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Source of silica and its implications for organic matter enrichment in the Upper Ordovician-Lower Silurian black shale in western Hubei Province,China:Insights from geochemical and petrological analysis

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Petroleum Science 2022年第1期19卷 74-90页

作者： Quan-Sheng Cai Ming-Yi Hu Bao-Min Zhang Ngong Ngia An Liu Rui-Quan Liao Oumar Kane Hai Li Zhong-Gui Hu Qing-Jie Deng Jun-Jun Shen School of Geosciences Yangtze UniversityWuhanHubei 430100China Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education(China University of Geosciences) WuhanHubei 430074China Wuhan Center of China geological survey WuhanHubei 430205China Department of Geology University of BueaP.O.Box 63BueaSouthwestCameroon School of Petroleum Engineering Yangtze UniversityWuhanHubei 430100China

To improve the understanding of the relationship between silica source and organic matter accumulation,the origin of silica and its implications for organic matter enrichment in the Upper OrdovicianLower Silurian(O_(3)w-S_(1)l)black shale in western Hubei Province in the middle Yangtze area,were investigated through geochemical and petrological *** results show that the O_(3)w-S_(1)l black shale is mainly composed of five lithofacies with varying graptolite abundance,total organic carbon(TOC),and silica *** silica and terrigenous siliciclastic input constitute the main silica sources in O_(3)w-S_(1)l black shale and they exhibit an upward inverse variation trend interpreted to be related to sea-level ***,with the increase in biogenic silica content or decrease in terrigenous siliciclastic input,TOC values in black shale initially rise and then fall,which is different from originally expected simple linear *** infer that organic matter enrichment and the distribution of silica from different origins are controlled by sea-level changes and variations in terrigenous input in a continental shelf with little hydrothermal *** environment with appropriate sea level and terrigenous input should be most favorable for organic matter accumulation,rather than one with excessive high sea level and less terrigenous input.

关键词： Biogenic silica Terrigenous siliciclastic input Organic matter enrichment Black shale Continental shelf Sea-level change Wufeng-Longmaxi formations

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Insights into the Tectonic Fractures in the Yanchang Formation Interbedded Sandstone-Mudstone of the Ordos Basin Based on Core Data and Geomechanical Models

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Acta Geologica Sinica(English Edition) 2015年第6期89卷 1986-1997页

作者： JU Wei SUN Weifeng HOU Guiting Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process Ministry of Education School of Resources and Geoscience China University of Mining and Technology School of Earth and Space Science Peking University The State Key Laboratory of Continental Tectonics and Dynamics institute of Geology Chinese Academy of Geological Sciences PetroChina Research institute of Petroleum Exploration and Development

The distribution and intensity of tectonic fractures within geologic units are important to hydrocarbon exploration and development. Taken the Upper Triassic Yanchang Formation interbedded sandstone-mudstone in the Ordos Basin as an example, this study used the finite element method（FEM） based on geomechanical models to study the development of tectonic fractures. The results show that the sandstones tend to generate tectonic fractures more easily than mudstones with the same layer thickness, and the highest degree of tectonic fractures will be developed when the sandstone-mudstone thickness ratio is about 5.0. A possible explanation is proposed for the tectonic fracture development based on two important factors of rock brittleness and mechanical layer thickness. Generally, larger rock brittleness and thinner layer thickness will generate more tectonic fractures. In interbedded sandstone-mudstone formations, the rock brittleness increases with the increasing mechanical layer thickness, hence, these two factors will achieve a balance for the development of tectonic fractures when the sandstone-mudstone thickness ratio reaches a specific value, and the development degree of tectonic fractures is the highest at this value.

