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Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils

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Science China earth sciences 2005年第10期48卷 1656-1665页

作者： GONG Yiming1,2. XU Ran1, TANG Zhongdao1, SI Yuanlan3.& LI Baohua4 1. faculty of earth Science and State Key Laboratory of Geological Processes and {2. resources, China university of geosciences, Wuhan 43.074, China 2. Institute of resources & Environments, Henan Polytechnic university, Jiaozuo 454003. China 3. Department of Computer Science, South-Central university for Nationalities, Wuhan 43.074, China 4. Laboratory of Marine Geology, Tongji university, Shanghai 2.0092. China faculty of earth Science and State Key Laboratory of Geological Processes and {2. {3. China university of geosciences Wuhan China Institute of resources & Environments Henan Polytechnic university Jiaozuo China Department of Computer Science South-Central university for Nationalities Wuhan China Laboratory of Marine Geology Tongji university Shanghai China

Studies show positive shifts of inorganic and organic carbon isotope values (δ 13.carb and δ 13.kerogen) from +0.43.(‰ V-PDB) to +3.54 (‰ V-PDB) and from ?2..3. (‰ V-PDB) to ?2..14 (‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2.3.X 15%)) values from 0.015 to 0.144, TOC values from 0.02. to 0.2.%, V/Cr values from 0.3.to 2.0, Sr/Ba values from 3.2. to 49.50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, South China, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2. climatic cooling and sea level falling c

关键词： mass extinction, bacteria-algae, carbon isotopes, molecular fossils, biodiversity, Late Devonian, Guangxi, South China.

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Charnockite Formation and Early Precambrian Crust Evolution in Yishui Area, Shandong Province, China

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Journal of earth Science 2000年第3期19卷 147-151页

作者： Su Shangguo Zhou Xunruo Gu Deling Hu Ling faculty of earth {2. and {3. resources, China university of geosciences, beijing 100083. China

Charnockite and granulite in Yishui area, Shandong Province are located in the middle part of the Tancheng Lujiang fault zone, eastern China. Field studies have shown that the charnockites, derived from the adjacent granulites, are classified as three types: enderbite, garnet enderbite and hypersthene trondhjemite. In addition, two generations of minerals are present in the charnockites: the relic minerals such as garnet, hypersthene and clinopyroxene, and the neocrystallized minerals such as plagioclase and K feldspar. The relic minerals occurring in the granulite facies stage were affected by the later partial melting. The relic minerals, irregular and usually ragged in shape, occupy the interstitial positions in the neocrystalline minerals. The neocrystalline minerals are usually euhedral subhedral crystals. The study of petrology, mineralogy and geochemistry of charnokites concludes that the enderbite was formed by the anatexis of the two pyroxene plagioclase granulite, that the garnet enderbite was formed by the anatexis of sillimanite garnet gneiss, and that the hypersthene trondhjemite was formed by the anatexis of the leucocratic two pyroxene plagioclase granulite. The U Pb dating of the zircon indicates that the formation of the charnockite and granulite was related to the Archean Proterozoic upwelling of a mantle plume (hot spot) around 2.500 Ma, in Yishui area, Shandong Province.

关键词： charnockite Early Precambrian crust evolution mantle plume Yishui area.

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Ore-forming Response to Syndepositional Submarine Volcanism in Langshan-Zhaertai Mesoproterozoic SEDEX Ore Belt, Inner Mongolia, China

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Journal of earth Science 2000年第3期19卷 108-113页

作者： Peng Runmin Zhai Yusheng Deng Jun Xiao Rongge Wang Jianping faculty of earth {2. and {3. resources, China university of geosciences, beijing 100083. China

