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Science China earth sciences 2004年第10期47卷 896-911页

作者： ZHANG Changhou1,2. WU Ganguo1,2. WANG Genhou2. ZHANG Weijie2.& SONG Honglin2.1. Key Laboratory of Lithospheric Tectonics and Lithoprobing Technology, China university of geosciences, Ministry of Education of China, {2. 100083. China 2. school of earth sciences and Mineral resources, China university of geosciences, {2. 100083. China Key Laboratory of Lithospheric Tectonics and Lithoprobing Technology China University of Geosciences Ministry of Education of China Beijing China school of earth {2. and Mineral resources China University of Geosciences Beijing China

The northwest trending tectonic belt in the middle part of the Mesozoic intraplate Yanshan Orogenic Belt, northeast Hebei Province, is composed of thrusts, extensional faults, strike-slip faults and syntectonic sedimentations as well. The northeastward basement-involved major thrusting deformation occurred between 174Ma and 168MaBP and was followed by an intrusion of the granitic plutonic rocks. As a part of the post-thrusting extensional deformations a northwest extending volcano-sedimentation system of Late Jurassic and Early Cretaceous formed in the southwest side of the belt. These volcano-sedimentary sequences are divided into Tuchengzi Formation, Zhangjiakou Formation, Yixian Formation and Jiufotang Formation re- spectively. They are characterized by southeastward migration as a result of the increasing down-dip slip displacement along the major extensional fault toward the southeast of the belt. The provenance area of the Jiufotang Formation north to it experienced southwestward thrusting during and after its later sedimentation. The thrusting in this stage resulted in the formation of an asymmetric footwall syncline with vergence to SW in the Jiufotang Formation in the NE side of the basin. Finally a dextral strike-slip deformation occurred along the NW tectonic belt. The striking tectono-geomorphological features and present seismic activities along this belt indicate that it has been being active since Cenozoic era and is still in the active state at present. This northwest extending tectonic belt was following the same direction and location as the existing fault systems within the basement as revealed by former geological and geophysical studies. So it is reasonable to infer the Mesozoic deformation along this belt to be a result of reactivation of the basement structures in a favorable tectonic stress field. The reactivation of basement struc- tures might be taken as one of the mechanisms of intraplate deformation and orogeny.

关键词： Yanshan Orogenic Belt, northwest extending tectonic complex, thrust system, geochronology.

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Pioneer organisms after F-F mass extinction in Dushan region,Guizhou Province,and their significance in establishing new ecosystem

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Science China earth sciences 2006年第5期49卷 449-460页

作者： WANG Yue1, 2. WANG Xunlian1 & SHI Xiaoying1 1. school of earth {2. and resources, China university of geosciences, beijing 100083. China 2. school of resources and Environment, Guizhou university, Guiyang 550003, China school of earth {2. and resources China University of Geosciences Beijing China school of resources and Environment Guizhou University Guiyang China

After mass extinctions, most areas became “ecologically barren areas” lacking or even without ecosystem over an extensive region. Studying the pioneer organisms and the reconstruction process of a new ecosystem in the “ecologically barren area” is very important for revealing the evo- lution after bio-mass extinctions. In the Dushan region, Guizhou Province, China, the trace fossils appeared and flourished evidently earlier than body fossils after Frasnian-Famennian (F-F) mass extinction. The pioneer organisms and pathfinders in the “ecologically barren areas” are the trace-makers that are deposit-feeders with relatively simple structure and conformation on or near the deposit surface. The trace-makers have undergone an evolutionary process that their trace structures changed from simple to complex, and their living and moving areas and spaces enlarged from linear to planar and then to three-dimension spaces. Those characters show that the ability of the trace-makers to deposits and their efficiency of looking for food have been enhanced gradually and that those trace-makers constructed gradually a base for the new ecosystem. This process is similar to that of the trace fossils near the Precambrian-Cambrian boundary. In the Dushan area, only the recovery intervals have been identified for the Famennian body fossils, with no eminent radiation interval recognizable due to the Devonian-Carboniferous (C-D) mass ex- tinction. However, both the recovery and radiation intervals may be clearly recognized in the Famen- nian trace fossils based on their conformation and diversity. The evolution and diversification of the trace fossils in the “ecologically barren area” is considered to have played a role of necessary foun- dation for the recovery of body fossils in the ecological chain. With the gradual disappearance of the unfavourable environment factors resulting in the F-F mass extinction, a new ecosystem was reconstructed in the “ecologically barren area” through a three-

关键词： pioneer organisms, reconstruction of ecosystem, trace fossils, F-F mass extinction, Later Devonian, Dushan region, Guizhou Province, China.

