710054China College of earth and Planetary sciences University of Chinese Academy of SciencesBeijing 100049China State Key laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China State Key laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

Clay-type Li deposits are poised to play a pivotal role in addressing the surging global demand for *** McDermitt clay-type Li deposit,located in Nevada,is the largest Li deposit in the united States,with Li hosted by a clay-rich sequence of smectite-dominated intervals and illite-dominated intervals,***,the occurrence of Li and the genesis of Li-bearing minerals within smectite-dominated intervals have not been thoroughly investigated in previous ***,we studied the mineralogy,the in-situ Li distribution,and the bonding environments of Li within the smectite intervals using a combination of instru-mental techniques including scanning electron microscope,transmission electron microscope,time-of-flight secondary ion mass spectrometry,and nuclear magnetic *** results indicate that the smectite exhibits low crystallinity characteristics of lacustrine clay authigenesis and is com-monly found tofill the interstices among volcanic minerals or envelop them;Li is mainly hosted by Mg-smectite rather than the volcanic *** the tuffaceous sediment samples,the volcanic glass has undergone a transformation,resulting in its complete disappearance and alteration into clay *** to the octahedral sites of Mg-smectite bounded in Li,it is referred to be *** interpret that the hectorite’s precipitation occurs in a high saline-alkaline water environment,a result of McDermitt *** conclusion can be supported by the coexistence of spherulitic calcite and ***,this study confirms hectorite as the main Li-bearing mineral and increases the understanding of the genetic model of hectorite formation in intracontinental caldera basins.

关键词： McDermitt caldera Lithium occurrence Tuffaceous sediments Mineralogy Hectorite neoformation

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Holocene Hydroclimatic Variations in the Asian Drylands:Current Understanding and Future Perspectives

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Journal of earth Science 2024年第1期35卷 292-295页

作者： Guoqiang Ding Shengqian Chen Yuanhao Sun Shuai Ma Jianhui Chen MOE Key laboratory of West China's Environmental System College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China Alpine Paleoecology and Human Adaptation Group State Key Laboratory of Tibetan Plateau Earth SystemEnvironment and ResourcesInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

0 *** intensification of global warming is generating increasing risks to human society and sustainable development,which are of growing concern to the international scientific community and policymakers(Sun,2023).The ecosystems of the Asian drylands are fragile and highly sensitive to global changes;moreover,while these drylands are the most important areas of oasis agriculture on earth,their water resources are being adversely impacted by ongoing climate change(Zhang et al.,2023).Hence,an improved understanding of the patterns of climate change in this region is important and attracting increasing research attention.

关键词： Asian Holocene climatic

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A review of integrated surface-subsurface numerical hydrological models

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Science China earth sciences 2024年第5期67卷 1459-1479页

作者： Lele SHU Hao CHEN Xianhong MENG Yan CHANG Litang HU Wenke WANG Longcang SHU Xuan YU Christopher DUFFY Yingying YAO Donghai ZHENG Key laboratory of Cryospheric Science and Frozen soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Water sciences Beijing Normal UniversityBeijing 100038China School of Water and Environment Chang’an UniversityXi’an 710064China College of Hydrology and Water resources Hohai UniversityNanjing 210098China State Key laboratory of soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Department of Civil and Environmental Engineering Pennsylvania State UniversityState CollegePA 16801USA Department of earth and Environmental Science School of Human Settlements and Civil EngineeringXi’an Jiaotong UniversityXi’an 710049China Institute of Tibetan Plateau research Chinese Academy of SciencesBeijing 100101China

Hydrological modeling,leveraging mathematical formulations to represent the hydrological cycle,is a pivotal tool in representing the spatiotemporal dynamics and distribution patterns inherent in *** models serve a dual purpose:they validate theoretical robustness and applicability via observational data and project future trends,thereby bridging the understanding and prediction of natural *** rapid advancements in computational methodologies and the continuous evolution of observational and experimental techniques,the development of numerical hydrological models based on physicallybased surface-subsurface process coupling have *** in micro-scale conservation principles and physical equations,these models employ numerical techniques to integrate surface and subsurface hydrodynamics,thus replicating the macro-scale hydrological responses of *** hydrological models have emerged as a leading and predominant trend in hydrological modeling due to their explicit representation of physical processes,heightened by their spatiotemporal resolution and reliance on interdisciplinary *** article focuses on the theoretical foundation of surface-subsurface numerical hydrological *** includes a comparative and analytical discussion of leading numerical hydrological models,encompassing model architecture,numerical solution strategies,spatial representation,and coupling ***,this paper contrasts these models with traditional hydrological models,thereby delineating the relative merits,drawbacks,and future directions of numerical hydrological modeling.

