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Science Bulletin 2005年第15期 98-107页

作者： LI Yuecong1,2, XU Qinghai2, ZHAO Yingkui3, YANG Xiaolan4. XIAO Jule1, CHEN Hui2,5 & Lü Xinmiao5 1. Institute of geology and geophysics, Chinese Academy of Sciences, Beijing 100029, China 2. College of Resources and Environment, Hebei Normal University, Shijiazhuang 050016, China 3. department of Environmental Management, University of Central Lancashire, Preston, UN 4. Hebei Geography Institute, Hebei Academy of Sciences, Shijiazhuang 050011, China 5. Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China

In order to investigate the indication of major pollen types to source plants, 39 surface pollen samples are collected from 39 plant communities. The results show that diversity of pollen assemblages presents in different commu-nities. Chenopodiaceae pollen percentages are highest in Kalidium communities and Ceratoides communities (higher than 4.%, average is 63.4.), but high Ephedra pollen per-centages (higher than 3.3%, average is 16.5%)in Ceratoides communities make it distinguished from Kalidium communi-ties. Artemisia pollen percentages (more than 50%) are much higher than Chenopodiaceae (less than 35%) in Artemisia Communities. Nitraria pollen percentages (higher than 2%, average is 13.6%) are highest in Nitraria communities com-pared with those in other community patterns. Tamariceae pollen percentages (higher than 2%, average is 8.6%) are highest both in Tetraena and Reaumuria communities com-pared with those in other community patterns. But in Reau-muria communities, Artemisia pollen percentages are higher than Chenopodiaceae with some other pollen types such as Gramineae, Compositae, Leguminosae; on the contrary, in Tetraena communities, Artemisia pollen percentages are less than Chenopodiaceae with few other pollen types. Calli-gonum pollen only appears in Calligonum communities (higher than 2%,average is 5%). The results of cluster analysis (CLA) and detrended correspondence analysis (DCA) show that the pollen indication to source plants can be reflected by association indices (A), over-representation in-dices (O), under-representation indices (U), R-value, the av-erage pollen percentages where parent plants are absent (Xa) and the average pollen percentages where parent plants are present (Xp). Zygophyllum, Calligonum, Tetraena, Tribulus and Tamariceae can indicate source plants very well, owing to high A scores. Artemisia, Chenopodiaceae and Gramineae have high R-values, and Nitraria, Cruciferae and sedum have high O scores, so they are over-represente

关键词： eastern desert of China pollen indication association indices (A) over-representation indices (O) under-representation indices (U) correlation coefficients (CC) similarity coefficients (C) detrended correspondence analysis (DCA) cluster analysis (CLA) ratios of Nitraria and Ephedra (N/E) ratios of Ephedra and Artemisia (E/A) ratios of Artemisia and Chenopodiaceae (A/C).

Paleomagnetic Excursions Recorded in the Yanchi Playa in Middle Hexi Corridor, NW China Since the Last Interglacial

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Journal of Mountain Science 2004年第2期1卷 128-142页

作者： YANGTaibao YUYongtao LIJijun ANCongrong LIUJinfeng ZHANGJunyan KeyLaboratoryofWesternEnvironmentalChanges ChineseMinistryofEducationLanzhouUniversityLanzhou730000China departmentofGeography SchoolofGeosciencesNanjingNormalUniversityNanjing210097China Instituteofgeologyandgeophysics ChineseAcademyofSciencesBeo＇ing100029China

Paleomagnetic determinations on lithological profiles of two paralleled[( )-275(long )]drilling cores covering the past 130 kyr B.P., GT4. and GT60, from the Yanchi Playa in the arid Northwestern China, indicate that a series of pronounced paleomagnetic excursions have been documented. By correlating our results with published regional and worldwide reports, 4.excursion events out of 10 apparent reversal signals (labeled from GT-1 to GT-10) were identified as excursion events coeval with the Mono Lake Event ([(28.4.( )]kyr~[(25.8)( )]kyr), Laschamp Event ([(4..3)( )]kyr^4..5 kyr), Gaotai Event (82.8 kyr~[(72.4.25( )]kyr) and the Blake Event (127.4.kyr^113.3 kyr), respectively. GT-9 correlates with the above-mentioned Gaotai Event, GT-7 and GT-6 correspond to two stages of the Laschamp Event and GT-5 to the Mono Lake Event. It is noteworthy that the so-called Gaotai Event has not been reported as a pronounced paleomagnetic excursion in the Northwestern China. Every magnetic excursion event corresponds to paleointensity minima, anteceding those established abrupt paleoclimatic change events, such as the Younger Drays and the Heinrich Events (H1-H6)[(. )-250( )]Here,[( )-250( )]we tentatively[( )-250( )]propose that these geomagnetic excursions/reversals can be viewed as precursors to climate abruptness. During the transitional stages when the earths magnetic field shifted between a temporal normal and a negative period, the earths magnetic paleointensity fell correspondingly to a pair of minima. Although more precise chronology and more convincing rock magnetic parameter determinations are essentially required for further interpretation of their intricate coupling mechanism, these results may have revealed, to some extent, that the earths incessantly changing magnetic field exerts an strong influence on the onset of saw-tooth shaped abrupt climate oscillations through certain feedback chains in arid Central Asia or even North Hemispheric high latitude regions.

