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Eastern Ancient Terrane of the North China Craton

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Acta Geologica Sinica(English Edition) 2016年第4期90卷 1082-1096页

作者： wan yusheng {2. Shoujie Alfred KRONER DONG Chunyan XIE Hangqiang XIE Shiwen BAI Wenqian REN Peng MA Mingzhu {2. Dunyi Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Department of Geosciences University of Mainz D-55099 Mainz Germany

Based on the spatial distribution of ancient rocks and zircons, three ancient terranes older than ca. 2.6 Ga have recently been identified in the North China Craton, namely the Eastern, Southern, and Central Ancient Terranes. The Eastern Ancient Terrane is the best studied and understood of the three ancient terranes. It has a long geological history back to ca. 3.8 Ga ago and includes the areas of Anshan-Benxi, eastern Hebei, eastern Shandong and western Shandong. In Anshan-Benxi, several different types of 3.8 Ga rocks were discovered together with 3.1-3.7 Ga rocks, whereas 2.9-3.0 Ga K-rich granites and 2.5 Ga syenogranite occur on larger scales. In eastern Hebei, 3.0-3.4 Ga rocks and older detrital and xenocrystic zircons were identified. In eastern Shandong, there are a large volumes of 2.7 Ga and 2.9 Ga rocks. In western Shandong, early Neoarchean （2.6-2.7 Ga） intrusive and supracrustal rocks are widely distributed. Whole-rock Nd and zircon Hf isotope data suggest that both mantle additions and crustal recycling played important roles within the Eastern Ancient Terrane during almost every tectono-magmatic event. Most BIFs in the North China Craton are late Neoarchean in age and are distributed on continental crust along the western margin of the Eastern Ancient Terrane, probably suggesting that a stable environment was one of the key factors for the formation of large-scale BIFs.

关键词： Zircon age Hf isotopes Archean Eastern Ancient Terrane North China Craton

Geochemical records of carbon in recent sediments of Erhai Lake, China: Implication of effects of the Himalayas uplift on global environmental changes

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chinese Science Bulletin 1999年第S2期44卷 123-124页

作者： wan Guojiang~1, BAI Zhanguo~(1,2., wanG Haoran~1 and HUANG Ronggui~1 1. State Key Laboratory of Environmental Geochemistry, {2. of Geochemistry, chinese academy of Sciences, Guiyang 550002. China 2. State Key Laboratory of Plant Nutrition Research of chinese Ministry of Agriculture, {2. of Soil and Fertilizer, chinese academy of Agricultural Sciences, Beijing 100081, China

THE formation and uplift of the Himalayas and the Tibetan Plateau may have been responsible for the past150 Ma global environmental changes, resulting in the development of a three-tiered landform in southernChina. The Yunnan-Guizhou Plateau, as the middle tier in eastern slope of the Himalayas, has beencomplex environmental unit with great altitude gradients and plateau landform characters. Both monsoonsfrom the Pacific and the Indian resulting in apparent environmental changes on variable time scales influence it. Environmental geochemical effect of low latitude-high altitude could be yielded, and well recorded in the geological bodies in this region. To build and verify a quantitative model of environmental evolution it is necessary to obtain high-resolution data of elemental cycles and mass equilibrium.

关键词： records sediments Erhai Lake Himalayas uplift global environmental changes.

四川盆地东缘白马地区常压页岩气开发地质评价

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地质科技通报 2024年第4期43卷 53-61页

作者：刘超包汉勇万云强中国石油化工股份有限公司江汉油田分公司勘探开发研究院武汉430223

涪陵气田是我国第一个实现商业开发的页岩气田,近几年年产气量稳定在70亿m^(3.以上,开发效果良好。随着开发需求不断增大,开发对象由焦石坝等高压页岩气藏逐步转向了白马常压页岩气藏。2.2.年白马地区提交探明储量1048.83.m^(3.,地质... 详细信息

