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Texture and Geochemistry of Multi-stage Hydrothermal Scheelite in the Mamupu Cu-Au-Mo(-W)Deposit,Eastern Tibet:Implications for Tungsten Mineralization in the Yulong Belt

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 701-716页

作者： ZHANG Xiaoxu TANG Juxing LIN Bin WANG Qin HE Liang YAN Gang SHAO Rui WU Qiang DU Qiu ZHAXI Pingcuo Chengdu Center China Geological Survey(Geosciences Innovation Center of Southwest China)Chengdu 610081China 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 Earth Sciences College Chengdu University of TechnologyChengdu 610059China No.6 geological Party Tibetan Bureau of Geology and Mineral Exploration and DevelopmentLhasa 851400China Tibet Shengyuan Mining Group Co. Ltd.Lhasa 851400China

Multistage tungsten mineralization was recently discovered in the Mamupu copper-polymetallic deposit in the southern Yulong porphyry copper belt(YPCB),*** study reports the results of cathodoluminescence,trace element and Sr isotope analyses of Mamupu scheelite samples,undertaken in order to better constrain the mechanism of W mineralization and the sources of the ore-forming *** different types of scheelite are identified in the Mamupu deposit:scheelite A(Sch A)mainly occurs in breccias during the prograde stage,scheelite B(Sch B)forms in the chlorite-epidote alteration zone in the retrograde stage,while scheelite C(Sch C)occurs in distal quartz sulfide *** extremely high Mo content and negative Eu anomaly in Sch A represent high oxygen fugacity in the prograde *** with ore-related porphyries,Sch A has a similar REE pattern,but with higher ΣREE,more depleted HREE and slightly lower(^(87)Sr/^(86)Sr)i *** features suggest that Sch A is genetically related to ore-related porphyries,but extensive interaction with carbonate surrounding rocks affects the final REE and Sr isotopic *** B shows dark(Sch B-I)and light(Sch B-II)domains under CL *** Sch B-I to Sch B-II,LREEs are gradually depleted,with MREEs being gradually *** C has the highest LREE/HREE ratio,which indicates that it inherited the geochemical characteristics of fluids after the precipitation of HREE-rich minerals,such as diopside and garnet,in the early prograde *** Mo content in Sch B and Sch C gradually decreased,indicating that the oxygen fugacity of the fluids changed from oxidative in the early stages to reductive in the later,the turbulent Eu anomaly in Sch B and Sch C indicating that the Eu anomaly in the Mamupu scheelite is not solely controlled by oxygen *** extensive interaction of magmatic-hydrothermal fluids and carbonate provides the necessary Ca^(2+)for the precipitation of scheelite in the Mamupu deposit.

关键词： scheelite geochemistry Mamupu Cu deposit Yulong porphyry copper belt eastern Tibet

Jet Characteristics and Optimization of a Cavitation Nozzle for Hydraulic Fracturing Applications

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Fluid Dynamics & Materials Processing 2024年第1期20卷 179-192页

作者： Yu Gao Zhenqiang Xu Kaixiang Shen Shenzhen South China Sea Oil Economic Development Co. Ltd.Shenzhen518000China Guangzhou Marine geological Survey China Geological SurveyGuangzhou511458China National Engineering Research Center of Gas Hydrate Exploration and Development Guangzhou511458China

Hydraulic jetting is a form of fracturing that involves using a high-pressure jet of water to create fractures in the reservoir rock with a nozzle serving as the central component of the hydraulic sandblasting perforation *** this study,the flow behavior of the nozzle is simulated numerically in the framework of a SST k-ωturbulence *** results show that the nozzle structure can significantly influence the jet performance and related cavitation *** orthogonal experiments,the nozzle geometric parameters are optimized,and the following configuration is found accordingly:contraction angle 20°,contraction segment length 6 mm,cylindrical segment diameter 6 mm,cylindrical segment length 12 mm,spread segment length 10 mm,and spread angle 55°.

