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The *** climate abrupt events in the early and middle Holocene:Stalagmite oxygen isotope record from Maolan,Guizhou,China

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Science China Earth Sciences 2005年第4期48卷 530-537页

作者： QIN Jiaming1, YUAN Daoxian1, CHENG Hai2, LIN Yushi1, ZHANG Meiliang1, WANG Fuxing1, R. L. Edwards2, WANG Hua1 & RAN Jingcheng3 1. The Karst Dynamic Laboratory, IKG, CAGS, Guilin 54.004. China 2. geology and geophysics department, minnesota {4., mn5.45., usa 3. The Management of Maolan National Nature Reserve, Libo 5584.0, China 1. The Karst Dynamic Laboratory 541004 IKG CAGS Guilin China 2. geology and geophysics department Minnesota University 55455 MN USA 3. The Management of Maolan National Nature Reserve 558400 Libo China

The isotope records which range from 3.9 kaBP to 15.7 kaBP with an average resolution of 90 a have been obtained from 4. cm to 193.6 cm of the upper part of D4.stalagmite from Dongguo Cave in Libo, Guizhou, by using system TIMS U-series dating and carbon and oxygen stable isotope *** study indicates that the last cold event, the YD (Younger Dryas) event, of the last glacial period was apparently shown in D4.record, which started from 12.80 kaBP and ended in 11.58 kaBP, with a great range of drop in temperature. The end of the last glacial period was consistent with the termination I in oceanic isotope records and was with time limit of 11.3 kaBP. The three most distinct cold events in the early and middle Holocene occurred respectively in 10.91 kaBP, 8.27 kaBP and 4.75 kaBP, with a range of drop in tem- perature reaching 2—5℃. The climate abrupt events in thousand and hundred years scale re- corded in stalagmite δ O can be compared to those in GISP2 ice cores from Greenland in their 18 happening time and the range of their lasting time. The cold events in 8.27 kaBP and 4.75 kaBP can also be compared to CC3 stalagmite records in Ireland, which indicate that climate changes of short range in China monsoon areas, western Europe and polar regions, have the same driv- ing factor. This has a global significance. In addition, the trend of record curves in some time- stages is apparently different, which reflects probably the difference between environment in monsoon climate areas and in polar regions.

关键词： isotope record, climate event, stalagmite, Libo, Guizhou.

Paleobiogeography of Ostracoda and Foraminifera in the China sea area

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Acta Oceanologica Sinica 1991年第1期10卷 93-105页

作者： Wang Pinxian and Zhao Quanhong department of Marine geology, Tongji university, Shanghai, 200092, China Dept Marine geology Tongji Univ Shanghai 200092 China China

The distribution of ostracods and benthonic foraminifers in the China sea area is briefly reviewed from the paleobio-geographic viewpoint in this paper. Three regions can be distinguished in the area on the basis of modern distribution data: Region I (the Huanghai Sea and the Bohai Sea) with cool and temperate forms, Region I (the East China Sea and the northern part of the South China Sea) with subtropical warm-water forms and Region Ⅲ (central and southern parts of the South China Sea) with larger foraminifers and other tropical warm-water forms. The occurrence of Nummulites-Discocyclira fauna in the Eocene deposits of the East China Sea indicates a northward extension of tropical zoogeographical region at the time, whereas the distribution pattern of the Miocene Nephrolepidina-Miogypsiua-Austrotrillina fauna in the South China Sea resembles that of the present larger-foraminiferal fauna. In the South China Sea and Taiwan, a warm-water fauna with Asterorotalia and Pseudorotalia first appeared in late Miocene and then flourished in the Pliocene. Its northward invasion into the Bohai Sea area during late Pleistocene may be related to changes in current system. Many of the endemic foraminiferal and ostracod genera and species ( Sinocytheridea etc. ) in recent coastal faunas probably have originated from the South China Sea, and their occurrence in Japan or Australia may be indicative of ties between these areas during glacial times.