涪陵气田是我国第一个实现商业开发的页岩气田,近几年年产气量稳定在70亿m^(3.以上,开发效果良好。随着开发需求不断增大,开发对象由焦石坝等高压页岩气藏逐步转向了白马常压页岩气藏。2.2.年白马地区提交探明储量1048.83.m^(3.,地质资源基础得到夯实,而开发地质评价与目标优选是实现储量有效动用第一环。以分析化验、测井解释、地震预测、压裂试气资料为基础,开展白马地区常压页岩气开发有利层段与有利目标评价研究。研究结果表明,白马地区奥陶系五峰组-志留系龙马溪组发育深水陆棚相富有机质页岩,其中深水陆棚硅质页岩是开发最有利层段。明确了地层压力系数、孔隙度、天然裂缝、应力性质是常压页岩气开发地质评价的关键参数。以此为基础,建立了白马常压页岩气藏开发选区地质参数体系,优选白马向斜南部为开发建产第一目标,实现了规模效益建产,对常压页岩气开发具有重要借鉴意义。

关键词：白马地区页岩气常压开发地质奥陶系五峰组-志留系龙马溪组深水陆棚硅质页岩

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The Ashele VMS-type Cu-Zn Deposit in Xinjiang,NW China Formed in a Rifted Arc Setting

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The Ashele VMS-type Cu-Zn Deposit in Xinjiang,NW China Forme...

Palaeoproterozoic Khondalite Belt in the western North China Craton: New evidence from SHRIMP dating and Hf isotope composition of zircons from metamorphic rocks in the Bayan Ul-Helan Mountains area

中国科学院地质与地球物理研究所第十届(2.10年度)学术年会

作者： Bo wan,Lianchang ZHANG and Peng XIANG Key Laboratory of Mineral Resources,institute of {2. and Geophysics,{3. {3. of Sciences,Beijing,China

The Ashele Cu-Zn deposit is a typical VMS deposit in chinese Altay located in the southern margin of the Altaid *** deposit occurred in the polyphase fold system,and the main orebody is located at the hinge of the *** orebodies show lenticular form,and are stratabound by a suite of early to middle Devonian bimodal volcanic *** hosting basalt is low K tholeiite and characterized with high Mg,Fe,Ca and low K,*** basalts show flat REE pattern with Ce negative anomaly(Ce/Ce 0.73.0.76).Niobium,Ta, Zr,Hf are depleted and Rb,Ba,Th,U,Sr,Pb are enriched with respect to the *** the Sr and Nd isotopes show depleted properties,while the(Sr/Sr) and theε(t)range from 0.70469 to 0.70488 and 4.6 to 5.3.*** geochemical and isotopic data from the hosting basalt show that it originates from an island arc *** also report the S isotope data from the massive orebody,andδS‰change from 1.8‰to 5.6‰.The S isotope data provide evidence that the sulfur originates from a mixing source between magma and seawater *** propose that the mafic magma provides the ore-forming metal and some percentage of sulfur,while it also acts as a heat engine which makes the fluids leach the metal from the underlying volcanic *** the geological characteristics of the Ashele and geochemical data,and comparing with other Cu-Zn VMS deposits in the world,we propose that Ashele formed in *** arc setting.

关键词： Altaid orogen Ashele Cu-Zn VMS deposit island arc

来源： cnki会议评论

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chinese Science Bulletin 2007年第21期52卷 2984-2994页

