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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 {1. China Geological SurveyChengdu 610081China China Huaye Group Co. LtdBeijing 100037China geological {1. 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,2020,201.;Huang et al.,201.;Rajabi et al.,201.;Goodfellow and Lydon,2007;Large et al.,2005,2001.Peng et al.,2000;Goodfellow et al.,1.93;Figures 1.,1.).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 1.).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

The Middle and Late Holocene climate change in Bohai Bay revealed by diatom proxy

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Journal of Oceanology and Limnology 2024年第5期42卷 1493-1506页

作者： Zhiwen SHANG Jianfen LI Fu WANG Hong WANG Tianjin Centre China Geological SurveyTianjin 300170China Key Laboratory of Coastal Geo-environment China Geological SurveyTianjin 300170China Tianjin Key Laboratory of Coast geological Processes and Environmental Safety Tianjin 300170China

A total of 98 samples from two boreholes in shallow sea area and two oyster reefs in adjacent coastal plain in the northwestern coast of Bohai Bay were collected for diatom analyses and species *** ratio of the marine species Thalassionema nitzschioides to the intertidal-coastal species complex Cyclotella striata/stylorum serves as a novel proxy for assessing the strength of marine *** data,corrected for the local residence time effect,facilitated the construction of a diatom proxy-based marine influence curve for the study *** curve delineates the dynamics of marine influence and their correlations with paleo-climate fluctuations and the East Asian monsoon variability,as well as their role in chenier *** include:(1.eight periods of intensified marine influence have been documented since 7000 a BP in the study *** peak of each period,as determined by the diatom proxy,corresponds closely to the warm climatic phases and stronger East Asian summer monsoons,suggesting that the peaks marine influence indicate typically the periods of climatic warmth and monsoon activity intensification in the region;(2)a strong correlation exists between the development of cheniers and marine influence,and chenier formation began with the increasing marine influence and terminated at the end of warm periods as marine influence *** climatic changes in the coastal area,as indicated by the diatom proxy,hold significant potential for future related research endeavors.

关键词： Bohai Bay diatom diatom-based marine influence curve paleo-climate Holocene

Prediction of soil organic carbon stock combining Sentinel-1.and Sentinel-2 images in the Zoige Plateau, the northeastern Qinghai-Tibet Plateau

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Ecological Processes 2024年第2期13卷 165-176页

作者： Junjie Lei Changli Zeng Lv Zhang Xiaogang Wang Chanhua Ma Tao Zhou Benjamin Laffitte Ke Luo Zhihan Yang Xiaolu Tang State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Sichuan Academy of geological {1. Sichuan Institute of Nuclear geological {1. College of Earth Sciences Chengdu University of Technology Tianfu Yongxing Laboratory

Background Soil organic carbon（SOC） is a critical component of the global carbon cycle, and an accurate estimate of regional SOC stock（SOCS） would significantly improve our understanding of SOC sequestration and cycles. Zoige Plateau, locating in the northeastern Qinghai-Tibet Plateau, has the largest alpine marsh wetland worldwide and exhibits a high sensitivity to climate fluctuations. Despite an increasing use of optical remote sensing in predicting regional SOCS, optical remote sensing has obvious limitations in the Zoige Plateau due to highly cloudy weather, and knowledge of on the spatial patterns of SOCS is limited. Therefore, in the current study, the spatial distributions of SOCS within 1.0 cm were predicted using an XGBoost model—a machine learning approach, by integrating Sentinel-1. Sentinel-2 and field observations in the Zoige *** The results showed that SOC content exhibited vertical distribution patterns within 1.0 cm, with the highest SOC content in topsoil. The tenfold cross-validation approach showed that XGBoost model satisfactorily predicted the spatial patterns of SOCS with a model efficiency of 0.59 and a root mean standard error of 95.2 Mg ha-1. Predicted SOCS showed a distinct spatial heterogeneity in the Zoige Plateau, with an average of 355.7 ± 1.3.1.Mg ha-1.ithin 1.0 cm and totaled 0.27 × 1.～9 Mg *** High SOC content in topsoil highlights the high risks of significant carbon loss from topsoil due to human activities in the Zoige Plateau. Combining Sentinel-1.and Sentinel-2 satisfactorily predicted SOCS using the XGBoost model, which demonstrates the importance of selecting modeling approaches and satellite images to improve efficiency in predicting SOCS distribution at a fine spatial resolution of 1. m. Furthermore, the study emphasizes the potential of radar（Sentinel-1. in developing SOCS mapping, with the newly developed fine-resolution mapping having important applications in land management, ecological resto