Ore forming process of the Dongshengmiao, Huogeqi, Tanyaokou and Jiashengpan deposits in Langshan Zhaertai Mesoproterozoic SEDEX metallogenic belt is closely related to the syndepositional volcanic activities based on the following facts: (1) The Sm Nd isochron age of the basic volcanic rocks varies from 1 491 Ma to 1 82. Ma (more than or close to the model age of the lead isotope of all sulfide minerals) in these deposits, with ε (Nd, t ) =(3.48-6.40)±0.80, whose REE composition is enriched in LREE and depleted in HREE, indicating that these volcanic rocks were derived from the mantle or lower crust. (2. The REE composition of some Pb Zn Py ores is also enriched in LREE and depleted in HREE. The chondrite normalized REE patterns are similar to those of the basic volcanic rocks. (3. In the lead isotope composition diagram of Doe and Zartman, most of sphalerite, galena, pyrite, pyrrhotite and chalcopyrite are plotted on both sides of the line for the mantle or between the lines for the mantle and lower crust. (4) Cobalt content of some pyrites is much higher than their nickel content ( w (Co)/ w (Ni)= 11.91- 12.19). (5) Some volcanic blocks and debrises have been picked out from some pyrite and pyrrhotite ores. (6) All Zn Pb Cu Fe sulfide orebodies in these deposits occur in the strata overlying the metamorphic volcanic rocks in the only second ore bearing formation. The Jiashengpan deposit lacks in syndepositional volcanic rocks in the host succession, only Pb and Zn occur without Cu, but the Dongshengmiao, Tanyaokou and Huogeqi deposits with syndepositonal volcanic rocks in the host succession contain Cu, indicating the relatively high ore forming temperatures, besides Pb and Zn. The syndepositional volcanic eruption directly supplied some ore forming metals and resulted in the secular geothermal anomaly favorable for the circulation of the submarine convective hydrothermal system, and in the precipitation of deep mineralizing fluids exh

关键词： volcanic activities ore forming response SEDEX deposit Mesoproterozoic Inner Mongolia.

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Incised valley filling deposits:an important pathway system for long-distance hydrocarbon migration—a case study of the Fulaerji Oilfield in the Songliao Basin

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Petroleum Science 2009年第3期6卷 230-238页

作者： Xin Renchen Liu Hao Li Guifan School of Ocean sciences China University of Geosciences Beijing 100083 China School of the earth sciences and {2. China University of Geosciences Beijing 100083 China

In this paper, incised valley filling deposits, which formed an important pathway system for long-distance hydrocarbon migration, are discussed in detail based on core and logging data. The sequence SQy2. of the Cretaceous Yaojia Formation is the main hydrocarbon-bearing layer in the Fulaerji Oilfield. The hydrocarbon source of the oilfield is the Qijia-Gulong Sag which is about 80 km away from the Fulaerji Oilfield. The transport layer of long-distance hydrocarbon migration is the overlapped sandstone complex which fills the incised valley. The incised valley developed during the depositional period from the late Qingshankou Formation to the early Yaojia Formation of Cretaceous （SQqna-SQy0 was about 70 km long and 2. km wide, and extended in the NW-SE direction. The overlapped filling of the incised valley mainly occurred in the expanding system tract of the third-order sequence SQy2. （ESTy2.）. Towards the basin, incised valley filling deposits overlapped on the delta developed in the early period, and towards the basin margin, incised valley filling deposits were covered by the shore-shallow lacustrine sandy beach bar developed in the maximum flooding period. All of the delta, the incised valley filling and the shore-shallow sandy beach bar are sandstone-rich, and have high porosity and permeability, and can form an effective hydrocarbon migration and accumulation system. Deltaic sand bodies collected and pumped hydrocarbon from the active source, incised valley filling depositional system completed the long-distance hydrocarbon migration, and lithological traps of shore-shallow lacustrine sandy beach bar accumulated hydrocarbon. The incised valley filling sequences are multi-cycle： an integrated shortterm filling cycle was developed on the erosion surface, and the sequences upward were mud-gravel stone, medium-fine sandstone containing terrigenous gravels and muddy pebbles with cross bedding, silty mudstone with ripple bedding, and mudstone. The incised valley fi

关键词： Songliao Basin Fulaerji Oilfield Yaojia Formation incised valley filling migration pathway system

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Zircon and apatite fission track analyses on mineralization ages and tectonic activities of Tuwu-Yandong porphyry copper deposit in northern Xinjiang, China