关键词： Paleobiogeography of Ostracoda and Foraminifera in the China sea area

THEORY ON AUTOGENOUS GRIND BLADE AND INK-MAKING OF CHINA'S SHE INKSLAB

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Chinese Science Bulletin 1989年第6期34卷 495-498页

作者：郑辙 department of geology Peking University

She inkslab, originated from She County, is carved out of slates or phylliteslates occurring in the Longwei Mountain of Wuyuan County, which was in history directly under the administration of She County, Jiangxi Province, and became the treasure in the study to the emperor in the late Tang Dynasty because of such finequalities as being black sparkling and compact in appearance, making ink like oil, storing ink in the inkslab for a long time without drying, and skillful carving.

关键词： She inkslab autogenous grind blade ink-making two-dimensional bladeinkslab edge.

EXPERIMENTAL STUDY OF FRICTION FACTOR FOR GROUNDWATER FLOW IN A SINGLE ROUGH FRACTURE

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Journal of Hydrodynamics 2009年第6期21卷 820-825页

作者： CHEN Zhou QIAN Jia-zhong LUO Shao-he ZHAN Hong-bin School of Resources and Environmental Engineering Hefei University of Technology Hefei 230009 China department of Resources and Environment Henan Polytechnic University Jiaozuo 454010 China department of geology and geophysics Texas A and M University College Station TX 77843-3115 USA

To study the relationships between the friction factor f and the flow type in a single rough fracture, the formulae of f for both unconfined and confined flows are deduced based on previous studies. The relationships between f and the Reynolds number （Re） for different relative roughnesses are investigated experimentally. The Moody-type diagram, based on the deduced formula of f, is also plotted and the hydraulic characteristics of the flow in a rough fracture are analyzed. Results show that the Moody-type diagram of the experiment has a similar distribution to that of the conventional Moody diagram. It is found that the value of f in the experiment is much smaller than that of the conventional Moody diagram and turbulent flow appears easier for rough fractures, which can be explained by the separation phenomenon in boundary layers. The critical Re ranging from 650 to 700 in rough fractures is concluded based on the experimental results. It also can be concluded that the friction factor f is related not only with the Re and the relative roughness but also with the absolute roughness.

关键词： friction factor rough fracture Moody diagram critical Reynolds number ( Re ) boundary layer

The Relationship between Microtexture Types and Indices of Physico-Mechanical Properties of Loess in China

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Acta Geologica Sinica(English Edition) 1989年第4期63卷 433-443,453页

作者： Lei Xiangyi department of geology, Northwest university, Xi’an, Shaanxi

The paper deals mainly with the relationship between the microtexture types and the indices of physicomechanical properties of loess. The results of study demonstrate that the study of microtextures of loess is of imp... 详细信息

关键词： Pro The Relationship between Microtexture Types and Indices of Physico-Mechanical Properties of Loess in China

A FINITE AMPLITUDE ANALYSIS OF TUNNEL DEFORMATION BY THE FINITE ELEMENT METHOD WITH HIGHLY VISCOUS FLUID

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Acta Mechanica Sinica 1985年第1期1卷 27-36页

作者： Wang Ren Liang Beiyuan Sun Xunying (department of geology,Peking university) 1. department of geology Peking University Beijing China

A finite element method for highly viscous fluid is used to calculate the velocity andstress fields in the surrounding soft rock of a tunnel. In order to fit the calculated values with themeasured displacement of tunn... 详细信息

关键词： finite element method tunnel highly viscous fluid

Biodegradation and origin of oil sands in the Western Canada Sedimentary Basin

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Petroleum Science 2008年第2期5卷 87-94页

作者： Zhou Shuqing Huang Haiping Liu Yuming School of Energy Resource China University of Geosciences Beijing 100083 China department of geology and geophysics University of Calgary T2N 1N4 Calgary Canada