作者： DONG ChunYan liu DunYi LI JunJian wan {2. ZHOU HongYing LI ChengDong YANG YueHeng XIE LieWen institute of geology Chinese Academy of Geological Sciences Beijing 100037 China Beijing SHRIMP Center Beijing 100037 China Tianjin institute of geology and Mineral Resources China Geological Survey Tianjin 300170 China institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Zircom U-Pb age and Hf isotope analyses were made on gneissic granite and garnet-mica two-feldspar gneiss from the Helanshan Group in the Bayan Ul-Helan Mountains area, the western block of the North China Craton (NCC). Zircons from the gneissic granite commonly show core-mantle-rim structures, with magmatic core, metamorphic mantle and rim having ages of 2.2.±2. Ma, 192.±2. Ma and 1856±12.Ma, respectively. The core, mantle and rim show similar Hf isotope compositions, with single-stage depleted mantle model ages (TDM1) of 2.55 to 2.55 Ma (19 analyses). Most of the detrital zircons from the garnet-mica two-feldspar paragneiss have a concentrated U-Pb age distribution, with a weighted mean 2.7Pb/2.6Pb age of 1978±17 Ma. A few detrital zircons are older (2.71 to 2.69 Ma). The age for metamorphic overgrown rim was not determined because of strong Pb loss due to their high U content. The zircons show large variation in Hf isotope composition, with TDM1 ages of 1999 to 3.47 Ma. In com- bination with previous studies, the main conclusions are as follows: (1) protolith of the khondalite se- ries in the Helanshan Group formed during Palaeoproterozoic rather than the Archaean as previously considered; (2. The results lend support to the contention that there is a huge Palaeoproterozoic Khondalite (metasedimentary) Belt between the Yinshan Mountains Block and the Ordos Block in the Western Block of NCC; (3. The widely-distributed bodies of early Palaeoproterozoic orthogneisses in the Khondalite Belt might be one of the important sources for detritus material in the khondalite series; (4) Collision between the Yinshan Block, the Ordos Block and the Eastern Block occurred in the same tectonothermal event of late Palaeoproterozoic, resulting in the final assembly of the NCC.

关键词：孔兹岩带古元古生代年代测定贺兰山

Cretaceous integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 1229-1289页

作者： Dangpeng XI Guobiao LI Shijun JIANG Xin RAO Tian JIANG Tianyang wanG Zuohuan QIN Yasu wanG Jianzhong JIA Muhammad KAMRAN Zhongye SHI Yuyang WU Panxi wanG Lixin SUN Qinggao ZENG Xiaoqiao wan State Key Laboratory of Biogeology and Environmental geology China University of GeosciencesBeijing 100083China College of Oceanography Hohai UniversityNanjing 213200China Key Laboratory of Palaeobiology and Petroleum Stratigraphy Nanjing Institute of Geology and PaleontologyChinese Academy of SciencesNanjing 210008China State Key Laboratory of Tibetan Plateau Earth System Environmentand Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China China National Offshore Oil Corporation Limited Beijing 100028China Shanghai Science and Technology Museum Shanghai 200120China Xizang Bureau of geological and Mineral Exploration and Development Lhasa 850000China Tianjin geological Survey Center of China geological Survey Tianjin 300170China

The Cretaceous Period is a vital time interval in deciphering the evolutionary history of the Neo-Tethys Ocean and the convergence of different plates and blocks across the Qinghai-Tibetan Plateau.A detailed stratigraphic framework and paleogeographic patterns are the basis for understanding the evolution of the Neo-Tethys Ocean and the formation of the QinghaiTibetan ***,the Cretaceous stratigraphy,biota,paleogeography,and major geological events in the Qinghai-Tibetan Plateau are analyzed to establish an integrative stratigraphic framework,reconstruct the paleogeography during the Cretaceous Period,and decode the history of the major geological *** Cretaceous rocks of the Qinghai-Tibetan Plateau and its surrounding area are predominantly marine deposits,with a small amount of interbedded marine-terrestrial and terrestrial *** Indus-Yarlung Tsangpo Suture Zone was responsible for the deposition of deep marine sediments dominated by ophiolite suites and radiolarian *** the south,the Tethys Himalayas and Indus Basin received marine sediments of varying depths and lithology;to the north,the Xigaze and Ladakh forearc basins are also filled with marine *** Lhasa Block,Karakorum Block,western Tarim Basin,and West Burma block consist of shallow marine,interbedded marine-terrestrial,and terrestrial *** Qiangtang Basin and other areas are dominated by terrestrial *** Cretaceous strata of the Qinghai-Tibetan Plateau and its surrounding areas are widely distributed and diversified,with abundant foraminifera,calcareous nannofossils,radiolarians,ammonites,bivalves,and *** the basis of integrated lithostratigraphic,biostratigraphic,geochronologic,and chemostratigraphic analyses,we proposed herein a comprehensive stratigraphic framework for the Cretaceous Period of the eastern *** analyzing the Cretaceous biota of different biogeographic zones from eastern Neo-Tethys and its surrounding a

