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Basic Lithofacies-Succession Model for the Wumishan Cyclothems: Their Markov Chain Analysis and Regularly Vertical Stacking Patterns in the Third-Order Sequences

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 421-431页

作者： MEI Mingxiang, MA Yongsheng and GUO Qingyin Institute of earth sciences and Natural {2., China {3. of geosciences, beijing 100083.China Petrochemical Corporation (SINOPEC), beijing 10002. Institute of earth sciences and Natural {2. China University of Geosciences Beijing 100083 China Petrochemical Corporation (SINOPEC) Beijing 100029 [?]3.ei Mingxiang Male born in 1965 got his Ph.D. in geology at the China university of geosciences in 1993. He has been engaged in sedimentology and stratigraphy and is now serving as an associate professor in the China University of Geosciences.

The Mesoproterozoic Wumishan Formation in the Jixian section of Tianjin is a succession of 3.00-m-thick carbonate strata formed in a period of about 100 Ma (13.0±2. Ma-12.7±10 Ma). In this succession of strata, the carbonate metre-scale cyclic sequences belonging to peritidal type with an approximately symmetrical lithofacies-succession are best developed. The wide development of 1:4 stacking patterns shows that these metre-scale cyclic sequences are genetically related to the short-eccentricity cycles, which are called the Wumishan cyclothems that could truly represent sedimentary cycles. Generally, massive and thick-bedded calcareous dolomites and dolomitic limestones of stromatolite biostromes and thrombolite bioherms constitute the central part of the Wumishan cyclothems. The lower and upper parts consist of tidal flat dolostones, sandy-muddy dolostone and the top part is composed of lagoonal facies dolomitic shales with a paleosol cap. Therefore, an approximately symmetrical lithofacies-succession is formed. Many features such as the clear deepening and shoaling vectors of cyclothems, and all kinds of marks of fresh-water diagenesis indicate that the Wumishan cyclothems are the product of autocyclic sedimentation governed by allocyclic high-frequency sea-level changes. The results of a Markov chain analysis reaffirm the existence of the lithofacies-succession model of the Wumishan cyclothems. The boundaries of the Wumishan cyclothems are marked by the instantaneous exposed punctuated surface, which leads to the discrepancy between the cyclothems and the parasequences of the sequence stratigraphy terminology system. It is difficult to form a judgment that the time span of the Milankovitch cycles in the Precambrian is certainly equal to that of the Phanerozoic, but the regularly vertical stacking patterns of the seventh-order rhythms, sixth-order cyclothems and fifth-order parasequence sets still indicate their consistency with the duration of the Milankovitch cy

关键词： Wumishan cyclothems Markov chain analysis Mesoproterozoic Jixian section Tianjin

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A　New　Mid　Early　Pleistocene　Mammalian　FaunaDiscovered　in　Choukoutien，China　and　Its　Application　in　Biostratigraphy

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Journal of earth Science 1995年第1期14卷 41-47,120页

作者： Cheng Jie(Department of Geology and mineral resources, China {2. of {3.,beijing 100083.Cao Boxun(faculty of earth sciences, China {2. of {3.,Wuhan 43.074)Tian MingZhong(Department of Geology and mineral resources, China Unive

This paper deals with a new Early Pleistocene micromammalian fauna found in Choukonden (Zhoukoudian) and its application in *** new locality (east cave ), discovered in 1985,is located on the north slope of the Taipingshan Hill, about 2.km northeast of the Loc.1 in Choukoutien and is about 140-150m in altitude. At this locality,abundant fossil mammals are found in thick cave-fissure deposit. This fauna comprises 3.mammalian taxa. Based on the comparison of the fauna, as Well as the sporo-pollen, climate events and paleomagnetic polarity section with those in other areas,we come to the conclusion that the sediments (Taipingshan Formation) in east cave were formed during the Period about from 1.67 Ma B. P. to 0.97 Ma B. P., and the fauna is about 1.2. Ma B. P. in ags.

关键词： mid Early Pleistocene micromammalian fauna biostratigraphy Choukoutien.