关键词： Cavitation jet angle nozzle hydraulic characteristics nozzle parameters

Plume-lithosphere interaction in the Comei Large Igneous Province: Evidence from two types of mafic dykes in Gyangze, south Tibet, China

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China Geology 2024年第1期7卷 80-90页

作者： Ya-ying Wang Ling-sen Zeng Li-e Gao Li-long Yan Ling-hao Zhao Jia-hao Gao Ying-long Di Guang-xu Li Yi-hong Tian Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China National Research Center for Geoanalysis Chinese Academy of Geological SciencesBeijing 100037China China Nonferrous Metals(Guilin)Geology and Mining Co. LtdGuilin 541004China

Two suites of mafic dykes,T1193-A and T1194-A,outcrop in Gyangze area,southeast *** are in the area of Comei LIP and have indistinguishable field occurrences with two other dykes in Gyangze,T0902 dyke with 137.7±1.3 Ma zircon age and T0907 dyke with 142±1.4 Ma zircon age reported by Wang YY et al.(2016),indicating coeval formation *** all the four diabase dykes into consideration,two different types,OIB-type and weak enriched-type,can be ***“OIB-type”samples,including T1193-A and T0907 dykes,show OIB-like geochemical features and have initial Sr-Nd isotopic values similar with most mafic products in Comei Large Igneous Provinces(LIP),suggesting that they represent melts directly generated from the Kerguelen mantle ***“weak enriched-type”samples,including T1194-A and T0902 dykes,have REEs and trace element patterns showing withinplate affinity but have obvious Nb-Ta-Ti negative *** show uniform lowerεNd(t)values(−6‒−2)and higher 87Sr/86Sr(t)values(0.706‒0.709)independent of their MgO variation,indicating one enriched mantle *** their closely spatial and temporal relationship with the widespread Comei LIP magmatic products in Tethyan Himalaya,these“weak enriched-type”samples are consistent with mixing of melts from mantle plume and the above ancient Tethyan Himalaya subcontinental lithospheric mantle(SCLM)in different *** weak enriched mafic rocks in Comei LIP form one special rock group and most likely suggest large scale hot mantle plume-continental lithosphere *** process may lead to strong modification of the Tethyan Himalaya lithosphere in the Early Cretaceous.

关键词： OIB type diabase Comei Large Igneous Province Weakly enriched diabase Plume-lithosphere interaction Nb-Ta-Ti negative anomaly Kerguelen plume geological survey engineering Tibet Plateau

A New Discovery of Mineralization as Subseafloor Hydrothermal Replacement in the Duddar Super-Large SEDEX Lead-Zinc Deposit in Pakistan

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Journal of Earth Science 2024年第3期35卷 1075-1078页

作者： Huishan Zhang Yucai Song Jianing Sun Jun Hong Yasir Shaheen Khalil Yanguang Li Haidi Zhang Zhihua Wang MNR Key Laboratory for the Study of Focused Magmatism and Giant Ore Deposits Xi’an Center of Geological SurveyChina Geological SurveyXi’an 710054China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Chengdu Center of geological Survey China Geological SurveyChengdu 610081China China Huaye Group Co. LtdBeijing 100037China geological Survey of Pakistan Islamabad 44000Pakistan

0 INTRODUCTION Sedimentary exhalative(SEDEX)lead-zinc deposit was traditionally considered as a result of submarine hydrothermal exhalation,including exhalative plume and brine pool models(Izanloo et al.,2022;Spinks et al.,2021;Maghfouri et al.,2020;Sangster,2020,2018;Huang et al.,2019;Rajabi et al.,2015;Goodfellow and Lydon,2007;Large et al.,2005,2001;Peng et al.,2000;Goodfellow et al.,1993;Figures 1a,1b).However,recognition of mineralization as subseafloor hydrothermal replacement in a few SEDEX deposits has challenged the traditional consideration(Magnall et al.,2023,2021,2020a,b;Hayward et al.,2021;Figure 1c).Researchers come to believe that subseafloor replacement rather than submarine exhalation is a dominant process for SEDEX mineralization,but this needs to be examined through more case studies.

关键词： submarine mineralization seafloor

geological conditions and reservoir characteristics of various shales in major shalehosted regions of China

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China Geology 2024年第1期7卷 138-149页

作者： Shu-jing Bao Tian-xu Guo Jin-tao Yin Wei-bin Liu Sheng-jian Wang Hao-han Li Zhi Zhou Shi-zhen Li Xiang-lin Chen The Key Laboratory of Unconventional Petroleum Geology China Geological SurveyMinistry of Natural Resources100083 BeijingChina Oil and Gas Survey China Geological Survey100083 BeijingChina Research Institute of Yanchang Petroleum(Group)CO.ltd 710076 Xi’anChina