关键词： Qinghai-Tibetan Plateau Tethys Cretaceous Stratigraphy Biota Paleogeography

U-Pb dating of zircon from the Central Zone of the East Kunlun Orogen and its implications for tectonic evolution

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Science China Earth Sciences 2008年第7期51卷 929-938页

作者： CHEN NengSong SUN Min wanG QinYan ZHANG KeXin wan {2. CHEN HaiHong Faculty of Earth Science China University of GeosciencesWuhan 430074China Department of Earth Sciences the University of Hong KongHong Kong SARChina Beijing SHRIMP Center Beijing 100037China State Key Laboratory of geological Processes and Mineral Resources in China University of Geosciences Wuhan 430074China

LA-ICP-MS and SHRIMP U-Pb dating of zircons from orthogneisses and amphibolite from the Central Zone of the Kunlun Orogen is reported in this paper. One orthogneiss sample has metamorphic zircons yielding weighted average 2.6Pb/2.8U age of 517.0 +5.0/-6.0 Ma, and the other orthogneiss sample con- tains zircons with inherited magmatic cores giving three population 2.7Pb/2.6Pb ages of 955 Ma, 895 Ma and 657 Ma for the magmatic protolith, and metamorphic recrystallized rims with peak 2.6Pb/2.8U ages of 559 +12.?17 Ma and 516 ± 13.Ma. The amphibolite yielded three populations of weighted average 2.6Pb/2.8U age of 482.0 +10/?8.0 Ma, 516.2.± 5.8 Ma and 549 ± 10 Ma for the metamorphic zircons. These dating results recorded the tectonothermal events that occurred in the early Paleozoic and the Pre- cambrian time. The records of the Cambrian magmatic-metamorphic event in the Qinling Orogen, the Altyn Tagh belt, north margin of the Qaidam Block and the Kunlun Orogen suggest that continental assembly probably occurred in the early evolutionary history of the Proto-Tethys.

关键词： zircon U-Pb dating East Kunlun Orogen Proto-Tethys tectonic evolution

Zircon and Monazite Ages Constraints on Devonian Magmatism and Granulite-Facies Metamorphism in the Southern Qaidam Block:Implications for Evolution of Proto-and Paleo-Tethys in East Asia

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Journal of Earth Science 2018年第5期29卷 1132-1150页

作者： Jin Ba Lu Zhang Chuan He Neng-Song Chen Timothy M.Kusky Qinyan wang yusheng wan Xiaoming {3. School of Earth Sciences China University of GeosciencesWuhan 430074China College of Earth Science Chengdu University of TechnologyChengdu 610059China Sichuan institute of geological Survey Chengdu 610081China Center for Global Tectonics China University of GeosciencesWuhan 430074China Beijing SHRIMP Center Beijing 100037China State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an 710069China

