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The species diversity of fusulinaceans and high-frequency sea-level changes in the Carboniferous-Permian boundary section at Xikou, Zhen'an County,Shaanxi Province, China

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Science China Earth Sciences 2006年第7期49卷 673-683页

作者： ZHANG Haijun1, WANG Xunlian2. DING Lin1, XIA Guoying3 & WANG Lei2.1. Institute of Tibetan Plateau Research, Chinese Academy of Sciences, beijing 100085, China 2. Faculty of Earth Sciences and Mineral Resources, China university of {2., beijing 100083. China 3. Tianjin Institute of Geology and Mineral Resources, Tianjin 300170, China 1. Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 2. Faculty of Earth Sciences and Mineral Resources China University of Geosciences Beijing 100083 China 3. Tianjin Institute of Geology and Mineral Resources Tianjin 300170 China

The study on the interrelation between sea-level changes and biodiversity with its evolu-tion has great significance for understanding the impact of global changes on organic evolution and exploring the inherent laws of life-environment coevolution in geological history. In this paper, the stratigraphic distribution of fusulinacean fauna in the Carboniferous-Permian boundary section at Xikou, Zhen’an County, Shaanxi Province, is analyzed quantitatively, and the relationship between the species diversity of fusulinaceans and relative sea-level changes is discussed. As a whole, the spe-cies numbers of fusulinacean fauna experience a rapid increase and an obvious decline in Xikou, Zhen’an County, from the Late Carboniferous to the Early Permian. There is a significant increase in species diversity around the Carboniferous-Permian boundary, which is one of the biggest bio-events of the fusulinacean fauna, and represents the radiation of Pseudoschwagerininae subfamily in the studied area. Integrated fusulinacean species diversity into sequence stratigraphic framework, de-tailed study suggests that the species diversity of the fusulinaceans is closely related to its relative stratigraphic location, and is essentially controlled by the sea-level changes, especially by the high-frequency sea-level changes. Generally, the species diversity of fusulinaceans is low, and the number of first and last appearance datum is small in the lower unit of high-frequency depositional cycle formed during the quick rise of the sea level; whereas the species diversity of fusulinaceans is high, and the number of first and last appearance datum is large in the upper unit of high-frequency cycle formed during the slow fall of the sea level. Within the third-order depositional sequence, the species diversity of the fusulinaceans at the first flooding surfaces and the maximum flooding surfaces is low, and it increases upward. The fusulinacean species diversity is low within the transgressive syst

关键词： fusulinaceans, species diversity, high-frequency cyclothem, sequence stratigraphy, sea-level changes, Carboniferous-Permian boundary, Zhen'an, Shaanxi.

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Experimental remolding on the caprock's 3D strain field of the Indosinian-Yanshanian epoch in Tongling deposit concentrating area

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Science China Earth Sciences 2005年第7期48卷 863-874页

作者： DENG Jun1,HUANG Dinghua2.WANG Qingfei1,WAN Li1,SUN Zhongshi3,YANG Liqiang1 & GAO Bangfei1 1. State Key laboratory of geological Processes and Mineral Resources,China {2. of geosciences,beijing 100083.China 2. Faculty of Earth Sciences,China {2. of geosciences,Wuhan 430074,China 3. Department of Earth Sciences,Jilin {2.,Changchun 130061,China State Key laboratory of geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China Department of Earth Sciences Jilin University Changchun 130061 China

Based on field observations and rheology analysis, we perform one analogue experiment and remold the 3D structural frame of Tongling deposit concentrating area firstly. Then we disassemble and dialyze the 3D structures of the model using the methods of "slicing" and "stripping". A series of sliced planes vertical to the fold hinges show similar landscapes of that in the drill hole profiles. Meanwhile, layer stripping analysis indicates that the deformation features of each layer in the model are qualitatively analogical to those obtained from field observations. Through contrasting the 3D structure between the experimental model and the field phenomena, we verify the following 3D deformation features of the caprock in this area: (1) the Tongling area mainly consists of three series of NE S-typed fold groups; (2. in the uniform stress field, the incoherent folds universally develop in different positions, along different axes as well as in different strata; (3) the faults propagate upward which are mostly inter-bedded detachment faults, while the fold amplitudes decrease while going deeper; and (4) the folds and cleavages are highly developed in the Silurian System indicating that the deformation effect of the Indosin-ian-Yanshanian structural layer terminates at this layer, which suggests that the Silurian System is the crucial layer for the inversion between brittle and plastic deformation domains and the underlying strata are subject to the control of another deformation system with distinct properties.

