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Tectonics induced switching of provenance during the Late Quaternary aggradation of the Indus River Valley, Ladakh, India

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Geoscience Frontiers 2019年第1期10卷 285-297页

作者： Ravish Lal H.S.Saini N.C.Pant S.A.I.Mujtaba Department of geology University of Delhi Geological survey of India

The Indus River flows through Ladakh, one of the driest and coldest places on earth, in a tectonically active domain. Fluvial, glaciofluvial, lacustrine and debris dominated sequences represent the Late Quaternary sedimentary record along the river course. Karakoram Fault, a major crustal scaled feature reported to be active during the Quaternary, is associated with the Indus River drainage. Linkages between a major, active fault and deposits formed during the activity period of the fault are explored using heavy mineral deduced provenance and Optically Stimulated Luminescence(OSL) *** deposits in a ~200 km long stretch of the Indus River have been examined for a ~80 ka period to decipher the climate linked aggradation history. Damming of the Indus River at ~79 ka and existence of the Spituk Lake for >30 ka is demonstrated. Using geology of the provenance in relation to the mineralogical attributes of the Quaternary deposits, the major drainage reorganization when the connection of the Tangtse Valley to the Indus was blocked, is inferred at ~73 ka. It is supported by the geologicalgeomorphological evidence. The study demonstrates the application of provenance linked mineralogy in terrestrial aggradation in a tectonically active region.

关键词： Karakoram Fault Indus Drainage reorganization Heavy minerals Aggradation

Stable isotope paleohydrology and chemostratigraphy of the Albian Wayan Formation from the wedge-top depozone,North American Western Interior Basin

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Science China Earth Sciences 2017年第1期60卷 44-57页

作者： Jeffrey B.ROSS Greg A.LUDVIGSON Andreas MOLLER Luis A.GONZALEZ J.D.WALKER Department of geology University of Kansas Kansas Geological survey University of Kansas

Understanding of the role of atmospheric moisture and heat transport in the climate system of the Cretaceous greenhouse world represents a major challenge in Earth system science. Stable isotopic paleohydrologic data from mid-Cretaceous paleosols in North America, from paleoequatorial to paleoArctic latitudes, have been used to constrain the oxygen isotope mass balance of the Albian hydrologic cycle. Over the range from 40°-50°N paleolatitude, sideritic paleosols predominate, indicating paleoenvironments with positive precipitation-evaporation （P-E） balances. Local exceptions occur on leeward side of the Sevier Orogen, where calcic paleosols in the wedge-top depozone record paleoenvironments with negative P-E balances in the orographic rain shadow. Stratigraphic sections in the Wayan Formation of Idaho （WF） were sampled from the wedge-top depozone. The units consist of stacked m-scale mudstone paleosols separated by m-scale sandstone-siltstone beds. Sections were sampled for organic carbon isotope profiles, and B-horizons from 6 well-developed paleosols were sampled for detrital zircons to determine maximum depositional ages. The first of these from the WF has produced a U-Pb concordia age of 101.0±1.1 Ma. This same WF section has produced a stratigraphic trend of upwardly decreasing δ18C values ranging from -24‰ upwards to -27‰ VPDB, suggesting correlation to the late Albian C15 C-isotope segment. Pedogenic carbonates from the WF principally consist of micritic calcite, with carbon-oxygen isotope values that array along meteoric calcite lines （MCLs） with δ18O values that range from -9.47‰ up to -8.39‰ VPDB. At approximately 42°N paleolatitude, these MCL values produce calculated paleoprecipitation values of-8.12‰ to -7.04‰ VSMOW, a range that is consistent with the estimates produced from other proxies at the same paleolatitudes across North America. These results indicate that despite the orographic rain shadow effect, the processes of meridional atmospheric moist

关键词： Cretaceous Paleoclimate Wayan Formation Pedogenic carbonates Geochronology

Potential and Suitability Evaluation of CO_2 Geological Storage in Major Sedimentary Basins of China,and the Demonstration Project in Ordos Basin

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Acta Geologica Sinica(English Edition) 2015年第4期89卷 1319-1332页