关键词： Paleomagnetism geomagnetic excursion the Late Pleistocene arid Northwestern China

Rainfall-induced landslide stability analysis in response to transient pore pressure——A case study of natural terrain landslide in Hong Kong

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Science China(Technological Sciences) 2003年第z1期46卷 52-68页

作者： LAN Hengxing, ZHOU Chenghu C. F. LeeWANG Sijing & WU Faquan State Key Laboratory of Natural Resources and Environmental System, Institute of Geographical Sci-ences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China department of Civil Engineering, Hong Kong University, Hong Kong, China 3. Institute of geology and geophysics, Chinese Academy of Sciences, Beijing 100029, China Chinese Acad Sci State Key Lab Nat Resources & Environm Syst Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China Univ Hong Kong Dept Civil Engn Hong Kong Hong Kong Peoples R China Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

Transient pore pressure in response to short intense rainfall process plays an important role in shallow landslide occurrence. Using GIS technology, we carry out the rainfall-induced landslide stability analysis in response to transient pore pressure by means of transient and unsaturated rainfall infiltration modeling. A case study is performed on the shallow landslide stability analysis in Hong Kong. Detailed analysis and discussion reached some useful conclusions on the tempo-spatial behavior and characteristics of slope stability response and pore pressure response to typical rainfall process. Comparison analysis is performed on some important issues including landslide stability response in different types of slopes with different hydraulic properties, antecedent rainfall and landslide stability, and the nature of pore pressure response time. These studies might give us an important insight into landslide tringgering mechanism and the hydrological process in response to rainfall, and provide systematic information and evidences for effective risk assessment and warning system establishment.

关键词： rainfall-induced landslide, transient pore pressure, landslide stability in response to rainfall, GIS.

Hydrothermal venting and basin evolution(Devonian,South China):Constraints from rare earth element geochemistry of chert

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Hydrothermal venting and basin evolution(Devonian,South Chin...

Magnetic Structure of Continental Crust: Implications for Crustal Structure and Evolution

中国科学院地质与地球物理研究所2006学术年会

作者： Daizhao Chen~a,Hairuo Qing~b,Xin Yan~a and He Li~a (a Institute of geology and geophysics,Chinese Academy of Sciences,PO Box 9825,Beijing 100029,China) (b department of geology,University of Regina,Regina,SK,Canada S4. 0A2)

This paper presents rare earth element(REE) geochemistry of siliceous deposits from which hydrothermal activity and basin evolution are elucidated,in the Late Devonian,in the Yangshuo basin,South China,where siliceous deposits widely occurred as nodular chert in the deep-water limestones and bedded chert interbeded with tuffaceous chert in the early Late *** nodular and bedded cherts are characterized by very low La abundances(avg. 2.07 and 2.4. ppm,respectively),intermediate negative Ce anomalies(Ce/Ce*:avg.0.69 and 0.61),slight to intermediate positive Eu anomalies(Eu/Eu*:avg.1.33 and 1.57),and low to intermediate shale-normalized La/Yb values(avg.0.86 and 0.52) and intermediate La/Ce values(avg.1.61 and 1.72).These suggest both nodular and bedded cherts formed in the open marine basin of South China,rather than in the intracontinental rift basin as previously assumed, with involvement both with seawaters as indicated by intermediate negative Ce anomalies and generally LREE-depleted patterns,and hydrothermal vent fluids as indicated by convex,less LREE-depleted patterns with apparent positive Eu *** comparison with nodular and bedded chert,the tuffaceous chert has the highest La abundances(avg.17.11 ppm),similar ranges of Ce anomalies(avg.0.63) and La/Ce values(avg.1.77),but lower La/Yb values(avg.0.4.) and no apparent positive Eu anomalies(avg.0.97).This suggests that the tuffaceous fallouts were also significantly modified by the hydrothermal fluid and *** spatial variations of Eu/Eu* values and degree of LREE-depletions in the studied basin are recognized,characterizing a spatially differential hydothermal activity that is not well discriminated by major element *** a difference in hydrothermal activity is interpreted as having been related to the intensity and depth of syndepositional tectonic activity,reconciling the structural pattern unraveled by stratigraphic packages.