关键词： tectonic fractures interbedded sandstone-mudstone formations sandstone-mudstonethickness ratio Yanchang Formation rock rupture value Ordos Basin

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Geochronology of the Dong Tso Ophiolite and the Tectonic Environment

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Acta Geologica Sinica(English Edition) 2013年第6期87卷 1604-1616页

作者： LI Jianfeng XIA Bin XIA Lianze XU Lifeng LIU Weiliang CAI Zhourong YANG Zhiqing State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry The Chinese Academy of Science School of Marine Sciences Sun Yat–Sen University Guang Dong Noferrous Metal Engineering Investigation Design institute School of Marine Sciences Sun Yat-Sen University Beijing SHRIMP Centre Chinese Academy of Geological Sciences

The wedge shaped Dong Tso ophiolitic block is distributed near the transition point from the western to the middle sub-belt of the Bangong-Nujiang suture *** ophiolite is characterized by well-developed cumulate rocks that are mainly composed of cumulate and massive *** the cumulate gabbros,the adcumulate amphiboles are distributed extensively around the plagioclase and residual pyroxene grains; hence,the rocks are named adcumulate *** this study,the formation age of the ophiolite has been estimated to be 166 ± 4 million years （Ma） by the sensitive high-resolution ion microprobe （SHRIMP） Ⅱ U-Pb isotopic analysis of the zircons from the adcumulate amphibole-gabbro; the 40Ar/39Ar plateau age was estimated to be 148.19 ± 1.53 Ma,which should represent the emplacement time of the ophiolite,by isotopic dating of the pure amphibole mineral from the *** different suits of volcanic lavas have been recognized in this *** purple colored pillow basalts have high TiO2 and P2O5 contents,and are rich in light rare earth elements （LREEs）,large-ion lithospheric elements （LILEs） and high-field-strength elements （HFSEs）,the characteristics that are the typical of the oceanic island basalt （OIB）.On the other hand,other massive basaltic andesites of celadon color are poor in MgO; rich in Fe2O3,LREEs,LILEs,and HFSEs; and especially characterized by negative Nb and Ta anomalies,the properties that establish the andesites as continental arc volcanic *** is concluded that hotspots had developed in the old Dong Tso basin,the oceanic basin that had been developing from middle Jurassic （166 Ma） or even before and emplaced northward in late Jurassic （about 148 Ma）.

关键词： Ophiolite SHRIMP U-Pb age 40Ar/39Ar age Tectonic evolution Dong Tso

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6th GEOCHIM ／UNESCO／SGA “Postgraduate certificated training course in geochemical exploration methods and their environmental applications”

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Episodes 2005年第1期28卷 59-60页

作者： Pasava, J Czech Geol survey Prague 11821 1 Czech Republic

It has been a tradition to organize very successful UNESCO Postgraduate Courses on Geochemical Prospecting Methods in the former Czechoslovakia from mid 70's. The first certificated course-GEOCHIM PRAHA UNESCO 1975 was launched on September 5, 1975 and lasted till October 25,1975. Since that time this course has been organized biannually by the Czech geological survey in Prague together with the Dionyz SEtúr geological survey in Bratislava and sponsored by the Division of Earth Sciences (UNESCO/Paris) and the International Association of Geochemistry and Cosmochemistry (IAGS). The course was specialized on both theoretical and practical training in classical geochemical prospecting methods.

关键词：研究生毕业训练课程地球化学开发方法环境应用

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Clay mineral compositions in the surface sediment of the Chanthaburi coast(northeastern Gulf of Thailand)and their implications on sediment provenance

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Journal of Oceanology and Limnology 2023年第5期41卷 1742-1752页

作者： Min CHEN Hongshuai QI Apitida WASUWATCHARAPONG Apichai KANCHANAPANT Wichien INTASEN Guobiao HUANG Xuan LIU Third institute of Oceanography Ministry of Natural ResourcesXiamen 361005China Department of Mineral Resources Ministry of Natural Resources and EnvironmentRatchathewiBangkok 10400Thailand Fujian Provincial Key Laboratory of Marine Physical and geological Processes Xiamen 361005China

Clay mineral composition represents an important tracer of sediment source area,migration processes,and paleoclimatic *** mineral analysis was performed on 15 surface sediment samples collected from the coast of Chanthaburi,*** show that the composition of clay minerals in the study area differs substantially from that in surrounding regions of the Gulf of *** clay minerals of the Chanthaburi coast are dominated by kaolinite(~56%),followed by smectite(~21%),illite(~14%),and low concentrations of chlorite(~8%).The average illite chemistry index and crystallinity are 0.93 and 0.32,*** analysis of the clay mineral composition of surface sediments in several typical areas around the Gulf of Thailand indicated that the clays of the Chanthaburi coast are mainly derived from parent rock weathering in the small watersheds of the Chanthaburi and Welu rivers and the surrounding *** input from the northern coast of the Gulf of Thailand(excluding the Mekong River)was previously considered negligible;however,the present results indicate that such input has impact on the eastern Gulf of *** warm humid climatic conditions in Southeast Asia are the primary factors that affect the strong chemical weathering in the study area,followed by the nature of the parent rock.