作者： GUO Jianqiang WEN Dongguang ZHANG Senqi XU Tianfu LI Xufeng DIAO Yujie JIA Xiaofeng Center for Hydrogeology and Environmental geology survey China Geological Survey China Geological survey College of Environmental and Resources Jilin University

From 2010 to 2012, the China Geological survey Center for Hydrogeology and Environmental geology survey （CHEGS） carried out the project ＂Potential evaluation and demonstration project of CO2 Geological Storage in China＂. During this project, we developed an evaluation index system and technical methods for the potential and suitability of CO2 geological storage based on China＇s geological conditions, and evaluated the potential and suitability of the primary basins for COz geological storage, in order to draw a series of regional scale maps （at a scale of 1：5000000） and develop an atlas of the main sedimentary basins in China. By using these tools, we delineated many potential targets for CO2 storage. We also built techniques and methods for site selection and the exploration and assessment of CO2 geological storage in deep saline aquifers. Furthermore, through cooperation with the China Shenhua Coal to Liquid and Chemical Co., Ltd., we successfully constructed the first coal-based demonstration project for CO2 geological storage in deep saline aquifers in the Yijinhuoluo Banner of Ordos in the Inner Mongolia Autonomous Region, which brought about the basic preliminary theories, techniques, and methods of geological CO2 storage in deep saline aquifers under China＇s geological conditions.

关键词： C02 geological storage potential and suitability evaluation atlas demonstration project

Phanerozoic Paleomagnetism Characteristics of the Qomolangma Area in Tibet

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Acta Geologica Sinica(English Edition) 2013年第2期87卷 517-527页

作者： ZOU Guangfu PAN Zhongxi ZHUANG Zhonghai ZHU Tongxing LI Jianzhong FENG Xintao Chengdu Institute of geology and Mineral Resources China Geological Survey

This paper conducts systematic test research on the 2920 paleomagnetic directional samples taken from Ordovician-Paleogene sedimentary formation in the north slope of Qomolangma in south of Tibet and obtains the primary remanent magnetization component and counts the new data of paleomagnetism the times. Based on the characteristic remanent magnetization component, it calculates the geomagnetic pole position and latitude value of Himalaya block in Ordovician- Paleogene. According to the new data of paleomagnetism, it draws the palaeomagnetic polar wander curve and palaeolatitude change curve of the north slope of Qomolangma in Ordovician-Paleogene. It also makes a preliminary discussion to the structure evolution history and relative movement of Himalaya bloc. The research results show that many clockwise rotation movements had occurred to the Himalaya block in northern slope of Qomolangmain the process of northward drifting in the phanerozoic eon. In Ordovician-late Cretaceous, there the movement of about 20.0~ clockwise rotation occurred in the process of northward drifting. However, 0.4° counterclockwise rotation occurred from the end of late Devonian epoch to the beginning of early carboniferous epoch; 6.0° and 8.0° counterclockwise rotation occurred in carboniferous period and early Triassic epoch respectively, which might be related with the tension crack of continental rift valley from late Devonian period to the beginning of early carboniferous epoch, carboniferous period and early Triassic epoch. From the Eocene epoch to Pliocene epoch, the Himalaya block generated about 28.0° clockwise while drifting northward with a relatively rapid speed. This was the result that since the Eocene epoch, due to the continuous expansion of mid-ocean ridge of the India Ocean, the neo-Tethys with the Yarlung Zangbo River as the main ocean basin closed to form orogenic movement and the strong continent-continent collision orogenic movement of the east and west Himalayas gener

关键词： paleomagnetic Phanerozoic tectonic movement the Qomolongma area Tibet

Middle Devonian-Tournaisian rocks and biota on Hainan Island,South China

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Science China Earth Sciences 2013年第11期56卷 1934-1941页

作者： ZHANG RenJie YAO HuaZhou WANG JianXiong TU Bing Wuhan Institute of geology and Mineral Resources China Geological Survey