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Science China earth sciences 2007年第12期50卷 1787-1795页

作者： YUAN WanMing1,BAO ZengKuan2.DONG JinQuan2.GUO ZhaoJie3.& DENG Jun1 1 State Key Laboratory of Geological Processes and mineral {3.,China {2. of geosciences,beijing100083.China 2.Laboratory of Nuclear Analysis Techniques,Institute of High Energy Physics,Chinese Academy of sciences,beijing 10003.,China 3.Department of Geology,Peking {2.,beijing 100871,China 1. State Key Laboratory of Geological Processes and mineral resources China University of Geosciences Beijing 100083 China 2. Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China 3. Department of Geology Peking University Beijing 100871 China

The mineralization ages reported in the past in the Tuwu-Yandong copper district not only are different,but also fall into the Hercynian *** study has achieved 9 zircon and 7 apatite fission track analysis *** zircon fission track ages range from 158 Ma to 2.9 Ma and the apatite ages are between 64 Ma and 140 *** mineralization accords with the regional tectonics in the copper *** consider that the zircon fission track age could reveal the mineralization age based on annealing zone temperature of 140―3.0℃ and retention temperature of ～2.0℃ for zircon fission track,and metallogenetic temperature of 12.―3.0℃ in this ore *** three mineralization epochs have been identified,i.e.,2.9―2.6 Ma,2.2.2.0 Ma and 165―158 Ma,and indicate occurrence of the min-eralization in the Indosinian and Yanshan *** to apatite fission track ages,the three tectonic-mineralizing epochs are 140―13.1}Ma,109―97 Ma and 64 Ma,which means age at about 100℃ after the *** three epochs lasted 146 Ma,108 Ma and about 100 Ma from ～2.0℃ to ～100℃ and trend decrease from early to *** is shown by the fission track modeling that this district underwent three stages of geological thermal histories,stable in Cretaceous and cooling both before Cretaceous and after 2. Ma.

关键词： mineralization age, tectonic epoch, fission track, zircon, apatite, Tuwu-Yandong, Xinjiang

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The Status of Organochlorine Pesticides Pollution in Hubei Section of the Yangtze River

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地学前缘 2009年第S1期16卷 81-82页

作者： Chen Liu,Liyuan Guo School of the earth sciences and {2.,China {3. of geosciences(beijing),beijing 100083.China.

The Organochlorine Pesticides(OCPs),such as hexachlorocyclohexane(HCH)and dichlorodiphenyltrichloro ethane(DDT),are well known as typical persistent organic pollutions(POPs).They were worldwide used several decades ago,even today in some *** the water resource is very important in natural environments and essential to agriculture,the pollution of OCPs in water has emerged as worldwide environmental problem. Wuhan section of the Yangtze River is the drinking water source of Wuhan area in Hubei *** addition,Hubei province is an important production base of grain,cotton,oil and *** the rapid development of industry and mass-use of OCPs

关键词： organochlorine pesticides Yangtze River water residues

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A new iguanodontid (Jin-zhousaurus yangi *** ***.) from the Yixian Formation of western Liaoning,China

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Chinese Science Bulletin 2001年第19期46卷 1669-1672页

作者： WANG Xiaolin & XU Xing1. Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of sciences, beijing 100044, China 2. College of {2. sciences and resources, China university of Geo-sciences, beijing 100083. China Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China College of earth sciences and {2. China University of Geosciences Beijing China

A new iguanodontid, Jinzhousaurus yangi gen. et sp. nov., is erected based on the cranial and dental morphology of a specimen from the Yixian Formation of western Liaoning. Although a few primitive characteristics remain, Jinzhousaurus yangi display a number of characteristics similar to those seen in derived iguanodontids. Other interesting characteristics include the absence of antorbital fenestra and the frontal excluded from the participation in orbit, which are closer to the condition in hadrosaurids. The unusual combination of the characteristics provides important data for assessing morphological evolution toward hadrosaurs. The new discovery also represents the first reported large-sized dinosaur from Jehol fauna in western Liaoning, and increases the diversity of this famous fauna. Furthermore, the discovery of a derived iguanodontid from the Yixian Formation provides further evidence supporting a Cretaceous age of the Jehol fauna, which is consistent with an isotopic age.

