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Behavioral Diversity and Complexity Indicated by Metazoan Traces at a Topological Level since Proterozoic

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Journal of Earth Science 2000年第3期19卷 118-124页

作者： Gong Yiming Faculty of Earth Sciences, china university of {2., wuhan 430074, china

On the basis of topological criteria, metazoan traces can be classified as four ichnoorders (clusters) and twenty two ichnofamilies (kinds), which consist of nine basic and three combined topological configurations. At a topological level, the behavioral diversity and complexity indicated by metazoan traces have remained quite stable since the Early Cambrian. Dramatic changes of these traits took place in the Neoproterozoic, in which 75% (12.16) of the topoichnotaxa and all nine basic topological configurations of metazoan traces occurred, but the most complex and highest level topological configuration occurred in the Early Cambrian of the coelomate animal explosive evolution, showing that in the Neoproterozoic and Early Cambrian gestated not only the Ediacarian fauna and all the basic types of multi cellular animals known today, but also all the basic and the most complex metazoan traces through geological time.

关键词： metazoan trace topological configuration Proterozoic.

Water in peridotite xenoliths from South china

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Science china Earth Sciences 2011年第10期54卷 1511-1522页

作者： WANG Rong 1,2.3 & ZHANG BaoMin 3 1 Faculty of Land Resource Engineering, Kunming university of Science and Technology, Kunming 650093, china 2.State Key Laboratory for Mineral Deposits Research, Nanjing university, Nanjing 2.0093, china 3 Faculty of Earth Science, china university of geosciences, wuhan 430074, china 1. Faculty of Land Resource Engineering Kunming University of Science and Technology Kunming 650093 China2. State Key Laboratory for Mineral Deposits Research Nanjing University Nanjing 210093 China3. Faculty of Earth Science China University of Geosciences Wuhan 430074 China

The water contents of nominally anhydrous clinopyroxene （cpx）, orthopyroxene （opx） and olivine （ol） in peridotite xenoliths hosted by Cenozoic basalts from Yingfengling, Zhangchouchun, Fujitian and Lindi, South china, were measured by Micro- FTIR. All cpx and opx grains contained a certain amount of water, which was indicated by the presence of hydroxyls in the crystal structure. The water contents （H2., ppm） of cpx and opx from peridotite xenoliths of the study areas were 2.3-981, 183-752. 73-586 and 51-42. ppm, and 82.471, 74-571, 53-170 and 9-135 ppm, respectively. No prominent OH absorption bands were detected for any ol grains, indicating that the water contents were below the detection limit （approximately 2.ppm）. The entire rock contents recalculated according to mineral volume proportions were 49-163, 48-168, 2.-111 and 8-40 ppm, respectively. Combined with previously reported data describing the water contents of peridotite xenoliths worldwide, the results presented here suggest that water distribution in the continental lithospheric mantle is spatially heterogeneous at a global scale. The lithospheric mantle of South china is much richer in water than that of the North china Craton, and is close to that typical of off-craton localities, such as the Basin and Range Province, and Massif Central.

关键词： FTIR water peridotite xenoliths South china

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 Mineral Resources, china university of {2., wuhan 430074, china 2. Institute of Resources & Environments, Henan Polytechnic university, Jiaozuo 454003, china 3. Department of Computer Science, South-Central university for Nationalities, wuhan 430074, china 4. Laboratory of Marine Geology, Tongji university, Shanghai 2.0092. china Faculty of Earth Science and State Key Laboratory of Geological Processes and Mineral Resources china university of {2. wuhan china Institute of Resources & Environments Henan Polytechnic university Jiaozuo china Department of Computer Science South-Central university for Nationalities wuhan{2. Laboratory of Marine Geology Tongji university Shanghai china

Studies show positive shifts of inorganic and organic carbon isotope values (δ 13Ccarb and δ 13Ckerogen) from +0.43 (‰ V-PDB) to +3.54 (‰ V-PDB) and from ?2..38 (‰ 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.