关键词： clay mineral surface sediment provenance coast of Thailand

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Lithospheric structure and geodynamics at the northern margin of Tibetan plateau

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Earthquake Science 2012年第5期25卷 433-450页

作者： Junmeng Zhao Fang Lu Zhichun Li Yang Wang Wentao Ma Xun Liu Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau ResearchChinese Academy of Sciences institute of Geology China Earthquake Administration Earthquake Administration of Hubei Province institute of Occupational Disease Protection for Laboring Hygiene of Hunan Province School of Earth Sciences and Resources China University of Geosciences institute of Geology Chinese Academy of Geological Sciences

A recent integrated geophysical survey has been completed along a transect from Baicheng, Xinjiang to Da Qaidam, Qinghai, China. In this study, wide-angle seismic reflection/refraction exploration with 10 shot points has been carried out to acquire the velocity structure of the crust and uppermost mantle. The earthquake focal mechanism solutions and terrestrial heat flow along the transect have also been obtained and analyzed. Based on the velocity structure of the crust and uppermost mantle along the transect, and combined with the focal mechanism solutions and terrestrial heat flow we develop a geodynamic model for the northern margin of the Tibetan plateau. This model reveals the detailed structure of the crust and uppermost mantle, determines the relationship of basin and range coupling, explores the deep dynamic setting for superposed basins, and establishes the northern boundary condition for Tibetan plateau research.

关键词： Tarim basin Altyn Tagh Qaidam basin Tibetan plateau geodynamic model

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Provenance of the Early Permian bauxitic claystone in Huayingshan region,Sichuan Basin,South China:Constraints from U-Pb ages and trace elements of detrital zircons

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Journal of Palaeogeography 2023年第2期12卷 211-228页

作者： Tian-Jia Liu Xun-Lian Wang Zhen-Tao Wang Xi-Fang Liu Peng-Cheng Ju Jia-Ai Zhong School of the Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Metallogeny and Mineral Resources Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an 710069Shaanxi ProvinceChina 405 geological Brigade of Sichuan Bureau of Geology and Mineral Resources Dujiangyan 611830Sichuan ProvinceChina

The Early Permian bauxite in the Sichuan Basin is an important part of karst-type bauxite deposits in South China Block and its provenance is poorly *** we present results of mineralogy,wholerock geochemistry,detrital zircon U-Pb ages and trace element compositions of the bauxitic claystone from the Lower Permian Dazhuyuan Formation and those of the siltstone from the underlying Lower Silurian Hanjiadian Formation in Huayingshan region,Sichuan Basin,South China Block to constrain the provenance of the bauxitic *** zircons from bauxitic claystone and siltstone have similar age spectra,and the ages of bauxitic claystone are classified into five groups of 2600-2200 Ma,1800-1600 Ma,1200-900 Ma,900-650 Ma,and 650-400 Ma *** of the siltstone are classified into four groups of 2600-2200 Ma,1200-900 Ma,900-650 Ma,and 650-400 Ma *** propose that the bauxitic claystone in the study region has mixed sources:the siltstone of the Lower Silurian Hanjiadian Formation probably constitutes the dominant source,and the Late Paleoproterozoic magmatic rocks along the western margin of the Yangtze Block are probably the secondary ***,the source materials of the Hanjiadian Formation siltstone are mainly sourced from Grenville-aged magmatic rocks in the Cathaysia Block and Neoproterozoic magmatic rocks in the Jiangnan orogen,with minor contributions from the underlying clastic sediments in the Cathaysia Block and Pan-African magmatic rocks in the orogen in eastern Gondwana.