On the basis of new paleontological data,the sequence and distributions of the Middle Devonian-Tournaisian rocks on Hainan Island have been sorted out for the first *** Devonian rocks include the Middle Devonian Jinbo Formation and the Upper Devonian Changjiang Formation,which are distributed in northwestern Hainan *** Jinbo Formation is represented by631 m of littoral facies deposits,and was intruded by the Yanshanian granite in the *** presence of chitinozoans Eisenackitina caster,Funsochitina pilosa,and Lagenochitina amottensis indicates the Givetian in *** Changjiang Formation is made up of 140 m of neritic facies rocks,and contains the Famennian conodonts Palmatolepis gracilis sigmoidalis,Polygnathus germanus,and corals Cystophrentis *** Devonian-Tournaisian transition beds,the lower part of the Jishi Formation,are composed of 61–129 m sandstone and siltstone,with gastropods Euomphalus *** brachiopods,and marked by conglomerate with the underlying Devonian *** middle-upper part of the Tournaisian Jishi Formation consists of 100–251 m clastic and carbonate rocks,containing abundant corals Pseudoularinia irregularis,conodonts Siphonodella isosticha,trilobites Weberiphillipsia linguiformis,and *** the basis of the occurrence of Xinanosprifer flabellum and Homotoma sp.,the Nanhao Formation in southern Hainan Island is now regarded as the Lower Silurian,instead of the previously designated Lower *** is confirmed that no Carboniferous rocks occurred in the area south to the Gancheng-Wanning Fault.

关键词： Devonian-Tournaisian rocks biota Hainan Island China

First Discovery of Gold Ore Bodies in the Lieryu Formation of the Liaohe Group in the Liaodong Area, China

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Acta Geologica Sinica(English Edition) 2017年第6期91卷 2342-2343页

作者： ZHANG Peng SHAO Jun LI Dongtao ZHAO Yan KOU Linlin BI Zhongwei Shenyang Institute of geology and Mineral Resources Shenyang Center of geological SurveyChina Geological Survey

Objective Numerous large deposits magnesite, and talc are Liaodong area, within of lead-zinc, gold, boron, distributed throughout the different layers of the Paleoproterozoic Liaohe Group. The Liaohe Group comprises five formations as follows （from bottom to top）. The Langzishan Formation consists of volcaniclastic rocks containing copper, cobalt, and iron deposits. The Lieryu Formation is a set of volcanic sedimentary facies accompanied by small amounts of continental-margin mixed volcanic sedimentary rocks containing boron and magnetite deposits. The Gaojiayu Formation consists of carbonaceous clay-bearing carbonate rocks and contains the most important graphite deposit. The Dashiqao Formation consists of carbonate rocks containing lead-zinc and magnesite deposits. The Gaixian Formation comprises clastic and volcaniclastic rocks, and contains the most important gold deposit. Historically, gold prospecting has focused on the Gaixian Formation; however, gold ore bodies have been discovered during iron ore mining in the Lieryu Formation （Dayinggou area）, indicating possible existence of larger gold deposits in the area.

关键词： First Discovery of Gold Formation of the Liaohe

Progradation of the Changjiang River delta since the mid-Holocene

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Science China Chemistry 2001年第S1期44卷 87-91页

作者： HoriKazuaki SaitoYoshiki 赵泉鸿汪品先李从先 Department of Earth and Planetary Science University of Tokyo Tokyo Japan Marine geology Department Geological Survey of Japan Tsukuba Japan Laboratory of Marine geology Tongji University Shanghai China

Subaqueous deltaic deposits with approximately 30 radiocarbon ages show that the Changjiang River delta was strongly affected by tides and that the delta progradation rate after 2 kaBP was almost double the rate before 2 kaBP. This change in the progradation rate correlates well with the active extension of the subaerial delta plain shown by previous work. Widespread human activities, such as farming, deforestation, and dike construction, probably resulted in an increase in sediment discharge to the river-mouth area.

关键词： Changjiang Yangtze sediment discharge delta progradation AMS radiocarbon dating human impact.