The Characteristics of the Bottom Boundary(T11) of Late Cretaceous Yaojia Formation in Songliao Basin and Its Dynamic Background

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地学前缘 2009年第S1期16卷 173-174页

作者： Ying Song~1,Jianye Ren~2.1.Faculty of Earth Resources,china university of {2.,wuhan 430074,china. 2.Structural Research Center of Oil & Gas Bearing Basin,Ministry of Education,Branch Center in china university of {2.,wuhan 430074,china

Well-preserved Cretaceous lacustrine deposits in Songliao Basin NE china provide a unique opportunity both for building the terrestrial type stage of Cretaceous in china and for studying the response of Cretaceous maj... 详细信息

关键词： Songliao Basin T11 boundary tectonic inversion responding surface tectonic revolution

Analysis on the long term discharge of a catchment

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Journal of Environmental Sciences 2000年第3期12卷 279-285页

作者： HONG Lin 1, TAKASE Keiji 2. SATO Koichi 2.(1. wuhan university of Hydraulic and Electric Engineering, wuhan 430072. china 2. Ehime university, Japan) wuhan university of Hydraulic and Electric Engineering Wuhan 430072 China Ehime university Japan

In this study, the characteristics of the long term discharge of a Terraced Paddy Field Catchment are studied. 2.Kind of Tank Models are proposed and used to simulate the discharge of the catchment. The characteristics of the model simulations of the discharge of the catchment are analyzed and compared with those of a forest catchment.

关键词： long term discharge model simulation terraced paddy field catchment

Nb/Ta variations of mafic volcanics on the Archean- Proterozoic boundary: Implications for the Nb/Ta imbalance

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Science china Earth Sciences 2005年第8期48卷 1106-1119页

作者： LIU Yongsheng1,2. GAO Shan1,2. WANG Xuance1, HU Shenghong1 & WANG Jianqi2.1. State Key Laboratory of Geological Processes and Mineral Resources, china university of {2., wuhan 430074, china 2. Key Laboratory of Continental Dynamics, Department of Geology, Northwest university, Xi’an 710069, china 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences 430074 Wuhan China 2. Key Laboratory of Continental Dynamics Department of Geology Northwest University 710069 Xi’an China

The HFSE and REE of the Precambrian mafic volcanics from the North china craton demonstrate obvious A(Archean)-P(Proterozoic) boundary. The Neoarchean mafic vol- canics show weak correlation between HFSE and TiO2. Their superchondritic Nb/Ta ratio (18.8±1.2. could be attributed to partial melting of mantle peridotite in the presence of garnet. Compared with Neoarchean mafic volcanics, the Paleoproterozoic ones have higher HFSE contents and lower Nb/Ta ratio (15.6±2.9). The significantly elevated HFSE and REE contents of Paleoproterozoic mafic volcanics imply metasomatic enrichment of mantle source, in which Ti-rich silicates could be present as suggested by significant positive correlations between TiO2.and HFSE. The global database of Precambrian mafic volcanics shows a similar A-P boundary. 2. Archean mafic volcanic suites yield an average Nb/Ta ratio of 17.8±1.9 higher than or close to the PM value; Proterozoic mafic volcanics from 2. suites yield an average Nb/Ta ratio of 14.7±4.1 close to the bulk continental crust (BCC) value (11―17.5). Thus, we suggest that the Nb/Ta deficit could be mainly formed in post-Archean time. Archean mafic volcanics could be one of the geochemical reservoirs complementing the low Nb/Ta of the post-Archean continental crust and DM.

关键词： Precambrian mafic volcanics, Nb/Ta deficit, Archean-Proterozoic boundary.

SHRIMP Zircon U-Pb Ages and Geochemical Characteristics of the Neoproterozoic Granitoids in the Huangling Anticline and Its Tectonic Setting

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Journal of Earth Science 2012年第5期23卷 659-675页

作者：魏运许彭松柏蒋幸福彭中勤彭练红李志宏周鹏曾雄伟 wuhan Institute of Geology and Minerals Resources Wuhan Center of Geological Survey Faculty of Earth Sciences China University of Geosciences Three Gorges Research Center for Geo-hazard Ministry of EducationChina University of Geosciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences

SHRIMP zircon U-Pb dating of the Neoproterozoic Maoping （茅坪） series （Sandouping （三斗坪） rock suite） granites exposed in the southern part of the Huangling （黄陵） anticline shows that the formation time of Sandouping biotite-hornblende tonalite intrusion, Jinpansi （金盘寺） hornblende-biotite tonalite intrusion, and Longtanping （龙潭坪） monzogranite are 863±9, 842.10, and 844±10 Ma, respectively. Their geochemical features include A/CNK=0.98-1.06, from metaluminous to weakly peraluminous, δ=1.37-1.53, Sm/Nd=0.17-0.2., and RbN/YbN=1.1-3.62. These indicate that the granite rocks are supersaturated SiO2.calc-alkaline granitoids. The characteristic of Sr-Nd isotopic composition is that the values of εNd（t） and εsr（t） are -12.4 to -11.0 and 2..2.32.2. respectively. It also suggests that the material source of the granite rocks mainly originated from the crust, and they formed in a volcanic arc tectonic environment. These facts suggest that the occurrence of Neoproterozoic granitoids in the southern part of the Huangling anticline should be related to an arc environment along an active continental margin caused by southward subduction of oceanic crust beneath the northern Yangtze craton, and the formation age is not later than 863 Ma.

关键词： Huangling anticline Yangtze plate Neoproterozoic granitoid SHRIMP zircon U-Pbdating geochemistry tectonic setting.

The Magma-dynamic Mechaism of Emplacement and Compositional Zonation of the Zhoukoudian Stock, Beijing

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Acta Geologica Sinica(English Edition) 1989年第2期63卷 159-173,210-211页

作者： Ma Changqian china university of {2., wuhan, Hubei china university of {2. Wuhan Hubei

The Zhoukoudian stock in Beijing is a concentric zoned complex intrusive body formed by two successive intrusions. Quartz-diorite formed by the first intrusion is scattered sparsely on the margins of the body, while granodiorite resulting from the second intrusion constitutes the main part of the intrusion. It exhibits three distinct petrographic zones macroscopically, and is chemically characterized by enrichment of high-temperature components, such as Mg, Ca, Sc, Ti, Cr, Mn. Fe and Co, on its border and merely slight enrichment of some low-temperature components, such as Na and Si, in its central part. A series of structural features indicate that the deformation of the intrusion and thermo-metamorphic rocks becomes weaker with an increase of distance from the contact, and that the intrusive body is a product of ballooning or inflating diapiric emplacement. Based on calculations of the density, viscosity and yield strength of magma and the reasonable diffusion constants and oxygen isotopic data, the mechanism of the compositional zonation of the major part of the stock is discussed. It is considered that the Soret effect, combined with double-diffusive convection, can explain the compositional zonation of the intrusion. Calculation of the ascent rates of magma shows that successive upwelling of magma got faster and faster with the progress of time.

关键词： The Magma-dynamic Mechaism of Emplacement and Compositional Zonation of the Zhoukoudian Stock Beijing

LA-ICP-MS U-Pb Zircon Geochronology,Geochemistry and Kinetics of Wenquan Ore-Bearing Granites from Western Qinling,china

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矿物学报 2009年第S1期29卷 298-300页

作者： CAO Xiao-feng1,2.Lü Xin-biao1,2.CHEN Chao2.LIU Shen-tai2.ZHANG Ping2.SU Yu-yun2.MEI Wei2.ZHANG Bin3(1. State Key Laboratory of Geological Processes and Mineral Resources,china university of {2.,wuhan 430074,china 2. china Resource Department,china university of {2.,wuhan 430074,china)

As we know there is a famous East Qinling-Dabie molybdenum belt in china,where many molybdenum deposits located such as super giant Jinduicheng,Sandaozhuang,Shangfanggou and Nannihu molybdenum deposits(Li,2.08) ;The molybdenum mineralization in the East Qinling-Dabie belt clusters into three groups or mineralization pulses:2.3-2.1,148-138 and 131-112.Ma(Mao et al,2.08).

关键词： Pb LA-ICP-MS U-Pb Zircon Geochronology,Geochemistry and Kinetics of Wenquan Ore-Bearing Granites from Western Qinling,china ICP MS