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Indian Ocean-MORB-type isotopic signature of Yushigou ophiolite in North Qilian Mountains and its implications

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Science China earth sciences 2006年第6期49卷 561-572页

作者： HOU Qingye1,2. ZHAO Zhidan1,2. ZHANG Hongfei3, ZHANG Benren3 & CHEN Yuelong2.1. State Key Laboratory of Geological Processes and Mineral resources, China university of {2., beijing 100083. China 2. school of earth Science and Mineral resources, China university of {2., beijing 100083. China 3. Faculty of earth sciences, China university of {2., Wuhan 430074, China State Key Laboratory of Geological Processes and Mineral resources China University of Geosciences Beijing China school of earth Science and Mineral {2. China University of Geosciences Beijing China Faculty of earth sciences China University of Geosciences Wuhan China

In order to explore the disputed issue concerning the tectonic affinity ofthe ancient ocean mantle of North Qilian Mountains (NQM), geochemical and Sr, Nd, Pb isotopiccompositions of pillow basalts of the Yushigou Ophiolite (YSGO) suite from NQM have been analyzedsystematically. The pillow basalts exhibit tholeiitic characteristics, with flatchondrite-normalized REE patterns ((La/Yb)_N = 0.98—1.2.). They display no Nb, Ta, Zr, Hf negativeanomalies, and show MORB features in 2.b-Zr/4-Y and Ti/100-Zr-YX3 tectonic discrimination *** results indicate that the Yushigou ophiolite is most likely to be formed in a mid-ocean ridgeor mature back-arc basin. Their isotopic data show a relatively broad and enriched ^(87)Sr/^(86)Sr(0.70509 — 0.70700), restricted ^(143)Nd/^(144)Nd (0.512.55-0.512.78). Pb isotopes are in the rangeof ^(2.6)Pb/^(2.4)Pb (18.054-2..562., ^(2.7)Pb/^(2.4)Pb (15.537-15.743) and ^(2.8)Pb/^(2.4)Pb(38.068-38.530). These isotopic data imply that the basalts originated from the depleted mantle(DMM), with the involvement of enriched mantle components (mainly EMII). Geochemical comparisonsbetween the basalts in YSGO and the MORB-type basalts of ophiolite suites occurring in the knownancient Tethyan tectonic domain indicate that the ancient oceanic mantle represented by YSGO suiteforming in early Paleozoic in the North Qilian Moutains is very similar to the Tethyan mantle inboth trace elements and isotopic compositions. The North Qilian Mountains should be a part of theTethyan tectonic domain in early Paleozoic. This further implies that the Tethyan tectonic domaincan be deduced to early Paleozoic in the study area, which will be helpful to discussing thetectonic affinity and evolution of the North Qilian Mountains.

关键词： geochemistry, Indian Ocean-MORB-type isotopic signatures, Tethyan tectonic domain, Yushigou ophiolite, North Qilian Mountains.

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The role of aerial algae in the formation of the landscape of the Yunnan Stone Forest,Yunnan Province, China

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Science China earth sciences 2004年第9期47卷 846-864页

作者： TIAN Youping1,3, ZHANG Jie2. SONG Linhua1 & BAO Haosheng2.1. Institute of Geographic sciences and Natural resources Research, Chinese Academy of sciences, beijing 100101, China 2. Department of Geography, Nanjing university, Nanjing 2.0093, China 3. school of earth sciences and resources, China university of geosciences, beijing {12. China Institute of Geographic sciences and Natural resources Research Chinese Academy of Sciences Beijing China school of earth {2. and resources China University of Geosciences Beijing China Department of Geography Nanjing University Nanjing China

