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Journal of Geographic Information System 2024年第4期16卷 244-258页

作者： Sadia Mazahir Akram Javed Mohd Yusuf Khanday Department of Geology Aligarh Muslim University Aligarh India geological survey of India Western Region Jaipur India

Land cover is an impression of natural cover on surface of earth such as bare soil, river, grass etc. and utilization of these natural covers for various human needs and purposes by mankind is defined as land use. Land cover identification, delineation and mapping is important for planning activities, resource management and global monitoring studies while baseline mapping and subsequent monitoring is done by application of land use to get timely information about quantity of land that has been used. The present study has been carried out in Dhund river watershed of Jaipur, Rajasthan which covers an area of about 1828 sq∙km. The minimum and maximum elevation of the area is found to be 214 m and 603 m respectively. Land use and land cover changes of three decades from 1991 to 2021 have been interpreted by using remotes sensing and GIS techniques. ArcGIS software (Arc map 10.2), SOI topographic map, Cartosat-1 DEM and satellite data of Landsat 5 and Landsat 8 have been used for interpretation of eleven classes. The study shows an increase in cultivated land, settlement, waterbody, open forest, plantation and mining due to urbanization because of increasing demands of food, shelter and water while a decrease in dense forest, river, open scrub, wasteland and uncultivated land has also been marked due to destruction of aforementioned by anthropogenic activities such as industrialization resulting in environmental degradation that leads to air, soil and water pollution.

关键词： Dhund River Landsat Land Use/Land Cover Change Detection Analysis Rajasthan

Research on the Application of Electromagnetic Method in the Exploration of Altered Rock-type Gold Deposits in the East Kunlun Metallogenic Belt

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Acta Geologica Sinica(English Edition) 2024年第S1期 18-21页

作者： DONG Ji'en ZHANG Huiqing WANG Peng LI Hua YE Gaofeng YU Xiaoliang LI Jie Qinghai geological survey MNR Technology Innovation Center for Exploration and Exploitation of Strategic Mineral Resources in Plateau Desert Region School of Geophysics and Information Technology China University of Geosciences

Introduction The East Kunlun Orogenic Belt is located in the northeastern part of the Qinghai–Tibet Plateau(Li et al., 2007), stretching from the East Kunlun to the Elashan area in an east–west direction(Guo et al., 2018). It is an important part of the Central Orogenic Belt(Xiong et al., 2023). It is considered one of the important gold mineralization regions in the Tethys tectonic domain(Norbu et al., 2023) and an essential potential base for mineral resources in China. Wulonggou and Gouli gold mines have been discovered successively, earning the reputation of the "Golden Belt of Qinghai Province"(Feng et al., 2004; He et al., 2023).

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Genetic Analysis of Structural Styles in the Makran Accretionary Wedge–Insight from Physical Simulations

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Journal of Ocean University of China 2024年第1期23卷 157-172页

作者： SHAO Longfei YU Fusheng GONG Jianming LIAO Jing YU Zhifeng TANG Liang CHEN Jiangong WANG Yuefeng NENG Yuan School of Earth Sciences China University of PetroleumBeijing 102249China State Key Laboratory of Petroleum Resources and Processing China University of PetroleumBeijing 102249China Qingdao Institute of Marine Geology China Geological SurveyQingdao 266071China China University of Petroleum–Beijing at Karamay Karamay 834000China

The Makran accretionary wedge has the smallest subduction angle among any accretionary prism in the world. The factors controlling the spacing and morphological development of its deep thrust faults, as well as the formation mechanism of shallow normal faults, remain unclear. Meanwhile, the factors affecting the continuity of plane faults must be comprehensively discussed. Clarifying the development characteristics and deformation mechanisms of the Makran accretionary wedge is crucial to effectively guide the exploration of gas hydrate deposits in the area. This study aims to interpret seismic data to identify typical structures in the Makran accretionary wedge, including deep imbricate thrust faults, shallow and small normal faults, wedge-shaped piggyback basins, mud diapirs with fuzzy and disorderly characteristics of reflection, décollements with a northward tilt of 1° – 2°, and large seamounts. Physical simulation-based experiments are performed to comprehensively analyze the results of the plane, section, and slices of the wedge. Results reveal that the distances between and shapes of thrust faults in the deep parts of the Makran accretionary wedge are controlled by the bottom décollement. The uplift of the thrust fault-related folds and the upwelling of the mud diapirs primarily contribute to the formation of small normal faults in the shallow part of the area. The mud diapirs originate from plastic material at the bottom, while those that have developed in the area near the trench are larger. Seamounts and mud diapirs break the continuity of fault plane distribution.

