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Track Fading and Its Applications in Archaeology, Tectonics and Geothermal Chronology in china

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Journal of Earth Science 2013年第4期24卷 645-651页

作者：郭士伦袁万明陈宝流黄慰文刘顺生 Department of Nuclear Physics China Institute of Atomic Energy School of Earth sciences and Resourses China University of Geosciences Department of Radioisotopes China Institute of Atomic Energy institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Guangzhou institute of Geochemistry Chinese Academy of Sciences

Track fading is a basic phenomenon in track science and has been the source of informa- tion in geosciences. This article summarizes the knowledge of track fading and gives some examples of successful applications of track fading in archaeology, tectonics and geothermal chronology in china. The applications of track fading are classified into 5 modes：（1） mode of complete fading （annealing）; （2. mode of partial fading; （3） use of the dependence of track fading on time and temperature; （4） use of the differences of track fading between coexisting minerals; and （5） use of fading-reduced track length. Track fading mechanisms hints that scientists in geothermal chronology should adopt microprobes for quantitative elemental analysis to determine the detailed chemical compositions of each mineral grain or at least of the grains from each position of {2. structures in order that one becomes well aware of the relation between the track fading behavior and chemical compositions of the mineral used.

关键词： track fading archaeology tectonics geothermal chronology.

Giant Mineral Deposits and Their Geodynamic Setting in the Lanping Basin,Yunnan,china

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Giant Mineral Deposits and Their Geodynamic Setting in the L...

Hydrocarbon accumulation in network and its application in the continental rift basin

中国科学院地质与地球物理研究所2.04学术年会

作者： XUE Chunji~1,LIU Shuwen~1,chen Yuchuan~2.ZENG Rong~1 and ZHAO Shihua~1 1 College of Earth sciences and Resources,Chang’an University,Xi’an,Shaanxi 710054 2.2.,Beijing 100037

There are giant mineral deposits,including the Jinding Zn-Pb and Baiyangping Ag-Co-Cu,and other important mineral deposits(e.g.,Baiyangchang Ag-Cu,Jinman Cu deposits,etc.) in the Lanping Mesozoic-Cenozoic Basin,Yunnan Province,*** tabular ore-bodies and some veins hosted in terrestrial clastic rocks of the Mesozoic-Cenozoic age and no outcropping of igneous rocks in the giant deposits lead to the proposal of syngenetic origin,but the giant mineral deposits are not stratabound(***,sandstone- and Sedex-type).They formed in a continental red basin with intense crust *** mineralization is controlled by structures and lithology and occurs in different strata, and no sedimentary nature and no exhalative sediments are identified in the *** deposits show some relations with organic matter(now asphalt and petroleum) and evaporates(gypsum).The middle-low-temperature(mainly 110℃to 2.0℃) mineralization took place at a depth of about 0.9 km to 3.1 km during the early Himalayan(58 to 67 Ma).The salinity of ore-forming fluids is surprisingly low(1.6%to 18.0 wt%(NaCl)).Affected by the collision of the Indian and Eurasian plates,the mantle is disturbed under the Lanping *** large-scale mineralization is closely linked with the geodynamics of the crust movement,the mantle and mantle-flux upwelling and igneous *** mineral deposits and their geodynamic setting are unique in the Lanping Basin.

关键词： giant Jinding Zn-Pb deposit giant Baiyangping Ag-Co-Cu deposit ore geology geodynamic setting Lanping Basin Yunnan Province china

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Science china Earth sciences 2008年第S2期51卷 88-100页

作者： PANG XiongQi1,2.chen DongXia1,ZHANG ShanWen3,HAO Fang1,LIU Zheng1,LIU KeYu3,SONG GuoQi4,WANG YongShi4,LUO XiaoRong5 & WU XiaoChun61 State Key Laboratory of Petroleum Resource and Prospecting,chinese University of Petroleum,Beijing 102.49,{2. 2.Basin and Reservoir Center,chinese University of Petroleum,Beijing 102.49,{2. 3 SINOPEC Shengli Oilfield,Dongying 2.7051,{2. 4 CSIRO Petroleum,P. O. Box 1130,Bentley,WA 6102.Australia 5 institute of geology and Geophysics,chinese academy of Science,Beijing 10002.,{2. 6 china National Petroleum Corporation,Beijing 10072.,{2. State Key Laboratory of Petroleum Resource and Prospecting Chinese University of Petroleum Beijing China Basin and Reservoir Center Chinese University of Petroleum Beijing China SINOPEC Shengli Oilfield Dongying China CSIRO Petroleum Bentley Australia institute of geology and Geophysics Chinese Academy of Science Beijing China china National Petroleum Corporation Beijing China