关键词： SOC Vegetation index Texture XGBoost Sentinel-1 Sentinel-2

Quaternary Activity Characteristics and Regional Tectonic Significance of the Jiulong Fault in Jiujiang,Jiangxi Province,China

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Journal of Earth Science 2024年第4期35卷 1107-1117页

作者： Xin Qi Yuyong Jiao Qinghua Li Bin Li Faculty of Engineering China University of GeosciencesWuhan430074China Wuhan Center China Geological SurveyWuhan430205China Institute of geological {1. China University of GeosciencesWuhan430074China

Obtaining geological and landform dislocation features,as well as the measured stratigraphic activity age,provides direct evidence to evaluate fault activity,which is more difficult to do in areas with low tectonic activity,such as eastern and central China.A detailed investigation of the fault activity,trenching,drilling joint geological profile,geological survey,and chronological analysis were used to obtain the spatial geometry,fault kinematics,and activity chronology of the Jiulong *** conclusions are as follows:(1.The Jiulong fault was a fracture zone composed of four branch faults,with a width of around 30–40 m and good extendibility,while the maximum surface rupture length was 373 m.(2)The Jiulong fault has many strata dislocations,and the dislocation distance decreased from bottom to top,demonstrating synsedimentary structure characteristics,with a maximum stratigraphic dislocation distance of 1..2 m.(3)Preliminary analysis suggested the Jiulong fault as a secondary fracture of the Xiangfan-Guangji fault zone and provided evidence of the southeastward extension of the Xiangfan-Guangji fault.A preliminary hypothesis purported the Xiangfan-Guangji fault as the seismogenic fault of the Ms 5.0 magnitude earthquake in 1.1..(4)According to OSL and ESR dating analyses,the upper breakpoint of the Jiulong fault cuts into the Late Pleistocene Xingang Formation(Qp3x)strata,and the latest active age of the Jiulong fault was 57.6 *** chronology analysis confirmed an active fault from the Late Pleistocene and identified a weak tectonic in Jiujiang Province,which represents the largest active fault outcrop uncovered in the area so *** study provides evidence and research materials for the evaluation of fault activity and seismic stability in this region.

关键词： active fault regional tectonic earthquakes seismic intensity tectonics

Landslide Research at the british {1. survey:Capture,Storage and Interpretation on a National and Site-Specific Scale

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Acta Geologica Sinica(English Edition) 2009年第5期83卷 991-999页

作者： Catherine PENNINGTON Claire FOSTER Jonathan CHAMBERS Gareth JENKINS british {1. survey KeyworthNottinghamshireNG12 5GGUK

Landslide research at the british {1. survey （BGS） is carried out through a number of activities, including surveying, database development and real-time monitoring of landslides. Landslide mapping across the UK has been carried out since BGS started {1. mapping in 1.35. Today, BGS geologists use a combination of remote sensing and ground-based investigations to survey landslides. The development of waterproof tablet computers （BGS＇SIGMAmobile）, with inbuilt GPS and GIS for field data capture provides an accurate and rapid mapping methodology for field surveys. Regional and national mapping of landslides is carried out in conjunction with site-specific monitoring, using terrestrial LiDAR and differential GPS technologies, which BGS has successfully developed for this application. In addition to surface monitoring, BGS is currently developing geophysical ground-imaging systems for landslide monitoring, which provide real-time information on subsurface changes prior to failure events. BGS＇s mapping and monitoring activities directly feed into the BGS National Landslide Database, the most extensive source of information on landslides in Great Britain. It currently holds over 1. 000 records of landslide events. By combining BGS＇s corporate datasets with expert knowledge, BGS has developed a landslide hazard assessment tool, GeoSure, which provides information on the relative landslide hazard susceptibility at national scale.