关键词： Numerical Hydrological Models Surface-Subsurface Process Coupling Numerical Methods Hydrological Modeling

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Spatial heterogeneity and compositional profiles of dissolved organic matter in farmland soils across China' Mainland

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Journal of Environmental sciences 2024年第3期137卷 593-603页

作者： Bingjun Han Liyuan Chen Kang Xiao Yang Liu Dong Cao Lu Yu Yujun Li Shu Tao Wenxin Liu Key laboratory for earth Surface Processes College of Urban and Environmental SciencesPeking UniversityBeijing 100871China Beijing Yanshan earth Critical Zone National research Station College of Resources and EnvironmentUniversity of Chinese Academy of SciencesBeijing 101408China Center for Water and Ecology State Key Joint Laboratory of Environment Simulation and Pollution ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China State Key laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental ScienceChinese Academy of SciencesBeijing 100085China

Dissolved organic matter(DOM) plays an essential role in many geochemical processes,however its complexity, chemical diversity, and molecular composition are poorly understood. soil samples were collected from 500 vegetable fields in administrative regions of China' Mainland, of which 122 were selected for further investigation. DOM properties were characterized by three-dimensional excitation-emission matrix(3D-EEM) fuorescence spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry(FTICRMS)(field intensity is 15 Tesla). Our results indicated that the main constituents were UVA humic-like substances, humic-like substances, fulvic acid-like substances, and tyrosine-like substances. A total of 10,989 molecular formulae with a mass range of 100.04 to 799.59 Da were detected, covering the mass spectrometric information of the soil samples from 27 different regions. CHO and CHON molecules were dominant in DOM, whereas lignin, tannins,and aromatic substances served as the main components. The results of cluster analysis revealed that the soil properties in Jiangxi Province were considerably different from those in other regions. The key backgrounds of the DOM molecular characteristics in the vegetablefield soil samples across China' Mainland were provided at the molecular level, with large abundance and great variability.

关键词： Dissolved organic matter(DOM) Fourier transform ion cyclotron resonance mass(FTICR-MS) Excitation-emission matrix(EEM) Vegetable-field soils China' Mainland

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Identification of carbonates with high positive carbon isotope excursion from the Liaohe Group in the northeastern North China Craton and implications for the Lomagundi-Jatuli Event

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Science China earth sciences 2024年第9期67卷 2824-2844页

作者： Hongyu WANG Shuanhong ZHANG Sen WANG Linghao KONG Yue ZHAO Qiqi ZHANG Sen GAO Guohui HU Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China Key laboratory of Paleomagnetism and Tectonic Reconstruction Ministry of Natural ResourcesBeijing 100081China SinoProbe laboratory Chinese Academy of Geological SciencesBeijing 100037China School of earth Science and Mineral resources China University of GeosciencesBeijing 100083China

The Great Oxidation Event(GOE)during the early Paleoproterozoic represents the first significant buildup in earth’s atmospheric oxygen and resulted in a series of significant changes in the earth’s surface *** them is the 2.22(or 2.33)–2.06 Ga Lomagundi-Jatuli Event(LJE),which is globally,the largest magnitude and longest duration,marine carbonate positive carbon isotope excursion(δ^(13)C_(V-PDB)>10‰)*** event has attracted the attention of scholars all over the ***,except for a high positive carbon isotope excursion(δ^(13)C_(V-PDB)>10‰)recently identified from marine carbonate rocks within the Daposhan Formation in the lower Fanhe Group(or the Sanchazi Group)in the Longgang Block in the northeast North China Craton(NCC),Paleoproterozoic carbonates in the NCC are characterized by a low-amplitude positive carbon isotope excursion(δ^(13)C_(V-PDB)10‰)of marine carbonate rocks occurred at about 2.15 *** co

关键词： Lomagundi-Jatuli Event(LJE) Great Oxidation Event(GOE) Carbon-oxygen isotopes Liaohe Group Marine carbonate Jiao-Liao-Ji Belt North China Craton

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Disastrous effects of climate change on High Mountain Asia