The concept of hydrocarbon accumulation in network was presented on basis of the overall analysis of the formation and evolution characteristics of the continental faulted basin and of the systemic re-search on the major controlling factors on the hydrocarbon accumulation. The hydrocarbon accumu-lation in network can be defined as hydrocarbon accumulation in a three-dimensional network system which is constituted by the hydrocarbon migration passages under multiple dynamics,following the hydrocarbon generation from source rocks. The research shows that the hydrocarbon accumulation in network is composed of four elements,i.e.,hydrocarbon source (source rock kitchen),hydrocarbon accumulation terminal (trap),network pathway connecting source and terminal (transporting system),and network potential driving hydrocarbon migration in the network pathway (migration dynamics). Compared with other networks,hydrocarbon accumulation in network has three basic characteristics: the irreversible geological process of material and information flow in the network; the loss of material and information in the flow process in the network; the multiple dynamics in the flow process. Interac-tion of all the elements in the geological process can be called hydrocarbon accumulation in network. There are three basic models for hydrocarbon accumulation in network,that is,hydrocarbon accumu-lation in the network source area,hydrocarbon accumulation in the network pathway,and hydrocarbon accumulation in the network terminal. The key in the application of the hydrocarbon accumulation models in network in practice is to confirm the major accumulation stage and the function range of the four elements controlling the hydrocarbon firstly,to predict the profitable accumulation region by su-perposition of the favorable areas confirmed by four elements consequently,and to evaluate the oil-bearing property of the trap as well as confirm drilling targets. This paper takes the Dongying De-pression in the

关键词： continental rift basin hydrocarbon accumulation theory hydrocarbon network hydrocarbon accumulation in network Bohai Bay Basin

Evolution of the upper earth crust in the southwest area of yangtze terrain and its influence on the formation of Carlin-type Au ore deposits

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chinese Science Bulletin 1999年第S2期44卷 220-221页

作者： chen Xiaozhong and LI Chaoyang Open Laboratory Laboratory of Ore Geochemistry, {2. of Geochemistry, chinese academy of sciences, Guiyang 550002. china Open Laboratory Laboratory of Ore Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

1 Outline of the yangtze terrain THE northwestern area of Sichuan and the joined area of Yunnan, Guizhou and Guangxi are the two majorfields where lots of Carlin-type Au ore deposits are located. Both of them belong to the western area ofyangtze terrain. The evolution of yangtze terrain affected profoundly the geological evolution in these areas. Many epithermal ore deposits, such as Carlin-type gold, lead, zinc, mercury, stibium and arsenic,occur in the these areas, due to the evolution of crust in yangtze terrain. The foundation of yangtze terrain shows a structure of three stories, mainly composed of the Proterozoic clastic rocks and carbonic rocks that were involved in low-middle grade metamorphose. The meaningof the yangtze terrain changed according to several geological times, which can be said that the activity ofyangtze terrain changed in the past. The yangtze terrain undertook several processes of landmass hyper-

关键词： yangtze terrain extending basin Carlin-type Au ore deposit.

Mineralization of sediment-hosted ore deposits in reef-chert suite in china

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chinese Science Bulletin 1999年第S2期44卷 271-272页

作者： chen Duofu, chen Xiangpei, GAO Jiyuan, PAN Jingming and chen Guangqian Guangzbou institute of Geochemistry, chinese academy of sciences, Guangzhou 510640, china Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

THE reef-chert suite, named by chen, mainly consists of four types of rocks, with reef carbonate in thelower part, fine detrital rocks in the upper part, chert beds with ore bodies in the intermediate, and synchronous volcanic rocks either in this sequence or in the same sequence in the neighboring district. It isformed as a fixed and ordered suite in space and time, and is the comprehensive product of normal sedimentary process, biological process in extensional basin, hydrothermal sedimentary process near basinbase and magmatic process in the deep of lithosphere in the special geological setting. Many of thesediment-hosted ore deposits usually occur in such a suite in{2., such as Dajiangping pyrite deposit,Shuikoushan lead-zinc ore deposit, Changkeng gold-silver deposit, Dachang cassiterite-lead-zinc ore deposit, Xikuangshan stibium ore deposit, Changba-Lijiangou lead-zinc ore deposit, Baiyunebo

关键词： sediment-hosted deposits reef-chert suite china.