关键词： REE patterns chert hydrothermal activity basin evolution open marine basin Late Devonian South China

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Journal of Earth Science 2000年第3期19卷 162-166页

作者： Liu Qingsheng The State Key Laboratory of Oil/Gas Reservoir geology and Exploitation of China, Chengdu 610059, China department of geophysics, China University of Geosciences, Wuhan 4.0074. China Gao Shan Faculty of Earth Sciences, China Universit

Magnetic structure of the continental crust is one of the important geophysical aspects of continental lithosphere. This paper reviews the achievements in the research into the magnetic structure and its significance for crustal tectonics, composition, metamorphic facies, crust mantle interaction and magnetization of deep crust. Further studies are suggested according to the basic principles of rock and mineral magnetism in terms of petrology, geochemistry and structural geology. Emphasis is placed on new geological ideas and synthetic studies of the relationship between deep geological processes and interpretation of gravity, magnetic, electrical and seismic data. The relationships between magnetic, density, electricity, velocity, geothermal structures and deep geodynamic processes are taken as a system for the research into the deep geology.

关键词： magnetic structure metamorphic facies crust mantle interaction.

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古长江河口湾充填潮流作用机制的初步探讨

海洋学报 1999年第3期21卷 73-82页

作者：朱玉荣同济大学海洋地质与地球物理系上海200092

长江三角洲的发育是以古长江河日湾的充填来实现的．研究潮汐、潮流在古长江河口湾充填中所起的作用，可深入了解长江三角洲的形成发育过程．建立了渤海、黄海、东海的二维潮流数学模型，数值模拟了冰后期最大海侵，即现今长江三角洲地... 详细信息

长江三角洲的发育是以古长江河日湾的充填来实现的．研究潮汐、潮流在古长江河口湾充填中所起的作用，可深入了解长江三角洲的形成发育过程．建立了渤海、黄海、东海的二维潮流数学模型，数值模拟了冰后期最大海侵，即现今长江三角洲地区为巨大河口湾时的M2潮汐、潮流．在此基础上，计算了古长江河口湾及其周围海域8种粒径泥沙的潮平均悬移与推移输沙率，并根据输沙率散度的正负，划分了海底冲刷区与淤积区．根据计算结果得出，冰后期最大海侵时，存在大致以古长江河口湾湾口中点为腹点、波腹线向海凸起的独特驻潮波波腹区．在其控制下，外海潮流大致以古长江河口湾湾口中点为顶点作辐聚、辐散运动．在古潮流场作用下，经历每一个潮周期后，古长江河口湾周围海域的泥沙均向河口湾内净输运，并在河口湾内淤积．古长江河口湾的充填是在长江带来大量泥沙，外海的潮汐、潮流又有利于泥沙向河口湾内净输运，且在河口湾内沉积的情况下实现的．外海的潮汐、潮流为古长江河口湾的充填、长江三角洲的发育提供了必要而又有利的水动力环境．

关键词：海侵古长江河口湾潮流泥沙输运数值模拟

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高邮凹陷戴南—三垛组古生物与沉积环境演变

同济大学学报（自然科学版） 1999年第3期27卷 366-370页

作者：董荣鑫同济大学海洋地质与地球物理系上海200092

依据苏北高邮凹陷戴南—三垛组岩芯中所见古生物化石，通过古生物生态组合的分析。

关键词：沉积环境古生物高邮凹陷戴南组三垛组苏北

Evaluation of Slip Rate on Astara Fault System, North Iran

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Journal of Earth Science 2016年第6期27卷 971-980页

作者： Amir Barzegari Rasoul Esmaeili Mohammad Ebrahimi Ali Faghih Manucher Ghorashi Hamid Nazari Depatment of geology Faculty of SciencesIslamic Azad University North Tehran BranchTehran ***Iran State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China department of geology Faculty of SciencesUniversity of ZanjanZanjan ***Iran department of Earth Sciences College of SciencesShiraz UniversityShiraz 71454Iran Geological Survey of Iran Tehran 131851494Iran Research Institute for Earth Sciences Geological Survey of lranTehran 131851494Iran

Due to its strategic location, the Astara fault system （AFS）, which is located in Iran, has given rise to a number of earthquakes. In spite of its frequent seismic events, limited information is available for AFS. Slip rate is one of the important variables for future scrutiny of seismic risk of this fault system. The main objective of this research is to study slip rates at intermediate and short terms for this fault system using geological, geodetic observations and empirical method. Using the geological data, the intermediate-term horizontal and vertical slip rates for AFS have been determined to be 2.8±0.2 and 0.27±0.03 mm/year, respectively. In addition, the short-term slip rates of the fault, based on the geodetic method （using displacement values of two GPS stations： HASH and DAMO） and assuming attenuation of 60% （to fold the sediment of South Caspian Basin and shortening of Talesh Mountain range）, determined to be 1.23±0.03 and 2.05±0.05 mm/year for the horizontal and vertical slips, respectively. Finally, evaluation of the slip rate using empirical relationship yields 10 mm/year for the entire fault system, which seems rather implausible.

关键词： Astara fault system intermediate slip rate geodetic slip rate empirical slip rate Gutenberg-Richter method focal depth.

Mineralogical and geochemical evidence for coupled bacterial uranium mineralization and hydrocarbon oxidation in the Shashagetai deposit,NW China

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Mineralogical and geochemical evidence for coupled bacterial...