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Advances in Climate Change research 2024年第3期15卷 365-366页

作者： Peng CUI Yao-Ming MA Yan WANG Bin-BinWANG Institute of Geographic sciences and Natural resources research The Chinese Academy of Sciences(CAS)Beijing 100101China Institute of Mountain Hazards and Environment CASChengdu 610041China China-Pakistan Joint research Center on earth sciences CAS-HECIslamabad 45320Pakistan State Key laboratory of Tibetan Plateau earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchCASBeijing 100101China

High Mountain Asia(HMA),encompassing the Tibetan Plateau and the surrounding high mountain ranges of the Hindu Kush and Tianshan,is a region characterised by large terrain,complex topography and the interplay of vario... 详细信息

关键词： terrain Tianshan Tibetan

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Source Enrichment Control on the Scale of Magmatic-Hydrothermal W-Sn Mineralization:Insights from Triassic and Jurassic Magma Reservoirs in the Continental Crust,Xitian,South China

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 132-149页

作者： GUO Chunli Simon AWILDE Coralie SIEGEL CHEN Zhenyu WU Shichong MNR Key laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China SinoProbe laboratory Chinese Academy of Geological SciencesBeijing 100094China School of earth and Planetary sciences Curtin UniversityPerth 6845Australia Discovery Program Mineral ResourcesCommonwealth Scientific and Industrial Research OrganisationAustralian Resources Research CentrePerth 6151Australia No.416 Geological Group Hunan Bureau of Mineral Exploration and DevelopmentZhuzhouHunan 412007China

There are two factors,source composition and magmatic differentiation,potentially controlling W-Sn *** one is more important is widely debated and may need to be determined for each individual *** Xitian granite batholith located in South China is a natural laboratory for investigating the above *** consists essentially of two separate components,formed in the Triassic at ca.226 Ma and Jurassic at ca.152 Ma,*** Triassic and Jurassic rocks are both composed of porphyritic and fine-grained *** latter resulted from highlydifferentiated porphyritic ones but they have similar textural characteristics and mineral assemblages,indicating that they reached a similar degree of crystal *** both fine-grained phases are highly differentiated with elevated rare metal contents,economic W–Sn mineralization is rare in the Triassic granitoids and this can be attributed to less fertile source materials than their Jurassic counterparts,with a slightly more enriched isotopic signature and whole-rockεNd(226 Ma)of−10.4 to−9.2(2σ=0.2)compared withεNd(152 Ma)of−9.2 to−8.2(2σ=0.2)for the Jurassic *** initial W-Sn enrichment was derived from the metasedimentary rocks and strongly enhanced by reworking of the continental crust,culminating in the Jurassic.

关键词： W-Sn mineralization magma reservoir geometry crystal fractionation Xitian Triassic-Jurassic granitic batholith Nanling Range South China

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Understanding the mechanisms and potential pathways of soil carbon sequestration from the biogeochemistry perspective

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Science China earth sciences 2024年第11期67卷 3386-3396页

作者： Xiaojuan FENG Guohua DAI Ting LIU Juan JIA Erxiong ZHU Chengzhu LIU Yunpeng ZHAO Ya WANG Enze KANG Jun XIAO Wei LI State Key laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences China National Botanical Garden College of resources and Environment University of Chinese Academy of Sciences Department of earth sciences National Natural Science Foundation of China

soil carbon sequestration is listed by the united Nations Framework Convention on Climate Change as one of the key ways to achieve long-term “carbon neutrality” in the context of global warming. soil carbon sequestration is a complex biogeochemical process that involves plants, microbes, and rock minerals at its core. Yet, its regulation mechanisms and promotion pathways remain unclear. This paper reviews recent progress in the related domestic and international research and provides an overview of the key processes and mechanisms of soil carbon sequestration. The main pathways for enhancing soil carbon sequestration(including plant inputs, mineral protection, microbial transformation, and rock weathering) are summarized. The paper also discusses and synthesizes how advanced biogeochemical methods and technologies may be employed to explore soil carbon sequestration mechanisms and potentials. The overall aim of this review is to improve our understanding of soil carbon sequestration as a nature-based solution to combatting climate change from the biogeochemistry perspective, and to highlight the role of fundamental research in earth sciences in helping to achieve China's carbon neutrality goals.

关键词： Carbon neutrality Plant input Microbial carbon pump Mineral protection Rock weathering

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