Tectonic evolution of the Western Kunlun orogenic belt in northern Qinghai-Tibet Plateau:Evidence from zircon SHRIMP and LA-ICP-MS U-Pb geochronology

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Science China Earth Sciences 2007年第6期50卷 825-835页

作者： ZHANG ChuanLin LU SongNian YU HaiFeng YE HaiMin Nanjing Institute of geology and Mineral Resources China Geological SurveyNanjing 210016China Tianjin Institute of geology and Mineral Resources China Geological SurveyTianjin 300170China

The Western Kunlun Range in northern Qinghai-Tibet Plateau is composed of the North Kunlun Terrane,the South Kunlun Terrane and the Karakorum-Tianshuihai Terrane. Here we report zircon SHRIMP and LA-ICP-MS U-Pb ages of some metamorphic and igneous rocks and field observations in order to pro-vide a better understanding of their Precambrian and Palaeozoic-early Mesozoic tectonic evolution. Based on these data we draw the following conclusions: (1) The paragneisses in the North Kunlun Terrane are likely of late Mesoproterozoic age rather than Palaeoproterozoic age as previously thought,representing tectonothermal episodes at 1.0―0.9 Ga and ～0.8 Ga. (2) The North Kunlun Terrane was an orogenic belt accreted to the southern margin of Tarim during late Mesoproterozoic to early Neopro-terozoic,the two episodes of metamorphisms correspond to the assemblage and breakup of Rodinia respectively. (3) The Bulunkuole Group in western South Kunlun Terrane,which was considered to be the Palaeoproterozoic basement of the South Kunlun Terrane by previous studies,is now subdivided into the late Neoproterzoic to early Palaeozoic paragneisses (khondalite) and the early Mesozoic metamorphic volcano-sedimentary series; the paragneisses were thrust onto the metamorphic vol-cano-sedimentary series from south to north,with two main teconothermal episodes (i.e.,Caledonian,460―400 Ma,and Hercynian-Indosinian,340―200 Ma),and have been documented by zircon U-Pb ages. (4) In the eastern part of the South Kunlun Terrane,a gneissic granodiorite pluton,which intruded the khondalite,was crystallized at ca. 505 Ma and metamorphosed at ca. 240 Ma. In combination with geochronology data of the paragneiss,we suggest that the South Kunlun Terrane was a Caledonian accretionary orogenic belt and overprinted by late Paleozoic to early Mesozoic arc magmatism.

关键词： North Kunlun Terrane South Kunlun Terrane Precambrian basement zircon SHRIMP and LA-ICP-MS U-Pb ages tectonic implications

Tertiary Calcareous Nannofossil Biostratigraphy in the North Part of the South China Sea

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Acta Geologica Sinica(English Edition) 1991年第3期65卷 321-338,343-344页

作者： Duan Weiwu and Huang Yongyang Gangzhou Marine Geological survey, Ministry of geology and Mineral Resources, Guangzhou Chang Zhijun and Sun Sheping Guangzhou Marine Geological survey Ministry of Geology and Mineral Resources Guangzhou

The marine Tertiary sequence in the north part of the South China Sea may be divided into 18 LateOligocene to Pliocene calcareous nannofossil zones and one unnamed Eocene assemblage based on an analysisof calcareous nannofossils from 40 offshore boreholes. The unnamed Eocene assemblage has been found onlyon the northeast margin of the Zhujiangkou basin. The 18 cakareous nannofossil zones of the Late Oligoceneto Pliocene were deposited in succession, but their development degrees are different. Among the 18 calcareousnannofossil zones, those corresponding to Martini's (1971) NN4- NN5 zones, NN11 zone and NN13-NN15zones are well developed, relatively persistent laterally and also widely distributed. They are the importantmarkers for the stratigraphical subdivision and correlation of the Upper Tertiary between the various basins inthe north part of the South China Sea. Based on the calcareous nannofossils and the sedimentsry features coup-led with the foraminifer zonation in certain basins, the present paper discusses the sedimentary characteristicsof the marine Tertiary and as well as the distribution and development of the sedimentary hiatus in the *** calcareous nannofossil markers for the Upper / Lower Tertiary and the Quaternary / Tertiary boundaries,and the characteristics and geological significance of the reworked calcareous nannofossils are also discussed inthe paper.

关键词： Tertiary Calcareous Nannofossil Biostratigraphy in the North Part of the South China Sea