关键词： landslide National Landslide Database GeoSure hazard LiDAR geophysics

Zircon U-Pb ages in the Nuratau ophiolitic mélange in the southern Tianshan,Uzbekistan:Implication for the closure of Paleo-Asian Ocean

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China Geology 2024年第2期7卷 365-368,I0004-I0007页

作者： Kai Weng Ji-fei Cao Divayev-Farid Karibovich Jahongir-Jurabekovich Movlanov Bo Chen Zhong-ping Ma Xi’an Center of geological {1. China Geological SurveyXi’an 710119China The Center for Geoinnovation Technologies Doctor of Sciences in Geology and Mineralogy University of Geological ScienceTashkent 100060Uzbekistan

*** The Central Asian Orogenic Belt(CAOB),which is located between the European craton,Siberian craton,and Tarim-North China craton(Fig.1.),is the largest phanerozoic accretionary orogen in the *** resulted from the longterm subduction and accretion of the Paleo-Asian Ocean(PAO).The PAO has been in existence since at least the late Mesoproterozoic(about 1.20 Ma).However,there has been debate about the closing time of the PAO.

关键词： Asian Paleo Tianshan

Deep-large faults controlling on the distribution of the venting gas hydrate system in the middle of the Qiongdongnan Basin, South China Sea

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China Geology 2024年第1期7卷 36-50页

作者： Jin-feng Ren Hai-jun Qiu Zeng-gui Kuang Ting-wei Li Yu-lin He Meng-jie Xu Xiao-xue Wang Hong-fei Lai Jin Liang National Engineering Research Center of Gas Hydrate Exploration and Development Guangzhou 511458China Guangzhou Marine geological {1. China Geological SurveyGuangzhou 511458China China geological {1. Ministtry of Natural ResourcesBeijing 100037China

Many locations with concentrated hydrates at vents have confirmed the presence of abundant thermogenic gas in the middle of the Qiongdongnan Basin(QDNB).However,the impact of deep structures on gasbearing fluids migration and gas hydrates distribution in tectonically inactive regions is still *** this study,the authors apply high-resolution 3D seismic and logging while drilling(LWD)data from the middle of the QDNB to investigate the influence of deep-large faults on gas chimneys and preferred gasescape *** findings reveal the following:(1.Two significant deep-large faults,F1.and F2,developed on the edge of the Songnan Low Uplift,control the dominant migration of thermogenic hydrocarbons and determine the initial locations of gas chimneys.(2)The formation of gas chimneys is likely related to fault activation and *** chimney 1.is primarily arises from convergent fluid migration resulting from the intersection of the two faults,while the gas chimney 2 benefits from a steeper fault plane and shorter migration distance of fault F2.(3)Most gas-escape pipes are situated near the apex of the two *** reactivations facilitate free gas flow into the GHSZ and contribute to the formation of fracture‐filling hydrates.

关键词： Venting gas hydrates Deep-large faults Gas chimney Gas-escape pipes High-resolution 3D seismic Logging while drilling Qiongdongnan Basin South China Sea

Regional trends and petrologic factors inhibit global interpretations of zircon trace element compositions

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Geoscience Frontiers 2024年第5期15卷 300-307页

作者： Nick M.W.Roberts Christopher J.Spencer Stephen Puetz C.Brenhin Keller Simon Tapster Geochronology and Tracers Facility British Geological SurveyNottingham NG125GGUK Department of geological Sciences and geological Engineering Queen’s UniversityKingstonOntarioCanada Atkinson Dr Suite 704HonoluluHI 96814USA Department of Earth Sciences Dartmouth CollegeHanoverNew HamphireUSA

The trace element composition of zircon reveals information about the melt that they are derived from,as such,detrital zircon trace element compositions can be used to interrogate melt compositions,and thus the evolution of the continental crust in time and ***,we present a global database of detrital zircon compositions and use it to test whether average global trends for five common petrogenetic proxies truly represent secular changes in continental *** demonstrate that the secular trend is broadly comparable across continental regions for Ti-in-zircon temperatures,but for other trace element ratios interrogated,secular trends are highly variable between continental *** trace element ratios result from multiple petrologic variables,we argue that these petrogenetic proxies can be overinterpreted if projected to global geologic *** particular,we caution against the interpretation of crustal thickness from trace elements in zircon,and we argue that our results negate current hypotheses concerning secular changes in crustal thickness.