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Petrogenesis of Indosinian volcanic rocks in Songpan-Garze fold belt of the northeastern Tibetan Plateau:New evidence for lithospheric delamination

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Science China earth sciences 2010年第9期53卷 1316-1328页

作者： CAI HongMing1,2. ZHANG HongFei1,2. XU WangChun1,2. SHI ZhangLiang1,2.& YUAN HongLin3.1 State Key Laboratory of Geological Processes and mineral resources, Wuhan 43.074, China 2.{2. of earth sciences, China university of geosciences, Wuhan 43.074, China 3.State Key Laboratory of Continental Dynamics, Northwest university, Xi’an 710069, China 1. State Key Laboratory of Geological Processes and mineral resources Wuhan 430074 China2. Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China3. State Key Laboratory of Continental Dynamics Northwest University Xi’an 710069 China

In the Songpan-Garze fold belt of the northeastern Tibetan Plateau, an Indosinian lithospheric delamination model has been proposed, based on previous investigation of widespread granitoids. However, this model lacks comparable information from volcanism in the area. During the Indosinian delamination in the Songpan-Garze fold belt, whether partial melting of litho- spheric mantle taken place is debated. This paper reports U-Pb zircon LA-ICP-MS ages, geochemical and Sr-Nd-Hf isotopic compositions from the Aba and Wasai calc-alkaline volcanic rocks in the central Songpan-Garze fold belt. Obtained magma crystallization ages are 2.0±3.Ma for the Aba andesite and 2.5±1 Ma for the Wasai andesite. These are consistent with magma crystallization ages of the late Indosinian granitoids in the Songpan-Garze fold belt that formed in a post-collisional tectonic setting. The Aba and Wasai andesites have distinct geochemical singnatures. The former has higher Al2.3. K2., Rb but lower Na2., Ba and Sr contents, suggesting differences in their magmatic evolution. The Aba andesites have ISr values of 0.7070-0.7076 and εNd(t) values of -3.9 to -5.3. and the Wasai andesites have ISr values of 0.7075-0.7077 and εNd(t) values of -3.6 to -3.9. Zircons show εHf(t) values of -3.7 to 0.3.for the Aba andesites and -2.7 to 5.5 for the Wasai andesites. Geochemical and Sr-Nd-Hf isotopic compositions indicate that fractional crystallization and crustal assimilation processes are not key roles for their magma evolution, implying that their chemical compositions are those of primary melts. We suggest that the magma of the Aba andesites originated predominantly from a crustal source, with a minor mantle-derived component. The source region of the magma was likely at the crust-mantle boundary. The magma of the Wasai andesites resulted from partial melting of lithospheric mantle, which was probably metasomatized by fluids so that it was amphibole bearing. The petrogenesis of the Aba and Wasai andesite

关键词： volcanism U-Pb dating geochemistry petrogenesis lithospheric delamination Songpan-Garze fold belt

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A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW China

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Science China earth sciences 2006年第2期49卷 154-162页

作者： LI Chunhai12. TANG Lingyu1, FENG Zhaodong3.4, ZHANG Hucai2. WANG Weiguo3.& AN Chenbang3.1. Nanjing Institute of Geology and Palaeontology, Chinese Academy of sciences, Nanjing 2.0008, China 2. Nanjng Institute of Geography and Limnology, Chinese Academy of sciences, Nanjing 2.0008, China 3. Environment and {2. College, Lanzhou university, Lanzhou 73.000, China 4. beijing Normal university, beijing 100875, China 1. Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Nanjng Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 3. Environment and resources College Lanzhou University Lanzhou 730000 China 4. beijing Normal university Beijing 100875 China

With the support of 18 AMS-14C data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 44.2.to 11 ka B.P. in the Jingning area. Over the period of 44―2. ka B.P. (MIS3., coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 2. ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3. further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.

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Chronological record of the Early Mesozoic underplating in the northern margin of North China—U-Pb chronometry of zircons in the Late Mesozoic andesite from Western Liaoning

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Progress in Natural Science:Materials International 2007年第8期17卷 943-947页

作者： Shao ji'an~(1,2.*) Zhang Hongfu~2.Liu Xiaoming~3.Li Zhitong~4 (1.School of earth and Space {3.,Peking {2.,beijing 100871,China 2.Institute of Geology and Geophysics and Key Laboratory of mineral resources,Chinese Academy of {3.,beijing 10002.,China 3.Key Laboratory of Continental Dynamics,Northwestern {2.,Xi'an 710069,China 4.Institute of Geology and mineral resources of Shenyang,Shenyang 11003.0}China) [a]School of earth and Space sciences Peking University Beijing China [b]Laboratory of mineral resources Chinese Academy of Sciences Institute of Geology and Continental Dynamics Beijing China [c]Key Laboratory of Continental Dynamics Northwestern university Xi'an China [d]Institute of Geology and mineral resources of Shenyang Shenyang China

Cathodoluminescence spectroscopic analysis of zircons in the uppermost sanukites of the early Cretaceous Yixian Forma- tion in Western Liaoning reveals zoning structures of the zircons in the volcanic rocks. LA-ICP-MS chronometry shows that the central part of the zircons is remnant zircon with a U-Pb dating of 2.4 Ma,which is consistent with the age of the Early Mesozoic underplating granulites,and that the periphery is zircon crystallizing out of the host magma with a U-Pb dating of 116 Ma,which is highly consistent with the Ar-Ar dating of the host volcanic *** of the clinopyroxenes xenocrystals in the sanukites are similar to those of the clinopyroxenes in the underplating granulites,indicating that the granulites accreted to the lower crust in the Early Mesozoic have been reformed and disrupted by the upwelling diapers of the asthenosphere and taken part in formation of the sanukites in the Late Mesozoic.