关键词： Western Liaoning Lower Cretaceous Yixian Formation Jehol Biota Iguanodontid

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Evolution　of　Circum－Pacific　Basins　andVolcanic　Belts　in　East　China　and　Their　Geodynamic　Background

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Journal of earth Science 1995年第1期14卷 48-58页

作者： Li Sitian(faculty of earth {2., China {3. of geosciences, Wuhan 43.074)Mo Xuanxue(Department of Geology and mineral {2., China {3. of geosciences, beijing 100083.)Yang Shigong(faculty of earth {2., China {3. of Geosc

Based upon the recent research on the Circum- Pacific geology and sedimentary basins a review of the time - space evolution of Mesozoic and Cenozoic basic and their geodynamic background are outlined. The foreland-type basins originated mainly in Late Triassic during the convergence of East Tethys and the continental collision, while the extensional and transform-extensional basins formed mainly in the Eastern China in Late Mesozoic and Cenozoic. They are closely related to the subduction Process of Pacific Plate from eat and the collision from southwest. As a sighficat indicator of deep Process of the earth, the igneous rocks and magmatism offer very important information for the basin dynamic analysis. The evolution of the basins in East China were controlled by the combination and alternation effects from the surrounding Plates of Eurasia and the deep Process.

关键词： Cirum-Pacific basins magmatism geodynamics.

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TECC Applied in Geopark for a Case Study of Qixia Planning National Geopark

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地学前缘 2009年第S1期16卷 295-296页

作者： Feifei Hu,Mingzhong Tian School of the earth sciences and {2.,China {3. of geosciences(beijing),beijing 100083.China.

This paper applied the theory of TECC(Tourism Environmental Carrying Capacity) into the case of Qixia Planning National *** adopt new planning framework to do the planning of TECC。

关键词： TECC geoheritages basic environment Qixia Planning National Geopark

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Issues on China Regional Metallogeny

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Journal of earth Science 2000年第3期19卷 26-33页

作者： Zhai Yusheng Deng Jun Peng Runmin faculty of earth {2. and {3. resources, China university of Geosciencs, beijing 100083. China

According to geotectonic evolution and regional lithospheric features, the authors proposed six metallogenic domains in China: (1) Tianshan Xingmeng metallogenic domain, (2. Tarim North China metallogenic domain, (3. Qinling Qilian Kunlun metallogenic domain, (4) Yangtze metallogenic domain, (5) South China metallogenic domain and (6) Himalaya Sanjiang metallogenic domain. In this paper, the authors also discuss, on the bases of geotectonic background and metallogenic evolutionary history, some metallogenic features of China: (1) A large percentage of ore formation occurred in paleo continental margins, including continental marginal rift and continental marginal accretionary orogenic belt. The majority of main mineral deposits are discovered on continental margins. (2. Superimposition of mineralization, favored the building up of giant and large mineral deposits, but often made the mineral deposits more complex in composition (associated components), morphology and structure. (3. mineralization of crust derived anatectic granite is intensive and especially concentrated in the South China metallogenic domain. mineralizations, including W, Sn and REE, are the products of long and mature development of W Sn polymetal rich earth crust in the metamorphic basement of South China Caledonian fold belt. (4) Epithermal ore forming system is well developed in the southwest part of Yangtze continental block. Ore deposits of Hg, Sb, As, Au, Ag and U densely occur in sedimentary strata of the Late Paleozoic to Triassic. Ge, Tl, Te can also constitute independent ore deposits. (5) Ore formation caused by tectonic dynamic activities is distinctive. Small scale continental blocks of China display intensive activities, which played a widespread and diverse role in ore control. Junctions of faults, synchronous faults, shear zone structure and metamorphic core complex are main ore control structures. (6) The gold mineralization is complex and diversified. The greenstone

关键词： metallogenic domain metallogenic feature composite continental metallogenic system China.

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