关键词： Makran accretionary wedge structural styles faults distribution physical simulation

A typical paleochannel-controlled ground fissure in Hengshui， Hebei Plain， China

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Journal of Earth Science 2024年

作者： Feiyong Wang Jianbing Peng Jishan Xu Quanzhong Lu School of Geology Engineering and Geomatics， Chang'an University Key Laboratory of Western China's Mineral Resources and geological Engineering， Ministry of Education， Chang'an University Key Laboratory of Earth Fissures geological Disaster， Ministry of Natural Resources (geological survey of Jiangsu Province) School of Engineering and Technology， Institute of Geosafety， China University of Geosciences， Beijing School of Resources and Geosciences， China University of Mining and Technology

Nearly 1 100 fissures have formed on the Hebei Plain in China. Within the Yellow River-Qinghe River-Zhanghe River shallow buried paleochannel Band on the plain， 93 ground fissures controlled by paleochannels have developed. Among them， The Wuyi-Fuping ground fissure is a typical paleochannel-controlled fissure located in Hengshui， Hebei Province， with a total length of 3 km， a dominant strike of NE78°， and nearly upright in the shallow layer. The surface damage observed in this fissure primarily manifests as beaded pits， and its activity showcases distinct segmentation characteristics. On the trench profiles， the offset distance of shallow layers remains consistently around 20 cm within the depth range of 0 m to -3 m. An evident flexure is observed in the strata at depths ranging from -4.5 to -7 m. The drilling profile reveals that there is an absence of dislocations in the deeper strata. Nonetheless， the shallow seismic physical profiles unveil the presence of underlying faults beneath the study area， underscoring the intricate formation process and genesis mechanism of the Wuyi-Fuping ground fissure. Firstly， the formation and evolution of the Qingling River’s paleochannel were shaped by the actions of fault blocks and underlying faults. The interplay of the regional stress field， fault block movement， and fault activity played pivotal roles in driving the development of this paleochannel. Secondly， the paleochannel exerts a controlling influence on the development location and severity of the fissure. During pumping， the confined aquifer within the paleochannel undergoes water loss and compression， resulting in the formation of a surface subsidence funnel. When the tensile stress surpasses the soil’s tensile strength at the funnel’s edge， the soil fractures， giving rise to a ground fissure. Finally， large amounts of surface water generated by heavy rainfall and irrigation can cause existing hidden ground fissures to rupture， emerge， and expand. This paper provide

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Discovery and characterization of a new hydrothermal field at 2°N on the slow-spreading Carlsberg Ridge

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Journal of Oceanology and Limnology 2024年第4期42卷 1106-1118页

作者： Zhongyan QIU Yejian WANG Xiqiu HAN Honglin LI Xing YU Ruyong CUI Mou LI Xuegang CHEN Jiqiang LIU Key Laboratory of Submarine Geosciences&Second Institute of Oceanography Ministry of Natural ResourcesHangzhou 310012China Qingdao Institute of Marine Geology China Geological SurveyQingdao 266071China School of Earth Science Zhejiang UniversityHangzhou 310027China Ocean College Zhejiang UniversityZhoushan 316021China

A new hydrothermal field(Tianshi)was discovered on the rift valley wall through plume anomaly surveys and geological work conducted in 2012 and 2018 between 2°35′N and 2°43′N of the slow-spreading Carlsberg Ridge(CR).Here,the results of two expeditions conducted to detect and characterize the new hydrothermal field are *** and geochemical data,as well as 14 C ages of a sediment core collected near the field are presented to reveal the hydrothermal *** show that the Tianshi field is a basalt-hosted hydrothermal *** data of the sediments collected near the field indicate a strong hydrothermal contribution,and hydrothermal Fe and Cu fluxes range from 30 to 155 mg/(cm^(2)·ka)and 0.59 to 11.49 mg/(cm^(2)·ka),*** variations in the fluxes of hydrothermal Fe indicate that there have been at least three amplified hydrothermal venting events(H 1,H 2,and H 3)in the Tianshi field over the last 35.2 ka,in 28.6-35.2 ka BP,22.0-27.6 ka BP,and 1.2-11.4 ka BP,*** event H 2 was driven by an increased magmatic production associated with sea level fall during the Last Glacial Maximum,while event H 3 was promoted by tectonic activity associated with a rapid sea level *** study further verified the role of sea level change in modulating hydrothermal activity on mid-ocean ridges.