China is home to shales of three facies:Marine shale,continental shale,and marine-continental transitional *** types of shale gas are associated with significantly different formation conditions and major controlling *** study compared the geological characteristics of various shales and analyzed the influences of different parameters on the formation and accumulation of shale *** general,shales in China’s several regions exhibit high total organic carbon(TOC)contents,which lays a sound material basis for shale gas *** strata generally show high degrees of thermal *** contrast,continental shales manifest low degrees of thermal evolution,necessitating focusing on areas with relatively high degrees of thermal evolution in the process of shale gas surveys for these *** shales of the Wufeng and Silurian formations constitute the most favorable shale gas reservoirs since they exhibit the highest porosity among the three types of *** shales are followed by those in the Niutitang and Longtan *** contrast,the shales of the Doushantuo,Yanchang,and Qingshankou formations manifest low ***,the shales of the Wufeng and Longmaxi formations exhibit high brittle mineral *** a low siliceous mineral content,the shales of the Doushantuo Formation feature a high carbonate mineral content,which can increase the shales’brittleness to some *** marine-continental transitional shales,where thin interbeds of tight sandstone with unequal thicknesses are generally found,it is recommended that fracturing combined with drainage of multiple sets of lithologic strata should be employed to enhance their shale gas production.

关键词： Shale gas Marine shale Continental shale Marine-continental transitional shale Neoproterozoic-Cretaceous strata geological conditions Reservoir characteristics Petroleum geological survey engineering

Three-dimensional Modeling of Ore-forming Elements and Mineralization Prognosis for the Yechangping Mo Deposit,Henan Province,China

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 736-752页

作者： DING Gaoming JI Genyuan YAN Guolong XU Yongzhong WANG Kunming XIAO Chun WANG Quanle GUO Dongbao China National Administration of Coal Geology Beijing 100038China MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesCAGSBeijing 100037China China Gold Group geological Co. Ltd.Beijing 100011China China Gold Group ZhongYuan Mining Co. Ltd.SanmenxiaHenan 472000China Lanzhou Mineral Exploration Institute of Gansu Nonferrous Metal geological Exploration Bureau Lanzhou 730046China

Three-dimensional geochemical modeling of ore-forming elements is crucial for predicting deep *** approach provides key information for the quantitative prediction of deep mineral localization,three-dimensional fine interpolation,analysis of spatial distribution patterns,and extraction of quantitative mineral-seeking *** Yechangping molybdenum(Mo)deposit is a significant and extensive porphyry-skarn deposit in the East Qinling-Dabie Mo polymetallic metallogenic belt at the southern margin of the North China *** borehole data on oreforming elements underpin deep geochemical *** methodology includes the following steps:(1)Threedimensional geological modeling of the deposit was established.(2)Correlation,cluster,and factor analyses post delineation of mineralization stages and determination of mineral generation sequence to identify(Cu,Pb,Zn,Ag)and(Mo,W,mfe)assemblages.(3)A three-dimensional geochemical block model was constructed for Mo,W,mfe,Cu,Zn,Pb,and Ag using the ordinary kriging method,and the variational function was developed.(4)Spatial distribution and enrichment characteristics analysis of ore-forming elements are performed to extract geological information,employing the variogram and w(Cu+Pb+Zn+Ag)/w(Mo+W)as predictive indicators.(5)Identifying the western,northwestern,and southwestern areas of the mine with limited mineralization potential,contrasted by the northeastern and southeastern areas favorable for mineral exploration.

关键词： 3D geochemical model ore-forming elements geostatistics deep mineralization prediction Yechangping Mo deposit

Comparative study of different machine learning models in landslide susceptibility assessment: A case study of Conghua District, Guangzhou, China

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China Geology 2024年第1期7卷 104-115页

作者： Ao Zhang Xin-wen Zhao Xing-yuezi Zhao Xiao-zhan Zheng Min Zeng Xuan Huang Pan Wu Tuo Jiang Shi-chang Wang Jun He Yi-yong Li Wuhan Center China Geological SurveyMinistry of Natural Resources(Geosciences Innovation Center of Central South China)Wuhan 430205China Guangzhou Institute of geological Survey Guangzhou 510080China Hubei Transportation Planning Design Institute Co. LtdWuhan 430050China

Machine learning is currently one of the research hotspots in the field of landslide *** clarify and evaluate the differences in characteristics and prediction effects of different machine learning models,Conghua District,which is the most prone to landslide disasters in Guangzhou,was selected for landslide susceptibility *** evaluation factors were selected by using correlation analysis and variance expansion factor *** four machine learning methods namely Logistic Regression(LR),Random Forest(RF),Support Vector Machines(SVM),and Extreme Gradient Boosting(XGB),landslide models were *** analysis and evaluation of the model were conducted through statistical indices and receiver operating characteristic(ROC)*** results showed that LR,RF,SVM,and XGB models have good predictive performance for landslide susceptibility,with the area under curve(AUC)values of 0.752,0.965,0.996,and 0.998,*** model had the highest predictive ability,followed by RF model,SVM model,and LR *** frequency ratio(FR)accuracy of LR,RF,SVM,and XGB models was 0.775,0.842,0.759,and 0.822,*** and XGB models were superior to LR and SVM models,indicating that the integrated algorithm has better predictive ability than a single classification algorithm in regional landslide classification problems.