High-temperature magma generation process and granulite-facies metamorphism can provide important information about mantle-crustal interaction and tectonic evolution. The strongly peralu- minous monzonite pluton, the Jinshuikou cordierite granite on the southern margin of the Qaidam Block, can provide important information about the mantle-crustal interaction and constraints on tectonic tran- sition from Proto-Tethys to Paleo-Tethys. This pluton develops enclaves of mafic granulite, amphibolite and quartzofeldspathic rocks, and is cut by massive monzonitic leuco-granite veins. Zircon and monazite U-Pb dating for the cordierite granite, the granulite enclaves and a massive monzonitic leuco-granite vein reveal that the cordierite granitic magma was generated from Mesoproterozoic continental crust with protolith derived from a provenanee that was composed of 〉2.8 Ga old recycled crustal materials and re- corded a -1.7 Ga magmatic event. The continental crust underwent low-pressure granulite-facies metamorphism at -3.0 Ma ago, whereas the cordierite granite magmas was generated and emplaced during 3.0 Ma, followed by intrusion of the massive monzonitic leuco-granite vein at circa 3.0-3.0 Ma. These data suggest that after the final closure of Proto-Tethys Ocean spreading along the southern Qaidam Block at -42. Ma, break-off of the subducted slab or delamination of the lower crustal base and upwelling of the asthenospheric mantle beneath the southern Qaidam Block occurred before the Mid-Devonian, and that the initiation of the Paleo-Tethys tectonics might initiate near the end of Early-Carboniferous in the East Kunlun-Qaidam region, East Asia.

关键词： zircon and monazite U-Pb geochronology cordierite peraluminous granite low pressure granulite Proto- and Paleo-Tethys evolution East Kunlun-Qaidam.

SHRIMP U-Pb geochronology of the zircons from the Precambrian basement of the Qilian Block and its geological significances

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chinese Science Bulletin 2007年第19期52卷 2687-2701页

作者： Kuoan TUNG Huai-Jen YANG Houng-Yi YANG liu DunYi ZHANG JianXin wan {2. Chien-Yuan TSENG Department of Earth Sciences Cheng-Kung University Tainan 701 China Museum of Natural Science Taichung 404 China Beijing SHRIMP Centre Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China institute of geology Chinese Academy of Geological Sciences Beijing 100037 China

Origin and tectonic evolution of the Qilian Precambrian basement on NW China were investigated using zircon U-Pb ages with collaborating stratigraphic and paleontological evidence. Zircon grains were separated from two schists, two granitic gneisses and one mylonized gneiss and dated with SHRIMP. Seventy percent of sixty-one detrital zircon ages from two schists ranges from 0.88 Ga to 3.09 Ga, mostly within 1.0 Ga to 1.8 Ga with a peak at 1.6 Ga to 1.8 Ga, and twenty percent varies from 2.0 Ga to 2.5 Ga. A few falls in the Archean and Neoproterozoic periods. The two granitic gneisses were dated 93.±8 Ma and 918±14 Ma, whereas the mylonized granitic gneiss was dated 790±12.Ma. These ages represent two periods of magmatisms, which can be correlated with the early and late stages of magmatisms associated with the Jinningian movement on the Yangtze Blocks. The results from this and previous studies indicate that the ages of the Precambrian detrital zircons from the Qilian Block are widely distributed in the Proterozoic era, distinct from the North China Block which was stable in the Neo-Mesoproterozoic era. By contrast, the age histograms of the detrital zircons from the Qilian Block is similar to those from Precambrian basement of the Yangtze Craton. Therefore, it is suggested that the Qilian Block had a strong affinity toward the Yangtze Craton and might belong to the supercontinent Gond{3.a in the Neoproterozoic time. This inference is supported by Nd model age (TDM), stratigraphic, and paleontological evidence. It is further considered that the Qilian Block was rifted from the supercontinent Gond{3.a during late Sinian to form an isolated continent in the Proto-Tethyan Ocean, moving towards the Alaxa Block in the North China Craton. The part of Proto-Tethyan Ocean between the Qilian and Alaxa Blocks should correspond to the so-called Paleo-Qilian Ocean. Following the closure of the Paleo-Qilian Ocean in the early Paleozoic, the Qilian Block collided with the Alaxa B

关键词：地球年代学锆石前寒武纪古地中海特提斯海