关键词： plume anomaly sediment core new hydrothermal field hydrothermal history Carlsberg Ridge

Late Triassic Intracontinental Deformation of South Tianshan,Central Asia:Evidence from Syn-tectonic Sedimentation and Detrital Zircon Provenances of the Kuqa Depression

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 548-568页

作者： QIN Xiang CHEN Xuanhua SHAO Zhaogang ZHANG Yiping WANG Yongchao LI Bing SU He WANG Ye LIU Kui HAN Lele China Aero Geophysical survey and Remote Sensing Center for Natural Resources Beijing 100083China Key Laboratory of Airborne Geophysics and Remote Sensing Geology MNRBeijing 100083China Chinese Academy of geological Sciences Beijing 100037China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China

The Tianshan range,a Paleozoic orogenic belt in Central Asia,has undergone multiple phases of tectonic activities characterized by the N-S compression after the early Mesozoic,including the far-field effects of the Cenozoic Indian-Asian ***,there are limited reports on the tectonic deformation and initiation of Triassic intracontinental deformation in the Tianshan *** this structural context is crucial for interpreting the early intracontinental deformation history of the Eurasian continent during the early *** strata and syn-tectonic sediments provide a rich source of information on tectonic activities and have been extensively used in the studies of orogenic *** on detail fieldwork conducted in this study,the middle-late Triassic Kelamayi Formation of the northern Kuqa Depression in the southern Tianshan fold-thrust belt has been identified as the typical syn-tectonic growth *** youngest detrital zircon component in two lithic sandstone samples from the bottom and top of the Kelamayi growth strata yielded U-Pb ages of 223.4±3.1 and 215.5±2.9 Ma,respectively,indicating that the maximum depositional age of the bottom and top of the Kelamayi growth strata is 226-220 and 218-212 *** geochronological distribution of detrital samples from the Early-Middle Triassic and Late Triassic revealed abrupt changes,suggesting a new source supply resulting from tectonic activation in the Tianshan *** coupling relationship between the syn-tectonic sedimentation of the Kelamayi Formation and the South Tianshan fold-thrust system provides robust evidence that the Triassic intracontinental deformation of the South Tianshan range began at approximately 226-220 Ma(during the Late Triassic)and ended at approximately 218-212 *** findings provide crucial constraints for understanding the intraplate deformation in the Tianshan range during the Triassic.

关键词： growth strata basin-mountain coupling Triassic Indosinian event Kuqa Depression South Tianshan

A potential giant gallium deposit hosted in the tailing dam of the Fankou Zn-Pb deposit in northern Guangdong Province, South China

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China Geology 2024年第1期7卷 157-160页

作者： Peng-peng Yu Zhao-bin Hu Yi Zheng Lan-xuan Guo Shi-yuan Ouyang Gui-qiang Yuan Shang-zhou Chen Cheng-ming Wang Xi Chen School of Earth Sciences and geological Engineering Sun Yat-sen UniversityGuangzhou 510275China Guangdong Provincial Key Lab of geological Process and Mineral Resources survey Sun Yat-sen UniversityGuangzhou 510275China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519000China Zhongjin Lingnan Nonfemet Co. LtdShenzhen 518000China

*** The Fankou giant zinc(Zn)-lead(Pb)deposit in Guangdong Province is well-known for its huge reserves of over 10 Mt(million ton)Zn+Pb metals and high ore-grade with Zn+Pb exceeding 15%(Guangdong Fankou Deposit Investigation Group,1980;Zhu XY et al.,2017).After 60 years of exploration and exploitation,the deposit has accumulated millions of tons of *** interesting question is that what components are hosted in these tailings,and whether some key and critical metals such as gallium and germanium are extremely enriched and worth further comprehensive *** motivated us to conduct an integrated set of field investigation,sampling,major-trace element analyses and reserve assessments about the Fankou *** this contribution,we discover that the tailings contain a variety of metal elements such as zinc,lead and gallium with comprehensive utilization *** data can act as a scientific guidance for further exploration and utilization of the Fankou tailings,and aid to enhance the utilization efficiency of the key mineral resource in *** study also provide demonstration for future green mine construction in China.

关键词： deposit comprehensive Guangdong

Geology and mineralization of the Dongping supergiant alkalic-hosted Au-Te deposit(>100 t Au)in Northern Hebei Province,China:A review

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China Geology 2024年第3期7卷 533-550页

作者： Shi-min Zhen Da-zhao Wang Zhong-jian Zha Hai-jun Bai Jiang Wang Development and Research Center of China geological survey Ministry of Natural ResourcesBeijing 100037China Technical Guidance Center for Mineral Resources Exploration Ministry of Natural ResourcesBeijing 100037China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China Institute of geological surveying and Mapping Technology of Anhui Province Hefei 230022China Third geological Brigade of Hebei Bureau of Geology and Mineral Resources Zhangjiakou 075000China Ulanqab Real Estate Registration Center Ulanqab 012099China