关键词： northern margin of North China Mesozoic volcanic rock U-Pb chronometry of zircon underplating granulite

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Geochemical characteristics and tectonic implications of HP-UHP eclogites and blueschists in southwestern Tianshan, China

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Progress in Natural Science:Materials International 2006年第6期16卷 624-632页

作者： AI Yongliang, ZHANG Lifei, LI Xuping and QU Junfeng (MOE Key Laboratory of Orogenic Belt and Crust Evolution, School of earth and Space sciences, Peking {2., {3. 100871, China School of geosciences and resources, China {2. of geosciences, {3. 100083. China) [a]MOE Key Laboratory of Orogenic Belt and Crust Evolution School of Earth and Space Sciences Peking University Beijing China [b]School of geosciences and resources China University of Geosciences Beijing China

Four rock assemblages in correspondence with two different tectonic settings have been recognized in the NEE-SWW extending HP-UHP metamorphic belt in southwestern Tianshan, northwest China. Eclogite assemblage EC1 is geochemically akin to alkaline within-plate oceanic island basalt (OIB). EC2.shows affinity to enriched mid-oceanic ridge basalt (EMORB). Rare earth element (REE) and other immobile trace element characteristics of blueschist assemblage BS1 resemble those of normal mid-oceanic ridge basalt (NMORB). These three assemblages are likely formed on a seamount setting, and the prevalent presence of carbonate minerals and om-phacite quartzite stripes/gobbets suggests ancient pelagic sediments including marls are probably developed upon the basaltic seamount. Whereas the geochemical characteristics of BS2.assemblage are of volcanic arc basalt-type. The seamount with the pelagic sediments on it is brought into the subduction zone, and volcanic arc basalts formed on the active continental margin and trench sediments are eroded and enwrapped in the subducting mass, they are altogether subjected to high to ultrahigh pressure metamorphism and subsequent exhumation towards surface. The HP-UHP metamorphic belt is thus interpreted as a subduct ion-accretionary complex formed by tectonic juxtaposition and imbrication of seamount, seafloor, trench and volcanic arc sequences during oceanic crust subduction.

关键词： southwestern Tianshan HP-UHP metamorphic belt snbduction-accretion complex trace element geochemistry.

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Geothermal Characteristics and Geological Implications of Major Tectonic Units in China

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Journal of earth Science 2000年第3期19卷 152-157页

作者： Wang Yang faculty of earth {2. and {3. resources, China university of geosciences, beijing 100083. China Wang Jiyang Institute of Geology and Geophysics, Chinese Academy of {2., beijing 10002., China Deng Jinfu faculty of earth Scie

On the basis of more than 900 heat flow data in China and the surrounding seas, the authors study the geothermal characteristics of major tectonic units in China. The spatial pattern of heat flow and other thermal parameters for lithosphere exhibit significant lateral variation, originating from the Cenozoic tectonothermal activities related to the subduction of the Pacific plate and the collision between India and Asia. The mechanical strength of the crust and the seismicity of tectonic units were strongly affected by geothermal characteristics of units. The crustal heat production rate also shows the lateral heterogeneity, implying the significant lateral variation of bulk composition of the crust in China.

关键词： heat flow effective elastic thickness heat production rate of crust China.

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Development of distributed time-variant gain model for nonlinear hydrological systems

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Science China earth sciences 2005年第6期48卷 713-723页

作者： XIA Jun1, 2. WANG Gangsheng1, TAN Ge1, YE Aizhong2.& G. H. Huang3.1. Key Laboratory of Water Cycle & Related Land Surface Processes, Institute of Geographic sciences and Natural {3. Research, Chinese Academy of sciences, beijing 100101, China 2. State Key Laboratory of Water {3. & Hydropower Engineering sciences, Wuhan university, Wuhan 43.072. China 3. faculty of Engineering, university of Regina, 3.3. Wascana Parkway, Regina, Sask., S4S 0A2. Canada Correspondence should be addressed to Xia Jun 1. Key Laboratory of Water Cycle & Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. State Key Laboratory of Water resources & Hydropower Engineering sciences Wuhan University 430072 Wuhan China 3. faculty of Engineering University of Regina 3737 Wascana Parkway S4S 0A2 Sask Regina Canada