关键词： Detrital zircon Trace elements Secular change Eu anomaly Crustal thickness

Significant lake expansion has accelerated permafrost degradation on the Qinghai-Tibet Plateau

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Journal of Mountain Science 2024年第1期21卷 68-83页

作者： LI Qingpeng LIU Wenhui LIU Hairui ZHOU Guanghao SONG Xianteng LI Qing LUO Bingnan SONG Bangxu ZHANG Qi Department of geological Engineering Qinghai UniversityXining 810016China College of Eco-Environmental Engineering Qinghai UniversityXining 810016China Xining Center for Integrated Natural Resources survey China Geological SurveyXining 810000China

In recent years, lakes on the Qinghai-Tibet Plateau have become more responsive to climate change. In September 201., Zonag Lake in Hoh Xil experienced sudden drainage, the water eventually flowed into Yanhu Lake, which caused Yanhu Lake to continue to expand. The potential collapse of Yanhu Lake could directly threaten the operational safety of the adjacent Qinghai-Tibet Highway, Qinghai-Tibet Railway. To explore the implications of expanding lakes on the surrounding permafrost, we selected Hoh Xil Yanhu Lake on the Qinghai-Tibet Plateau to study the effect of lake expansion on permafrost degradation. The permafrost degradation in the Yanhu Lake basin from October 201. to December 2022 was inverted using Sentinel-1.satellite image data and small baseline subset interferometry synthetic aperture radar(SBAS-In SAR) technology. Additionally, permafrost degradation from February 2007 and February 201. was analyzed using advanced land observing satellite phased array-type L-band synthetic aperture radar(ALOS PALSAR) satellite images and differential interferometric synthetic aperture radar(D-In SAR) technique. The results showed that the permafrost around Yanhu Lake experienced accelerated degradation. Prior to the expansion of Yanhu Lake, the average annual deformation rate along the line of sight(LOS) direction was 6.7 mm/yr. After the expansion, the rate increased to 20.9 mm/yr. The integration of spatial-temporal distribution maps of surface subsidence, Wudaoliang borehole geothermal data, meteorological data, Yanhu Lake surface area changes, and water level changes supports the assertion that the intensified permafrost degradation could be attributed to lake expansion rather than the rising air temperature. Furthermore, permafrost degradation around Yanhu Lake could impact vital infrastructure such as the adjacent Qinghai-Tibet Highway and Qinghai-Tibet Railway.

关键词： Lake expansion SBAS-InSAR D-InSAR Permafrost deformation Qinghai-Tibet Plateau

Impact of water table on hierarchically nested groundwater flow system

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Journal of Groundwater Science and Engineering 2024年第2期12卷 119-131页

作者： Jun Zhang Rong-zhe Hou Kun Yu Jia-qiu Dong Li-he Yin Key Laboratory of Groundwater and Ecology in Arid and Semi-arid Areas Xi'an Center of Geological SurveyChina Geological SurveyXi'an 710054China

Water table configuration gives rise to hierarchically nested groundwater flow ***,there remains a lack of comprehensive understanding regarding the controlling factors of water table and its impact on flow ***,it remains challenging to identify characteristics of water table space variation through limited groundwater observations at the regional *** on two ideal two-dimensional cross-section analytical models,this study presents a simplified approach to preliminarily assess the nonlinear interactions between water table variation and three driving factors:Topography,geol-ogy and *** criteria,C1.and C2,are utilized to address issues at different scales ranging from basin to local:(i)the influence of various factors on water table configuration;and(ii)the influence of water table on groundwater flow ***,the Ordos Plateau is taken as an example to explore the role of the water table in nested groundwater systems using the provided approach and *** applica-tion of this approach in the Ordos Plateau demonstrates its appropriateness as a practical method for prelim-inarily determining the characteristics of water table configuration and its impact on flow *** study explores the mechanism influencing spatial variation in the water table and improves understanding of the interaction between topography,geology,and climate on groundwater flow patterns.

关键词： Water table configuration Groundwater flow pattern Analytical models Top boundary condi-tions Ordos Plateau