Bibliometric analysis of the status and trend of biological soil crusts research from 1912.to 2.2.

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Research in Cold and Arid Regions 2024年第2期16卷 98-108页

作者： XiaoJu yang FaSi Wu Long Li QingLin Guo ZongRen Yu SongCong chen XueYong Zhao Naiman Desertification Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China University of chinese academy of {2. Beijing 100049China National Research Center for Conservation of Ancient Wall Paintings and Earthen Sites Dunhuang AcademyDunhuangGansu 736200China Gansu Provincial Research Center for Conservation of Dunhuang Cultural Heritage DunhuangGansu 736200China Cultural Heritage Conservation and Design Consulting Co. Ltd.of Mogao GrottoesDunhuangGansu 736200China

Biological soil crusts(BSCs)play an important role in soil development and ecological function,and it is more important for quantitatively analyzing the processes and trends of BSCs to identify the advantages and disadvantages of BSCs research for the development and application of BSCs *** analysis of 2.186 BSCs literatures from Web of Science showed an exponential growth trend,as china and the United States as the top 2.in terms of publication *** quality publications are mainly from European and American countries,such as the United States,Germany and *** top 3 publishers are Journal of Arid Environments,Soil Biology&Biochemistry and Plant and Soil,and disciplines include ecology,environmental science,and soil science,etc..Research institutions mainly affiliate to the {2. academy of sciences,United States Department of the Interior,United States geological Survey,Hebrew University of Jerusalem,Consejo Superior de Investigaciones Cientificas,and Universidad Rey Juan *** mainly come from United States,Israel,Spain and *** are mainly from the National Natural Science Foundation of china,Spanish Government,{2. academy of sciences,and National Science Foundation of the United *** soil crusts(biocrusts,cyanobacteria,lichens,moss crusts,bryophytes),drylands,climate change,photosynthesis and desert are high-frequency *** research will focus on the driving mechanisms of BSCs on global biogeochemical cycles,maintaining global biodiversity on important ecological processes,global C,N,and P *** impact on biological invasion,sandstorms,and water balance,multifunctional and reciprocal mechanisms for maintaining the stability of desert and sandy ecosystems,and impact on the formulation of management policies for arid ecosystems,corresponding to global climate change,and the estimation of regional,local,and microscale distribution of BSCs based on machine deep learning modeling gradually fo

关键词： Biological soil crusts Bibliometric analysis Web of science CiteSpace VOSviewer

The Genesis and Evolution of Alpine-Type Ultrabasic Rocks in Western Junggar, Xinjiang

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Acta Geologica Sinica(English Edition) 1987年第2期 45-60+112-113页

作者： Peng Ligui Xi’an institute of geology and Mineral Resources,{2., Xi’an, Shaanxi

The alpine-type ultrabasic rocks of the studied area have undergone plastic deformation under a temperature about 800--12.0℃, a pressure about 0.9--1.68 GPa and differential stress of 0.2.-0.35 GPa in relatively dry conditions, forming ultrabasie mylonite with porphyroclastic and mylonitic textures, Primary crystallized silicate melt inclusions and melt-fluid inclusions are discovered in porphyroclastic minerals and ore-forming chrome spinel. These rocks are formed under relatively stable physico-chemical conditions through liquid immiscibility of silicate melts, at 12.0°-- 1300° and 1.1--1.38 GPa, equivalent to a depth of 40--50 km. No inclusion has been found in recrystallized secondary olivine and pyroxene, indicating that the plastic deformation happened after the formation of the rocks.

关键词： chen Xinjiang The Genesis and Evolution of Alpine-Type Ultrabasic Rocks in Western Junggar

Enhanced detection of freeze‒thaw induced landslides in Zhidoi county(Tibetan Plateau,china)with Google Earth Engine and image fusion

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Advances in Climate Change Research 2024年第3期15卷 476-489页

作者： Jia-Hui yang Yan-chen GAO Lang JIA Wen-Juan WANG Qing-Bai WU Francis ZVOMUYA Miles DYCK Hai-Long HE College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Department of Soil Science University of Manitob1Winnipeg MB R3T 2N2Canada Department of Renewable Resources University of Albert1Edmonton AB T6G 2H1Canad