In this paper, a rainfall-runoff modeling system is developed based on a nonlinear Volterra functional series and a hydrological conceptual modeling approach. Two models, i.e. the time-variant gain model (TVGM) and the distributed time-variant gain model (DTVGM) that are built on the platform of Digital Elevation Model (DEM), Remote Sensing (RS) and Unit Hydro-logical Process were proposed. The developed DTVGM model was applied to two cases in the Heihe River Basin that is located in the arid and semiarid region of northwestern China and the Chaobai River basin located in the semihumid region of northern China. The results indicate that, in addition to the classic dynamic differential approach to describe nonlinear processes in hy-drological systems, it is possible to study such complex processes through the proposed sys-tematic approach to identify prominent hydrological relations. The DTVGM, coupling the advan-tages of both nonlinear and distributed hydrological models, can simulate variant hydrological processes under different environment conditions. Satisfactory results were obtained in fore-casting the time-space variations of hydrological processes and the relationships between land use/cover change and surface runoff variation.

关键词： hydrological process, nonlinearity, time-variant gain model, distributed hydrological model.

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Origin of the Red earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science China earth sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2. JI Junfeg3. WANG Xiaoyong1,7, ZHAO Jingbo4, HUANG Baochun5 & LI Zhen6 1. SKLLQG, Institute of earth Environment, Chinese Academy of sciences, Xi’an 710075, China 2. Department of Urban and {2. sciences, Nanjing university, Nanjing 2.0093. China 3. Department of earth sciences, Nanjing university, Nanjing 2.0093. China 4. Department of Geography, Shaanxi Normal university, Xi’an 710062. China 5. Institute of Geology and Geophysics, Chinese Academy of sciences, beijing 10002., China 6 Department of Geography, Qinghai Normal university, Xining 810008, China 7. Graduate School of the Chinese Academy of sciences, beijing 10003., China 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate School of the Chinese Academy of sciences Beijing 100039 China 2. Department of Urban and resources sciences Nanjing University Nanjing 210093 China 3. Department of earth sciences Nanjing University Nanjing 210093 China 4. Department of Geography Shaanxi Normal University Xi’an 710062 China 5. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. Department of Geography Qinghai Normal University Xining 810008 China

The Red earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red earth sequenceconsists of 2. visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the ChineseLoess Plateau. Grain-size analysis shows that the Red earth deposit is very fine-grained with anegligible sand fraction ( > 63.μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63.μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red earth *** REE distributions of the loess-soil and the Red earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the Redearth deposition predates 11.4 Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

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Cenozoic Volcanism in South China Sea and Its Vicinity and South China Sea Spreading

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Journal of China university of geosciences 2002年第3期13卷 217-224页

作者： Zhao Hailing Deng Jinfu Li Kaiming Di Yongjun Yu Junji Zhao Jianhua Li Yonghua faculty of earth {2. and {3. resources, China university of geosciences, beijing 100083 faculty of earth {2. and {3. resources China University of Geosciences Beijing 100083

The rock series, rock types and Sr-Nd isotopic dating of the Cenozoicvolcanic rocks in the South China Sea are similar to those in its vicinity. On the basis of thespreading age of the South China Sea, the Cenozoic volcanic rocks are divided into three stages: thepre-spreading stage, the spreading stage and the post-spreading stage. The deep processcharacteristics of the asthenosphere and lithosphere may be inferred from the study on primarybasaltic magma. The top layers of the asthenosphere both in the spreading stage and in thepre-spreading stage are closer to the earth surface than that in the post-spreading stage. From thepre-spreading stage to the spreading stage, the top layer of the asthenosphere decreased in depth,while the amount of interstitial partial melts increased. The evolution of the primary basalticmagma shows a progressive evolution sequence of the rifting volcanism and a faster lithosphericspreading velocity. From the spreading stage to the post-spreading stage, the top layer of theasthenosphere gradually increased in depth, but the amount of interstitial partial melts *** evolution of primary basaltic magma shows a retrogressive evolution sequence of the riftingvolcanism and a gradual decrease in the lithospheric spreading velocity. The depth recognized by thestudy on the Cenozoic volcanism demonstrates the deep environment for the formation and evolutionof the South China Sea.

关键词： cenozoic volcanism south china sea spreading asthenosphere lithosphere vicinity

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