The oil sands deposits in the Western Canada Sedimentary Basin （WCSB） comprise of at least 85% of the total immobile bitumen in place in the world and are so concentrated as to be virtually the only such deposits that are economically recoverable for conversion to oil. The major deposits are in three geographic and geologic regions of Alberta： Athabasca, Cold Lake and Peace River. The bitumen reserves have oil gravities ranging from 8 to 12° API, and are hosted in the reservoirs of varying age, ranging from Devonian （Grosmont Formation） to Early Cretaceous （Mannville Group）. They were derived from light oils in the southern Alberta and migrated to the north and east for over 100 km during the Laramide Orogeny, which was responsible for the uplift of the Rocky Mountains. Biodegradation is the only process that transforms light oil into bitumen in such a dramatic way that overshadowed other alterations with minor contributions. The levels of biodegradation in the basin increasing from west （non-biodegraded） to east （extremely biodegraded） can be attributed to decreasing reservoir temperature, which played the primary role in controlling the biodegradation regime. Once the reservoir was heated to approximately 80℃, it was pasteurized and no biodegradation would further occur. However, reservoir temperature could not alone predict the variations of the oil composition and physical properties. Compositional gradients and a wide range ofbiodegradation degree at single reservoir column indicate that the water-leg size or the volume ratio of oil to water is one of the critical local controls for the vertical variations ofbiodegradation degree and oil physical properties. Late charging and mixing of the fresh and degraded oils ultimately dictate the final distribution of compositions and physical properties found in the heavy oil and oil sand fields. Oil geochemistry can reveal precisely the processes and levels that control these variations in a given field, which opens the

关键词： Western Canada Sedimentary Basin (WCSB) oil sands biodegradation mixing

Electrical Properties of Expanded Graphite Intercalation Compounds

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Journal of Materials Science & Technology 2001年第3期17卷 371-374页

作者： Xiuyun CHUAN department of geology, Peking university, Beijing 100871, China Daizhang CHEN and Xunruo ZHOU department of Materials Science, China university of Geosciences, Beijing 100083, China E-mail: cxyljhcj@*** Peking Univ Dept Geol Beijing 100871 Peoples R China China Univ Geosci Dept Mat Sci Beijing 100083 Peoples R China

The intercalation compounds of CuCl2 were synthesized with expanded graphite, whose magnitude of the electrical conductivity is about 10(3)S(.)cm(-1). Their electrical conductivity is 3 similar to6 times as high as that of the expanded graphite, and about 10 times as high as that of GIC made of the non-expanded graphite. The microanalysis results of chemical compounds by X-ray energy spectrum scanning of TEM testified that the atomic ratio of chloride and cupric is nonstoichoimetric. The multivalence and exchange of electrovalence of the cupric ion was confirmed by the XPS-ESCA. Vacancy of chlorine anion increases the concentration of charge carrier. The special stage structure, made of graphite and chloride, produces a weak chemical bond belt and provides a carrier space in the direction of GIC layer. These factors develop the electrical properties.

关键词： In Ph Electrical Properties of Expanded Graphite Intercalation Compounds Graphite ESCA

Discovery and analysis of ultra-micro grinding grain texture in slipping lamellae of ductile-brittle zone

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Science China Earth Sciences 2004年第3期47卷 265-271页

作者： GE Heping1, SUN Yan1, LU Xiancai1, ZHU Wenbin1, GUO Jichun1, LIU Deliang2 & Chi-yuen Wang3 1. department of Earth Sciences, Nanjing university, State Key Laboratory of Mineral Deposit, Nanjing 210093, China 2. department of Earth and Space Sciences, university of Science and Technology of China, Hefei 230026, China 3. department of geology and geophysics, university of California, Berkeley, CA 94.20, usa Nanjing Univ Dept Earth Sci State Key Lab Mineral Deposit Nanjing 210093 Peoples R China Univ Sci & Technol China Dept Earth & Space Sci Hefei 230026 Peoples R China Univ Calif Berkeley Dept Geol & Geophys Berkeley CA 94720 USA

Based on the observation of the deep bore cores sampled from the State of Cali-fornia, usa, preferred arranged particulate concentration belts were found in the ultra-slipping lamellae. And the same phenomenon was found again later in the bore cores from the petroleum basin in the Northern Shaanxi Province. It may be the product of the dynamic processes involv-ing tumbling, grinding and compresso-shearing functions, so the spherical particulates with ul-tra-size of nm and mm are called grinding grain. The formation of the grinding grains is related with the ductile-brittle deformation, the lateral pressure of the slipping, and the very low grade of dynamic metamorphism of the rocks. Based on the systematic analysis, it is indicated that some elements like Nb and Ta are enriched in the grinding grains in the granitic rocks because of the chemical differentiation, and that the slipping lamellae bearing grinding grains in mudstone with smear efficiency prove a perfect seal for oil and gas reservoirs. Meanwhile, the paper provides bases for the studies on the fast stick-slip movement and shear paradigm.

关键词： slipping lamellae, grinding grain texture, ductile-brittle deformation, smear efficiency.