关键词： Tongling deposit concentrating area Indosinian-Yanshanian epoch 3D structural frame of the caprock analogue experiment slicing and stripping analysis structural model.

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Spatio-temporal carbon isotope variation during the Ediacaran period in South China and its impact on bio-evolution

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Science China Earth Sciences 2009年第10期52卷 1520-1528页

作者： WANG XinQiang1 & SHI XiaoYing1,2.1 School of Earth Science and Mineral Resources, China university of geosciences, {2. 100083. China 2.State Key laboratory of geological Processes and Mineral Resources, {2. 100083. China School of Earth Science and Mineral Resources China University of Geosciences Beijing 100083 China State Key laboratory of geological Processes and Mineral Resources Beijing 100083 China

The Ediacaran period is characterized by the extremely negative carbon isotope anomalies and great biotic evolution in Earth history. At least four negative carbon isotope anomalies have been reported from this interval in South China so far. It is traditionally argued that the isotope variations can be used as a useful tool for global correlation of Ediacaran succession; however, more and more researches argued against this idea. We reviewed the previously published carbon isotope data in South China, and distributed the mean values of a certain time to the paleogeographic maps. The results show that the carbon isotope values (δ13C) vary greatly in different environments, but a clear tendency of becoming lighter from shallow platform to deep basin, with a maximum variation up to 1‰ Moreover, the important changes in Ediacaran biota, marked by the introducing of new taxa or ecologic groups, seemed to always postdate the negative anomalies but coincide with the positive shift. If the negative excursions represented the oxidation of a large dissolved organic carbon (DOC) reservoir in the ocean, the diverse Ediacaran organisms and the carbon isotope anomalies may suggest totally different environments: oxic and anoxic/euxinic. We also suggest that the elimination of euxinic state through precipitation of pyrites is one of the important environment factors in prompting the Ediacaran bio-evolution.

关键词： Ediacaran South China carbon isotope spatio-temporal variations bio-evolution

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Wave tectono-sedimentary processes in Tarim basin

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Science China Earth Sciences 2005年第11期48卷 1949-1959页

作者： JIN Zhijun1,2. ZHANG Yiwei1 & CHEN Shuping1 1. Key laboratory for Hydrocarbon Accumulation, Ministry of Education, China university of Petroleum, {2. 102.49, China 2. Exploration and Production Research Institute, China Petroleum & Chemical Corporation, {2. 100083. China 1. Key laboratory for Hydrocarbon Accumulation Ministry of Education China University of Petroleum 102249 Beijing China 2. Exploration and Production Research Institute China Petroleum & Chemical Corporation 100083 Beijing China

Based on the unconformities, the formation times of structures, and geological wave filtering applied to basin fills of typical wells around the Manjiaer area in the Tarim basin, the wave tectono-sedimentary processes in the Tarim Basin are discussed. The results of geological wave filtering of basin fills of typical wells show that, in time domain, the evolution of the Tarim basin was controlled by various wave processes with the periods of 740±Ma, 2.0±Ma, 100±Ma and 30±Ma. The analyses of basin fills, basin subsidence and unconformities show that the trends of the sedimentary facies belts, depocenters, and centers of subsidence migrated and interchanged periodically with periods of 2.0±Ma. These show the propagation of wave movements in space domain. The wave evolution of the Tarim basin is of significance to understanding the formation of the oil and gas reservoirs in the basin.

关键词： Tarim basin, tectonics, sedimentation, crustal undation, wave evolution

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Preliminary notes on soft-bodied fossil concentrations from the Early Cambrian Chengjiang deposits

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Science Bulletin 2006年第20期51卷 2482-2492页

作者： HAN Jian1, SHU Degan1,2. ZHANG Zhifei1, LIU Jianni1, ZHANG Xingliang1 & YAO Yang1 1. Department of Geology and Key laboratory for Continental Dynam- ics, Northwest university, Xi’an 710069, China 2. School of Earth Sciences and Resources, China university of Geo- sciences, beijing 100083. China Department of Geology and Key laboratory for Continental Dynamics Northwest University Xi''an 710069 China School of Earth Sciences and Resources China University of Geo-sciences Beijing 100083 China

The efforts of labor-intensive collecting in the Early Cambrian Chengjiang deposits in eastern Yunnan Province, China led to the discovery of many horizons containing exceptionally well preserved soft-bodied fossil concentrations, many of which can be assigned to either monospecific concentrations or paucispecific concentrations. The features of these fossil concentrations support the hypothesis that frequent storm events producing tempestites mainly contributed to the preservation of abundant soft- bodied fossils in the Chengjiang deposits, and indi- cate that the balance of the ecological web in this region was probably frequently destroyed or upset by such storm events during that geological time. Ani- mals in a fossil assemblage in such fossil concentra- tions probably occupied similar ecological biotopes.