Aerial algae on the surface of carbonate rocks at the Stone Forest, Shilin County, Yunnan Province, China, and their bioerosion were investigated in the field and studied in the laboratory in detail. Through the observation, identification and statistics of more than one hun- dred algal samples and rock samples with the optical microscopes (stereomicroscope, biological microscope) and the scanning electronic microscope (SEM), the relationships between erosional forms on the surface of the Stone Forest and algae and/or algal communities and the genetic mechanism for the formation of erosional forms were analyzed. It is suggested that aerial algae play an active role in bioerosive processes that may affect the formation of karst erosional forms. These effects include both direct and indirect ones. The direct effect is the initiative control (algal shape-controlling role) of algae on the formation of karst forms of various scales, mostly mi- cro-scale (<10-3m) and minor-scale (10-3-10-1m) erosional forms. The algal shape-controlling roles can be divided into the algal individual shape-controlling role and the algal community shape-controlling role. The former mostly controls the formation of micro-scale erosional forms, while the latter mostly controls the formation of micro-scale and smaller minor-scale erosional forms. The indirect effect refers to the promoting role of algae in the formation of karst forms, which may affect the formation of karst forms of all types and scales. The bioerosion of algae accelerates the weathering process of the whole Stone Forest karst landforms.

关键词： aerial algae, bioerosion, the Stone Forest, Yunnan Province, China.

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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 {2. sciences and resources, China university of Geo- sciences, beijing 100083. China Department of Geology and Key Laboratory for Continental Dynamics Northwest University Xi’an China school of earth {2. and resources China University of Geosciences Beijing 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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Paleoceanographic evolution recorded in the northern South China Sea since 4 Ma

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Science China earth sciences 2005年第12期48卷 2166-2173页

作者： HUANG Baoqi1,2. JIAN Zhimin2.& WANG Pinxian2.1. school of earth and Space {2., Peking university, beijing 100871, China 2. Laboratory of Marine Geology, Tongji university, Shanghai 2.0092. China school of earth and Space {2. Peking University Beijing China Laboratory of Marine Geology Tongji University Shanghai China

Upper water structure over the last 4 million years in the northern South China Sea (SCS) was reconstructed by sea surface temperature (SST) and primary productivity estimated by changes in the abundance of planktonic foraminifer, planktonic foraminifer transfer function, and the accumulation rate of benthic foraminifera. Results of SST and primary productivity show that SST gradually decreased since 4 Ma, but differential seasonal temperature and primary productivity increased in steps mainly at about 3.1, 2.7, 2.1, 1.6, 0.9 and 0.5 Ma. Comparison with tectonics and orbital variations indicates that phased rising of the Tibet since 3.6 Ma, closing of Panama and Indonesian seaways, and orbital changes were responsible for the changes of upper water structure in the SCS, respectively.

关键词： northern South China Sea, upper water structure, Late Pliocene, planktonic foraminifer, ODP 1146.

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Calculating soil moisture by remote sensing and analyzing hydrologic cycle process in the Yellow River basin

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Science China(Technological sciences) 2004年第Z1期47卷 1-13页

作者： YANG Shengtian1 & LIU Changming1, 2.1. school of Environmental sciences, {2. Normal university, {2. 100875, China 2. Institute of Geographic Science and Natural resources Research, {2. 100101, China school of Environmental sciences Beijing Normal University Beijing China Institute of Geographic Science and Natural resources Research Beijing China

Based on the AVHRR pathfinder remote sensing data, soil moisture, precipitation and evaporation during the period of 1982.1998, soil moisture of all layers of soil-profile (0—1 m) in the Yellow River basin over the 17 years are calculated by the remote sensing model of calculating soil water. The Yellow River basin is divided into seven subcatchments as control sections at the location of six hydrologic stations (Lanzhou, Toudaoguai, Longmen, Sanmenxia, Huayuankou and Lijin). After calculating soil moisture and obtaining runoff data and precipitation data, the dynamical features of hydrological cycle in the Yellow River basin are analyzed for the period from 1982.to 1988 using water balance method. The conclusions are as follows: It is feasible to calculate the soil water on the macro-scale, in the soil profile with temporal continuity by means of remote sensing and survey in land. Some values of the key water cycle factors in the Yellow River are obtained, which include the annual precipitation of 4000 km3, the evapotranspiration of 3000-3500 km3, and the soil moisture transformation of ?500- 500 km3. Consequently, we analyzed the process of the water cycle in the Yellow River over the 17 years, and the results show that the segment upstream of Lanzhou city is a relatively humid region, and the area of internal waters and the reaches of Shanshan is the most desiccated region. Therefore, the runoff in the depth process is intensive and the runoff-generating process is weak in more arid regions.

