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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 university 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

Simulating the transfer and fate of hexachlorocyclohexane in recent 50 years in beijing, china

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Science china earth {2. 2005年第12期48卷 2203-2213页

作者： CAO Hongying1, LIANG Tao1 & TAO Shu2.1. Institute of geographical sciences and Natural {2. Research, Chinese Academy of sciences, beijing 100101, china 2. Laboratory for earth Surface Processes, Peking university, beijing 100871, china 1. Institute of geographical sciences and Natural {2. Research Chinese Academy of Sciences 100101 Beijing China 2. Laboratory for earth Surface Processes Peking University 100871 Beijing China

Taking beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 1952.2.03 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1952.1983, the average input and output amount of HCHs through agricultural application and degradation are 130 t and 150 t respectively. The dominant transfer processes of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these processes are 80 t?a?1, 16 t?a?1 and 11 t?a?1, which account for 92. of total transfer fluxes of HCHs isomers. There were approximately 2.3t HCHs in all environmental compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1984 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5% that before 1983, and this percentage may descend to 0.5% after 2. years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.

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 university 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 [?]3Mei Mingxiang Male born in 1965 got his Ph.D. in geology at the china {2. 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 3300-m-thick carbonate strata formed in a period of about 100 Ma (1310±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

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 university 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

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 {2. 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, {2. university of geosciences, beijing 100083. china 2.State Key Laboratory of geological Processes and Mineral resources, beijing 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

Problems of Sequence Stratigraphy in china

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Journal of earth Science 2000年第3期19卷 10-20页

作者： Wang Hongzhen Faculty of earth sciences and Mineral {2., china university of geosciences, beijing 100083. china

A comprehensive study of outcrop sequence stratigraphy in china began in the early 1990s. The investigated strata range from Mesoproterozoic to Quaternary and the studied areas cover the three platforms and margins, the Southern Himalayas and the East china and South china seas. Problems of general concern in the sequence stratigraphy of china are discussed. These are: the hierarchy for sequence stratigraphy, the third order Sequence and eustasy, the chronostratigraphic boundaries and GSSP, and the International Stratigraphic Chart and the sequence chronostratigraphy of china. The average time interval of Mesosequence (2.-40 Ma) and of the Sequence (2.5 Ma) is suggested and the minor sequences below the Sequence are discussed. The time interval of the Sequence shows no evident decrease with time, but several epochs with remarkable short intervals occur in the Phanerozoic, which may represent a planetary behavior denoting the special development stages in earth’s evolution. Sea level change curves are given separately for the three platforms and the different regions. The Global Stratotype Section and Point (GSSP) concept and practice are discussed, and a comparison between the first appearance point of biozone and the first flooding surface in the Sequence is made for designation of the chronostratigraphic boundary. It is suggested that the chronostratigraphic boundaries might be set at the first flooding surface in the Sequence for easy recognition. The idea of sequence chronostratigraphy is recommended, and a comparison between the International Stratigraphic Chart and the sequence chronostratigraphy of china is made. The close relation between chronostratigraphy and sequence stratigraphy makes it possible for sequence stratigraphy to improve chronostratigraphic research. It is pointed out that multidisciplinary study in chronostratigraphy is necessary and should be promising and profitable.

关键词： sequence stratigraphy chronostratigraphy GSSP china.

Triassic Sequence Stratigraphy and Sea-Level Changes in Qomolongma Area, Southern Tibet, china: From Epicontinental Sea to Rift Basin

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Journal of earth Science 2000年第3期19卷 47-57页

作者： Shi Xiaoying Faculty of earth sciences and Land {2., china university of geosciences, beijing 100083. china

The Triassic in the Qomolongma area, southern Tibet, was deposited under an extensional tectonic setting from the Pangea supercontinent to continental rifting. From the Induan to Rhaetian, 12.depositional sequences (3rd order) have been recognized, which can be grouped into 5 sequence sets and in turn make up a well defined mesosequence (2.d order). Among the recognized marine transgressions, those at 2.0 Ma, 2.9 Ma, 2.1 Ma and 2.3 Ma respectively are particularly of significance and can be correlated widely across continents. The study shows that in Triassic the Qomolongma area experienced a sedimentary evolution from epicontinental sea to rift basin with the turning point at ca 2.8 Ma. During the early and middle epochs, the area was under epeiric sea, with carbonate ramp to mixed shoal environments predominant. In the late Carnian, the strong extension initiated listric faulting, thus resulting in rapid basement subsidence and the onset of a rift basin. From the late Norian to Rhaetian, it manifested as a rapid basin filling process in the area. Coupled with long term sea level fall, the excessive terrigenous influx led to the shift of environment from deep water prodelta to shore and finally to fluvial plain.

关键词： Triassic sequence stratigraphy sea level change cycles basin evolution southern Tibet.

A new Early Cretaceous lizard with well-preserved scale impressions from western Liaoning, china

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Progress in Natural Science:Materials International 2005年第2期15卷 67-73页

作者： JI Shu’an*(School of earth and Space sciences, Peking {2., beijing 100871, china) School of earth and Space sciences Peking University Beijing 100871 China

A new small lizard, Liaoningolacerta brevirostra gen. et sp. nov., from the Early Cretaceous Yixian Formation of western Liaoning is described in detail. The new specimen was preserved not only by the skeleton, but also by the exceptionally clear scale impressions. This lizard can be included within the taxon Scleroglossa based on its 2. or more presacrals, cruciform interclavicle with a large anterior process, moderately elongated pubis, and slightly notched distal end of tibia. The scales vary evidently in size and shape at different parts of body: small and rhomboid ventral scales, tiny and round limb scales, and large and longitudinally rectangular caudal scales that constitute the caudal whorls. This new finding provides us with more information on the lepidosis of the Mesozoic lizards.

关键词： new genus Squamata skeleton lepidosis Early Cretaceous western Liaoning

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., beijing 100871, china School of geosciences and resources, china {2. of geosciences,{12.) [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 {2. 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 {2. 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.