Freeze‒thaw induced landslides(FTILs)in grasslands on the Tibetan Plateau are a geological disaster leading to soil *** landslides reduce biodiversity and intensify landscape fragmentation,which in turn are strengthen by the persistent climate change and increased anthropogenic ***,conventional techniques for mapping FTILs on a regional scale are impractical due to their labor-intensive,costly,and time-consuming *** study focuses on improving FTILs detection by implementing image fusion-based Google Earth Engine(GEE)and a random forest *** of multiple data sources,including texture features,index features,spectral features,slope,and vertical‒vertical polarization data,allow automatic detection of the spatial distribution characteristics of FTILs in Zhidoi county,which is located within the Qinghai‒Tibet Engineering Corridor(QTEC).We employed statistical techniques to elucidate the mechanisms influencing FTILs *** enhanced method identifies two schemes that achieve high accuracy using a smaller training sample(scheme A:94.1%;scheme D:94.5%)compared to other methods(scheme B:50.0%;scheme C:95.8%).This methodology is effective in generating accurate results using only~10%of the training sample size necessitated by other *** spatial distribution patterns of FTILs generated for 2.2. are similar to those obtained using various other training sample sources,with a primary concentration observed along the central region traversed by the *** results highlight the slope as the most crucial feature in the fusion images,accounting for 93%of FTILs occurring on gentle slopes ranging from 0°to 14°.This study provides a theoretical framework and technological reference for the identification,monitoring,prevention and control of FTILs in *** developments hold the potential to benefit the management of grassland ecosystem,reduce economic losses,and promote grassland sustainability.

关键词： Permafrost degradation Random forest Thaw slump Spatial distribution Tibetan Plateau

GIS-based risk analysis of debris flow:an application in Sichuan, southwest china

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International Journal of Sediment Research 2008年第2期23卷 138-148页

作者： B.F.DI1,2.3,N.S.chen1,P.CUI1,Z.L.LI1,Y.P.HE4,and Y.C.GAO1 3 1 Ph.D.,chengdu {2. of Mountain Hazards and Environment,CAS,chengdu 610041,china,Department of Architecture & Environment,Sichuan University,chengdu 610065,china,Graduate University of chinese academy of sciences,Beijing 100049,china,2.Prof.,Department of Architecture & Environment,Sichuan University,chengdu 610065,china,3 Graduate University of chinese academy of sciences,Beijing 100049,china 4 Department of Civil and Environmental Engineering,San Diego State University,5500 Campanile Dr.San Diego,CA 92.2.,USA Ph.D. Chengdu Institute of Mountain Hazards and Environment CAS Chengdu 610041 China Department of Architecture & Environment Sichuan University Chengdu 610065 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Prof. Department of Architecture & Environment Sichuan University Chengdu 610065 China Graduate University of chinese academy of {2. Beijing 100049 China Department of Civil and Environmental Engineering San Diego State University 5500 Campanile Dr. San Diego CA 92121 USA

Debris flow is a serious geologic hazard in *** is estimated that nationally debris flows cause up to 2.billion RMB(2.0 million US$) in damages and 300-600 deaths and injuries *** mitigate debris flow hazards,it is necessary to map,model,and identify zones of debris flow hazards and vulnerability as to inform the local people about the potential risk with a geographic information *** research presents a regional scale case study modeling debris flow risk(hazard and vulnerability) in Sichuan Province,Southwestern *** this area,3,2.0 debris flows have been identified and the spatial-temporal distribution and activity characteristics of them have been *** on the available meteorological data,a Digital Elevation Model with the rate of 1:2.0,000 and a regional geological map,the 2.-hr rainfall threshold(y) for debris flow occurrence is closely related(significant at 99% confidence level) to the index(x) defined using a geology factor(rock hardness:a) and a topographical factor(channel gradient:d) where y = 2. + 102.0 / x,in which x = 2.7 × ea + 1000 × *** discipline is constructive in developing the rainfall threshold for debris flow activity in remote mountainous areas that lack *** a given watershed,a four-level debris flow hazard map is developed by comparing the rainfall threshold to the design rainfall intensities with 50-,2.-,and 5-year average recurrence intervals,*** degree of debris flow vulnerability is determined by the watershed socio-economic conditions.A four-class debris flow risk map,at the final phase of the research,is generated by combining debris flow hazards and *** the debris flow risk assessment,the Sichuan Province is classified into the slight,moderate,severe and very severe regions,which accounts for 36%,19%,2.% and 2.% of total area respectively.

关键词： Debris flow Geographic information system Hazard Vulnerability Risk Rainfall threshold