关键词： the Yellow River, soil moisture, remote sensing, hydrologic cycle.

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Fractal Characteristics of Coal Pores Based on Classic Geometry and Thermodynamics Models

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Acta Geologica Sinica(English Edition) 2011年第5期85卷 1150-1162页

作者： CAI Yidong~1,LIU Dameng~(1,*),YAO Yanbin~1,LI Junqian~1 and LIU Junlai~2.1 school of Energy resources,China {2. of geosciences,beijing 100083.China 2.school of earth Science and resources,China {2. of geosciences,beijing 100083.China school of Energy resources China University of Geosciences Beijing 100083 China school of earth Science and {2. China University of Geosciences Beijing 100083 China

To better understand the characteristics of coal pores and their influence on coal reservoirs, coal pores in eight main coalfields of North China were analyzed by mercury porosimetry and scanning electron microscopy（SEM）.Fractal characteristics of coal pores（size distribution and structure） were researched using two fractal models:classic geometry and *** two models establish the relationship between fractal dimensions and coal pores *** results include:（1） SEM imaging and fractal analysis show that coal reservoirs generally have very high heterogeneity;（2. coal pore structures have fractal characteristics and fractal dimensions characteristic of pore structures are controlled by the composition（e.g.,ash,moisture,volatile component） and pore parameters（e.g.,pore diameter,micro pores content） of coals;（3） the fractal dimensions（D;and D;） of coal pores have good correlations with the heterogeneity of coal pore *** fractal dimensions correlate to higher heterogeneity of pore *** fractal dimensions（D;and D;） have strong negative linear correlations with the sorted coefficient of coals （R;=0.719 and 0.639,respectively） that shows the heterogeneity of coal pores;（4） fractal dimension D;and petrologic permeability of coals have a strong negative exponential correlation（R;=0.82..However, fractal dimension D;and petrologic permeability of coals have no obvious correlation;and（5） the model of classic geometry is more accurate for fractal characterization of coal pores in coal reservoirs than that of thermodynamics by optimization.

关键词： coal pores mercury porosimetry fractal dimensions thermodynamics model classic geometry model

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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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Comparative study on CO_2.corrosion behavior of N80,P110,X52.and 13Cr pipe lines in simulated stratum water

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Science China(Technological sciences) 2010年第9期53卷 2342-2349页

作者： CAI YiDong1,GUO PengChao1,LIU DaMeng1,CHEN ShiYu2.& LIU JunLai3 1 school of Energy resources,China {2. of geosciences,beijing 100083.China 2.school of Materials Science and Engineering,{2. of Science and Technology beijing,beijing 100083.China 3 school of {12. sciences and resources,China {2. of geosciences,beijing 100083.China school of Energy resources China University of Geosciences Beijing China school of Materials Science and Engineering University of Science and Technology Beijing Beijing China school of earth {2. and resources China University of Geosciences Beijing China

To better understand the carbon dioxide (CO2. corrosion behavior of carbon steel and its influence on petroleum development (including drilling,production and transportation) in the Daqing Oilfield,CO2.corrosion behaviors of N80,P110,X52.and 13Cr pipe lines in simulated solution at high temperature and high pressure condition are investigated by dynamic corrosion experiments,scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS) *** show that the corrosion rate of all pipe lines increases quickly when CO2.partial pressure increases from 0.5 to 1.5 MPa,but it slows down when CO2.partial pressure further increases from 1.5 to 4.5 MPa,during which localized corrosion is *** the experimental temperature ranges from 60 to 12.°C,localized corrosion *** corrosion rate of all pipe lines decreases sharply when the temperature changes from 60 to 100°C,and it becomes stable after the temperature is higher than 100°*** the flow rate is in the range of 0–1.5 m/s,the corrosion rate of sample X52.remains unchanged,but localized corrosion gradually becomes very serious when the flow rate further *** analyzing the corrosion product scales of sample 13Cr,some remarkable phenomena are *** the temperature range of 60–100°C,the corrosion product scales are loose and thick,but become very compact when the temperature increases above 100°*** the later case,localized corrosion is *** main components of the corrosion product scales are FeCO3 and Cr2.3.

关键词： CO2 corrosion pipe lines weight loss SEM EDS

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