关键词： Early Cambrian Chengjiang fauna preservation soft- bodied fossil concentration (SFC).

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Web GIS design and realization for groundwater resources in the Yellow River basin

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Science China(Technological Sciences) 2004年第z1期47卷 106-117页

作者： GAO Jianguo1,2. GONG Huili1,2. ZHAO Wenji1,2. ZHANG Xiaosong1 & YAN Ning2.1. Resource, Environment and GIS Key laboratory of beijing, Capital Normal {2., beijing 100037, China 2. 3 Dimension Information Extraction and Application Key laboratory of Education Ministry, beijing 100037, China Correspondence should be addressed to Gong Huili Web GIS design and realization for groundwa- ter resources in the Yellow River basin GAO Jianguo1,2. GONG Huili1,2. ZHAO Wenji1,2. ZHANG Xiaosong1 & YAN Ning2.1. Resource, Environment and GIS Key laboratory of beijing, Capital Normal {2., beijing 100037, China 2. 3 Dimension Information Extraction and Application Key laboratory of Education Ministry, beijing 100037, China Capital Normal Univ Resource Environm & GIS Key Lab Beijing Beijing 100037 Peoples R China 3 Dimens Informat Extract & Applicat Key Lab Educ Minist Beijing 100037 Peoples R China

This article brings forward a design and realization scheme of Web GIS in the Yellow River basin for the management of groundwater resources. The main goals are to manage and share data of massive-scale, to support the research of groundwater resources in the Yellow River basin. In this paper we point out the necessity and feasibility of building the distributed Web GIS for geographical research objects on a large scale. We put forward some solutions for the construction of this kind of system including a holistic deployment strategy in the Internet, a scheme of distributed data storage and management, a design of application structure based on three tires architecture by each province and how they collaborate with each other. It also illuminates how the application server works, and sets forth the relations among databases which work together in this system.

关键词： the Yellow River basin, groundwater, Web GIS.

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Petrogenesis and dating of the Kangding complex,Sichuan Province

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Science China Earth Sciences 2005年第5期48卷 622-634页

作者： CHEN Yuelong 1 , LUO Zhaohua 1 , ZHAO Junxiang, LI Zhihong, ZHANG Hongfei & SONG Biao 3 1. Faculty of Earth Sciences and Natural Resources, China university of geosciences, {2. 100083. China 2. Faculty of Earth Sciences, China university of geosciences, Wuhan 430074, China 3. {2. SHRIMP Center, Institute of Geology, Chinese Academy of geological Sciences, {2. 100037, China 1. Faculty of Earth Sciences and Natural Resources China University of Geosciences 100083 Beijing China 2. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China 3. beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China

An analysis of major and trace element geochemistry and SHRIMP U-Pb zircon dating of mafic, intermediate, and felsic rocks from the Mianning metamorphic complex of Si- chuan Province was conducted. One of our conclusions is that a majority of the zircons crystal- lized between 72. and 773 Ma in a magmatic regime. The complexes contain early to late Pa- leo-proterozoic relict zircons from ancient continental crust. The oldest age, 2.68 Ma, may rep- resent the basement of the Yangtze block. Overgrowth zircon rims and palingenetic zircons have been observed and dated, and are believed to have formed after crystallization, during Paleozoic and Mesozoic metamorphic-anatexis. We also conclude that depletion of Nb, Ta, HREE, in a spider-diagram normalized to primitive mantle and calc-alkaline association, implies that they formed in island-arc or under-plating settings.

关键词： Kangding complex, zircons, SHRIMP, tectonic setting.

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A New SHRIMP Age of the Xiamaling Formation in the North China Plate and Its geological Significance

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Acta Geologica Sinica(English Edition) 2007年第6期81卷 1103-1109页

作者： GAO Linzhi~(1,*)ZHANG Chuanheng~2.SHI Xiaoying~2.ZHOU Hongrui~2.WANG Ziqiang~2.SONG Biao~(1,3) 1 Institute of Geology,Chinese Academy of geological Sciences,beijing 100037,China 2.China {2. of geosciences(beijing),beijing 100083.China 3 beijing SHRIMP Central,100037 beijing,China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

Setting up the hypostratotype of late Precambrian is the main aim of the research on the Meso-and Neoproterozoic in North *** chronostratigraphic position is the key in this study. However,many key horizons have not been calibrated with the high-quality isotopic *** the reported new U-Pb age with the Sensitive High-Resolution Ion Microprobe（SHRIMPⅡ）,a zircon U- Pb age was obtained of the ash bed in the Xiamaling Formation in North China Plate,yielding a weighted mean;Pb/;U age of 1368±12.*** is the first SHRIMP U-Pb age from the Xiamaling Formation in the North China Plate,and represents the depositing time of the middle part of the Xiamaling *** zircon age plays an important role to understanding geological evolution of the North China Plate during Meso-and Neoproterozoic.