关键词： Landslides susceptibility assessment Machine learning Logistic Regression Random Forest Support Vector Machines XGBoost Assessment model geological disaster investigation and prevention engineering

Airblast evolution initiated by Wangjiayan landslides in the M_(s)8.0 Wenchuan earthquake and its destructive capacity analysis

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China Geology 2024年第2期7卷 237-247页

作者： Yu-feng Wang Qian-gong Cheng Qi Zhu Department of geological Engineering Southwest Jiaotong UniversityChengdu 610031China Sichuan Highway Planning SurveyDesign and Research Institute LtdChengdu 610041China

Airblasts,as one common phenomenon accompanied by rapid movements of landslides or rock/snow avalanches,commonly result in catastrophic damages and are attracting more and more scientific *** quantitatively analyze the intensity of airblast initiated by landslides,the Wangjiayan landslide,occurred in the Wenchuan earthquake,is selected here with the landslide propagation and airblast evolution being studied using FLUENT by introducing the Voellmy rheological *** results reveal that:(1)For the Wangjiayan landslide,its whole travelling duration is only 12 s with its maximum velocity reaching 36 m/s at t=10 s;(2)corresponding to the landslide propagation,the maximum velocity,28 m/s,of the airblast initiated by the landslide also appears at t=10 s with its maximum pressure reaching594.8 Pa,which is equivalent to violent storm;(3)under the attack of airblast,the load suffered by buildings in the airblast zone increases to 1300 Pa at t=9.4 s and sharply decreased to-7000 Pa as the rapid decrease of the velocity of the sliding mass at t=10 s,which is seriously unfavorable for buildings and might be the key reason for the destructive collapse of buildings in the airblast zone of the Wangjiayan landslide.

关键词： Landslide Voellmy rheological law 3D FLUENT simulation Airblast Intensity Building destructive collapse Wenchuan earthquake geological hazards survey engineering

Spatial structural characteristics of the Deda ancient landslide in the eastern Tibetan Plateau:Insights from Audio-frequency Magnetotellurics and the Microtremor Survey Method

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China Geology 2024年第2期7卷 188-202页

作者： Zhen-dong Qiu Chang-bao Guo Yi-ying Zhang Zhi-hua Yang Rui-an Wu Yi-qiu Yan Wen-kai Chen Feng Jin Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China Faculty of Engineering China University of GeosciencesWuhan 430074China Key Laboratory of Active Tectonics and geological Safety Ministry of Natural ResourcesBeijing 100081China Research Center of Neotectonism and Crustal Stability China Geological SurveyBeijing 100081China China Water Resources Beifang Investigation Design and Research Co.Ltd.Tianjin 300222China

It is of crucial importance to investigate the spatial structures of ancient landslides in the eastern Tibetan Plateau’s alpine canyons as they could provide valuable insights into the evolutionary history of the landslides and indicate the potential for future *** study examines the Deda ancient landslide,situated in the Chalong-ranbu fault zone,where creep deformation suggests a complex underground *** integrating remote sensing,field surveys,Audio-frequency Magnetotellurics(AMT),and Microtremor Survey Method(MSM)techniques,along with engineering geological drilling for validation,to uncover the landslide’s spatial feature *** research indicates that a fault is developed in the upper part of the Deda ancient landslide,and the gully divides it into Deda landslide accumulation zoneⅠand Deda landslide accumulation zoneⅡin *** distinctive geological characteristics detectable by MSM in the shallow subsurface and by AMT in deeper *** findings include the identification of two sliding zones in the Deda I landslide,the shallow sliding zone(DD-I-S1)depth is approximately 20 m,and the deep sliding zone(DD-I-S2)depth is 36.2-49.9 *** sliding zone(DD-Ⅱ-S1)depth of the DedaⅡlandslide is 37.6-43.1 m.A novel MSM-based method for sliding zone identification is proposed,achieving less than 5%discrepancy in depth determination when compared with drilling *** results provide a valuable reference for the spatial structural analysis of large-deepseated landslides in geologically complex regions like the eastern Tibetan Plateau.

关键词： Ancient landslide Remote sensing Audio-frequency Magnetotellurics(AMT) Microtremor Survey Method(MSM) geological drilling engineering Spatial structure Tibetan Plateau geological hazard survey engineering