关键词： Huayingshan Dazhuyuan Formation Bauxitic claystone Detrital zircon Mixed sources

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Design of Landscape Ecological Restoration for “Five Mining Areas” of the Laoqing Mountain in the Dianchi Lake Basin

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Journal of Landscape Research 2019年第2期11卷 95-98,103页

作者： ZHU Guofei HU Yeqing LONG Haijun CAI Fang SHE Lihua Kunming survey & Design institute of State Forestry Administration

Through analyzing basic conditions of the "five mining areas" in the Laoqing Mountain of the Dianchi Lake Basin, in Kunming City, South China, the ecological restoration design of "integrating engineering protection and biological restoration, building the landscape ecological security pattern of the Laoqing Mountain" was proposed. Considering the different ecological functional areas, varying engineering measures, greening patterns, and irrigation means were selected for the ecological restoration, including site management, vegetation restoration, management and utilization etc.. These ecological restoration measures will produce favorable ecological benefits, and also take landscape effect and sustainable development into consideration, which will contribute to the ecological restoration of the "five mining areas", and provide a scientific and feasible reference for the ecological restoration in China.

关键词： "Five mining areas" of Laoqingshan Mountain Landscape ecological restoration Site management Vegetation restoration Management and utilization

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Observed characteristics of tidal currents and mean flow in the northern Yellow Sea

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Journal of Oceanology and Limnology 2019年第2期37卷 461-473页

作者： BI Congcong BAO Xianwen DING Yang ZHANG Cong WANG Yu SHEN Biao WAN Kai College of Oceanic and Atmospheric Sciences Ocean University of China Qingdao 266100 China Physical Oceanography Laboratory/CIMST Ocean University of China and Qingdao National Laboratory for Marine Science and Technology Qingdao 266100 China The First institute of Oceanography State Oceanic Administration Qingdao 266061 China Laboratory for regional Oceanography and Numerical Modeling Qingdao National Laboratory for Marine Science and Technology Qingdao 266000 China National Marine Environmental Monitoring Center State Oceanic Administration Dalian 116023 China Beihai Off shore Engineering survey institute State Oceanic Administration Qingdao 266061 China

Several bottom-mounted Acoustic Doppler Current Profiler (ADCP) moorings were deployed in the northern Yellow Sea (NYS) during the four seasons of 2006–2007 and also the summertime of 2009. A synthesis analysis on the time-continuous records was performed to examine the characteristics and variations of tidal currents and mean flow over the observation period at these stations. Tidal currents accounted for ~75% of the total kinetic energy, with the absolute dominance of M2 constituent. Visible vertical variations of tidal flow were found on all sites, featured by the decrease of amplitude, increase of rotation rate as well as a decreasing trend of the phase for M2 component with depth. A notable exception was in the central NYS, where the maximum tidal currents occurred in the upper or middle layers (~20–40 m) instead of near the surface (<10 m). The observed mean flow was relatively weak, smaller than 15 cm/s. Velocity on the northern end of Yellow Sea Trough (YST) was characterized by low magnitude and an obvious layered structure vertically. In the Bohai Strait (BS) and the northern slope area, the currents weakened and the flow direction presented a major trend to deflect counterclockwise with depth in most observations. Summertime cyclonic circulation around the Yellow Sea Cold Water Mass (YSCWM), its intensification on the frontal zone and the Yellow Sea Warm Current (YSWC) for the winter season were all evident by our direct current measurements. However, the details of water exchange through the BS appeared partly diff erent from the traditionally-accepted pattern. The vertical diff erences of tidal and mean flow were larger in summer than that in winter, implying the influence of thermal structure to the local currents. Aff ected by the water stratification, mean flow usually reached its maximum near the thermocline in spring and summer, while showing a nearly uniform vertical distribution during winter.

关键词： northern Yellow Sea moored current measurements tidal currents mean flow thermal structure

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Clay with high fluorine and endemic fluorosis caused by indoor combustion of coal in southwestern China

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Acta Geochimica 2006年第S1期 79-80页

作者： Robert B. Finkelman US geological survey MS 956 National Center 12201 Sunrise Valley Drive Reston VA 20192 U.S.A.

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