关键词： SHRIMP U-Pb Dating Mesoproterozoic Xiamaling Formation North China Plate

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Synthesis of 6-(Bromomethyl)-4-methoxy-5,6,7,8-tetrahydropyrido-[3,2.d]pyrimidin-2.ol from 6-Methylpyrimidine-2.4-diol

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Chemical Research in Chinese Universities 2012年第1期28卷 57-60页

作者： LIU Wei-dong2. DENG Xi-ling2. ZHANG Zhi-li2. WANG Xiao-wei2.and LIU Jun-yi1,2.1. State Key laboratory of Natural and Biomimetic Drug, 2. Department of Chemical Biology, School of Pharmaceutical Sciences, Peking university, {2. 100191, P. R. China Peking Univ Sch Pharmaceut Sci State Key Lab Nat & Biomimet Drug Beijing 100191 Peoples R China Peking Univ Sch Pharmaceut Sci Dept Biol Chem Beijing 100191 Peoples R China

6-（Bromomethyl）-4-methoxy-5,6,7,8-tetrahydropyrido[3,2.d]pyrimidin-2.ol（compound 9） was synthe sized from 6-methylpyrimidine-2.4-diol（compound 1） through the crucial steps of 6-methyl alkylating and intramo lecular cyclization. The assignment of the structure of compound 9 was performed by its spectral data, 1H NMR, 13C NMR, HMBC, and HRMS spectra.

关键词： Heterocycle Carbanion Alkylation Reduction Cyclization

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Environmental characteristics of Mid-Holocene recorded by lacustrine sediments from Lake Daihai, north environment sensitive zone, China

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Science China Earth Sciences 2006年第9期49卷 968-981页

作者： SUN Qianli1,2. ZHOU Jie1, SHEN Ji3, CHEN Peng1,2. WU Feng1,2.& XIE Xiuping1,2.1. State Key lab of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 2. Graduate university of Chinese Academy of Sciences, {2. 100039, China 3. Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 2.0008, China 1. State Key lab of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 2. Graduate university of Chinese Academy of Sciences Beijing 100039 China 3. Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

Climate proxies, such as total organic carbon and nitrogen (TOC, TN), carbonate content (CaCO3), grain-size and pollen of the sediment core retrieved from enclosed Lake Daihai which lies in the north China environment sensitive zone are analyzed to reconstruct the environment evolution of the area based on high-resolution radiocarbon chronology. The results reveal that the TOC and TN contents of the sediments correlate well with pollen percentage and pollen flux variations during the Holocene, and both reach their peak values simultaneously at 6.7―3.5 ka BP (calendar age, 7.6―3.6 ka BP). Since 6.7 ka BP, both the CaCO3 and organic matter contents of the core have simultaneous variations, and their high values also occur during 6.7―3.5 ka BP. While during 9.0―6.7 ka BP (calendar age, 10―7.6 ka BP) relatively lower level of organic matter content and pollen flux corre- spond to the higher level of carbonate content. The above relations suggest that during 6.7―3.5 ka BP, the productivity and effective precipitation were greatly improved in the lake drainage area, and this would probably strengthen the hydrodynamic conditions, enhancing organic matter, pollen and carbonate inputs from terrestrial sources. Such processes would account for the enrichment of both organic matter and carbonate in the sediments. While during 9.0―6.7 ka BP, the lower level of or- ganic matter, pollen flux but high carbonate content show depressed productivity and declined vege- tation coverage. The higher carbonate content at this stage would have probably resulted from the higher evaporation ratio of the lake water under relatively drier climate conditions. Therefore, it is in- ferred that during 6.7―3.5 ka BP, the climate was more humid with abundant rainfalls and vegetation was more flourishing in the Lake Daihai area. This can be seen as Holocene Climate Optimum (HCO). As a result, this has evident discrepancies with the traditional notion that the HCO occurs at Early Holocene or early Mid

关键词： Lake Daihai, Mid-Holocene, lacustrine sediments, environmental characteristics.

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