The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of *** paper presents a new understanding for Dongping ore system,based on the previous *** mineralization originally occurred at 400-380 Ma,simultaneous with emplacement of the Shuiquangou alkaline complex,and was overprinted by the hydrothermal activity in the *** compositions of ores indicate metals of the deposit are mainly provided by the Shuiquangou ***-forming fluids are characterized by increasing oxygen fugacity and decreasing sulfur fugacity,while tellurium fugacity increased in the Stage II-2 and decreased in Stage *** systematic changes are closely related to the processes of mineral precipitation and fluid *** precipitation from Stage Ⅰ to Stage Ⅱ was triggered by fluid boiling,which leads to the precipitation of Pb-Bi-Te,due to decrement of sulfur *** of gas phase containing high concentration of H_2Te leads to precipitation of Te-Au-Ag minerals and native *** on these hypotheses,this paper present a polyphase metallogenic model as *** the Devonian,fluids were released from alkaline magmas,which carried ore-forming materials form the surrounding rocks and precipitate the early *** the Jurassic-Cretaceous,fluorine-rich fluids exsolved from highly factionated Shangshuiquan granite,which extracted and concentrated Au from the Shuiquangou complex and the Sanggan Group metamorphic rocks,and finally formed the Dongping gold deposit.

关键词： Mineralization and alteration Alkaline intrusion Au deposit Physicochemical conditions Metallogenic model Oxygen fugacity Sulfur fugacity Mechanisms of mineral precipitation Fluid boiling Fluorine-enriched fluid Dongping gold deposit North China Craton Mineral exploration engineering

How do the landslide and non-landslide sampling strategies impact landslide susceptibility assessment? d A catchment-scale case study from China

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 877-894页

作者： Zizheng Guo Bixia Tian Yuhang Zhu Jun He Taili Zhang School of Civil and Transportation Engineering Hebei University of TechnologyTianjin300401China Hebei Key Laboratory of Earthquake Disaster Prevention and Risk Assessment Sanhe065201China Faculty of Engineering China University of GeosciencesWuhan430074China Nanjing Center China Geological SurveyMinistry of Natural ResourcesNanjing210016China

The aim of this study is to investigate the impacts of the sampling strategy of landslide and non-landslide on the performance of landslide susceptibility assessment(LSA).The study area is the Feiyun catchment in Wenzhou City,Southeast *** types of landslides samples,combined with seven non-landslide sampling strategies,resulted in a total of 14 *** corresponding landslide susceptibility map(LSM)for each scenario was generated using the random forest *** receiver operating characteristic(ROC)curve and statistical indicators were calculated and used to assess the impact of the dataset sampling *** results showed that higher accuracies were achieved when using the landslide core as positive samples,combined with non-landslide sampling from the very low zone or buffer *** results reveal the influence of landslide and non-landslide sampling strategies on the accuracy of LSA,which provides a reference for subsequent researchers aiming to obtain a more reasonable LSM.

关键词： Landslide susceptibility Sampling strategy Machine learning Random forest China

Origin and geological Significance of the Cambrian-Permian Mafic-felsic Magmatic Rocks in the Longshenggeng Area of the East Kunlun Orogenic Belt

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Journal of Earth Science 2024年

作者： Li Hua Su Huimin Tong Haikui Luo Changhai Zhang Jianxin Wang Tao Li Wenjun Xue Chaoping Dong Jiaxiang Che Yuying Chen Xiaolin Li Xiong Qinghai Provincial Bureau geological survey Bureau， MNR Technology Innovation Center for Exploration and Exploitation for Strategic Mineral Resources in Plateau Desert Region State Key Laboratory of geological Processes and Mineral Resources， Collaborative Innovation Center for Exploration of Strategic Mineral Resources， School of Earth Resources， China University of Geosciences Northwest Bureau of China Metallurgical Geology Bureau The Third geological Exploration Institute of Nonferrous Metals Xining

A set of ultramafic-mafic-felsic rock assemblages was discovered in the Longshenggeng area of the eastern part of the East Kunlun Orogenic Belt. Petrography， chronology and whole-rock geochemistry were conducted on this set of intrusive rock assemblages. U-Pb dating of apatite shows that the lherzolite formed at (492 ± 5) Ma， the granite at (473 ± 6) Ma， and the diabase at (260 ± 14) Ma， respectively. The lherzolites belong to a Supra-Subduction Zone type (SSZ-type) ophiolite component above a subduction zone; the granites formed in an ocean-continent subduction setting; and the diabases represent products of partial melting of an asthenospheric mantle at shallow depth. The East Kunlun Orogenic Belt features the East Kunzhong and Buqingshan-Animaqing ophiolitic melange belts， with the latter representing remnants of the Proto-Tethys Ocean. The late Cambrian lherzolites and granites in the Longshenggeng area were magmatic products of the back-arc ocean basin and island arc formed during the northward subduction of the Proto-Tethys Ocean. Subsequently， extensive island arc magmatism occurred from the late Permian to middle Triassic， driven by the northward subduction of the Paleo-Tethys Ocean beneath the East Kunlun Block. The diabase may have formed during the transition from subduction to post-collisional extension.

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