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Origin of the Red earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science china earth sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2, JI Junfeg3, WANG Xiaoyong1,7, ZHAO Jingbo4, HUANG Baochun5 & LI Zhen6 1. SKLLQG, Institute of earth Environment, Chinese Academy of sciences, Xi’an 710075, china 2. department of Urban and Resources sciences, nanjing university, nanjing 210093, china 3. department of earth sciences, nanjing university, nanjing 210093, china 4. department of Geography, Shaanxi Normal university, Xi’an 710062, china 5. Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 100029, china 6 department of Geography, Qinghai Normal university, Xining 810008, china 7. Graduate School of the Chinese Academy of sciences, Beijing 100039, china 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate School of the Chinese Academy of sciences Beijing 100039 China 2. department of Urban and Resources sciences Nanjing University Nanjing 210093 China 3. department of earth sciences Nanjing University Nanjing 210093 China 4. department of Geography Shaanxi Normal University Xi’an 710062 China 5. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. department of Geography Qinghai Normal University Xining 810008 China

The Red earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red earth sequenceconsists of 25 visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the ChineseLoess Plateau. Grain-size analysis shows that the Red earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red earth *** REE distributions of the loess-soil and the Red earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the Redearth deposition predates 11.4 Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

Eclogites in the interior of the Tibetan Plateau and their geodynamic implications

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Chinese Science Bulletin 2009年第15期54卷 2556-2567页

作者： ZHANG KaiJun1,2 & TANG XianChun2,3 1 department of earth sciences, nanjing university, nanjing 210093, china 2 Guangzhou Institute of Geochemistry, Chinese Academy of sciences, Guangzhou 510640, china 3 Graduate university of Chinese Academy of sciences, Beijing 100049, china department of earth sciences Nanjing University Nanjing 210093 China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Graduate university of Chinese Academy of sciences Beijing 100049 China

Eclogites have been recently reported in the interior of the Tibetan Plateau, including in the central Qiangtang metamorphic belt, in the Basu metamorphic massif of the eastern Bangong-Nujiang suture zone, and at Songdo and Pengco in the eastern Lhasa terrane. Some typical ultrahigh-pressure (UHP) metamorphic phenomena, e.g., garnet exsolution from clinopyroxene, were documented in the Basu and Pengco eclogites. The UHP metamorphism in the interior of the Tibetan Plateau marked by these eclogites generally took place in the Early Mesozoic. Along with exhumation of these eclogites, (post-) collision-related magmatism extensively occurred around the central Qiangtang belt, the eastern Ban-gong-Nujiang suture zone, and the eastern Lhasa terrane. The occurrence of these Early Mesozoic ec-logites manifests an out-of-sequence evolution of the Tethys, and they could be a product of diachro-nous collision between the eastern Qiangtang terrane and the irregular continental margin of the united western Qiangtang-Lhasa plate, along the linked eastern Bangong-Nujiang-central Qiangtang zone. The collision-related magmatic rocks could have been originated from lithospheric thickening, melting, or detachment due to the collision. The presence of UHP metamorphic rocks in central Qiangtang and Basu implies likely continental deep-subduction, and the denudation of these two metamorphic zones could have served as the source of the Triassic turbidites in the Songpan-Garzê complex and the Ju-rassic turbidites in the western Bangong-Nujiang zone, respectively. However, studies of the eclogites in the interior of the Tibetan Plateau just began, and many principal aspects still remain to be explored, such as their distributions, typical lithologies and minerals, temperature-pressure conditions, timing of formation and exhumation, protoliths and tectonic setting, and relationship with the evolution of the Tethys and large-scale basins in Tibet.

关键词：地球动力学意义青藏高原榴辉岩

Zircon SHRIMP U-Pb geochronology and petrogenesis of the plagiogranites from the Lagkor Lake ophiolite,Gerze,Tibet,china

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Chinese Science Bulletin 2007年第5期52卷 651-659页

作者： ZHANG YuXiu1,2, ZHANG KaiJun1,3, LI Bing1,2, WANG Yang1,2, WEI QingGuo1,2 & TANG XianChun1,2 1 Key Laboratory of Marginal Sea Geology, Guangzhou Institute of Geochemistry, Chinese Academy of sciences, Guangzhou 510640, china 2 Graduate university, Chinese Academy of sciences, Beijing 100039, china 3 department of earth sciences, nanjing university, nanjing 210093, china Key Laboratory of Marginal Sea Geology Guangzhou Institute of GeochemistryChinese Academy of Sciences Guangzhou 510640 China

地关系与 petrographical 一起， petrological ，和 geochemicalcharacteristics ，和锆石人口，显示从在 Bangong-Nujiang 缝术地区的 Lagkor Lakeophiolite 的 plagiogranites (～ Gerze 县的 20 km 南方，中央西藏，中国)，由在海洋的外壳的运输期间的可锻的砍源于含水的斑粝岩的 anatexis 。因此，这种 plagiogranite 比传播海洋的外壳晚对或很少同时代。锆石虾 166 ±使 2.5 妈变老因为 plagiogranites 显示海洋的盆在中间的侏罗记在 Bangong-Nujiang 地区的西方的部分存在。

关键词：西藏改则县拉果错湖泊蛇绿岩斜长花岗岩锆SHRIMP U-Pb地质年代岩石成因

Distribution characteristics of terrestrial heat flow density in Jiyang depression of Shengli Oilfield, East china

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Science china earth sciences 2004年第9期47卷 804-812页

作者： GONG Yuling1,2, WANG Liangshu1, LIU Shaowen1, LI Cheng1, HAN Yongbing1, LI Hua1, LIU Bo1 & CAI Jingong3 1. department of earth sciences, nanjing university, nanjing 210093, china 2. department of Exploration and Information Technology of East china Institute of Technology, Fuzhou 344000, china 3. earth Science Institution of Shengli Oilfield, Dongying 257015, china department of earth sciences Nanjing University Nanjing 210093 China department of Exploration and Information Technology of East china Institute of Technology Fuzhou 344000 China earth Science Institution of Shengli Oilfield Dongying 257015 China

Based on the geo-temperature data of 13 systematically continuous temperature log curves and 700 testing oil boreholes in Jiyang depression, Shengli Oilfield, and the measured thermal conductivities of 47 rock samples, the terrestrial heat flow densities of 114 boreholes of Jiyang depression and its surrounding areas are determined, including 13 of those data derived from systemically continuous temperature logging. The results show that Jiyang depression has a relatively high background heat flow with an average value (65.8 5.4) mW/m2. The lateral variation of heat flow in basin has negative correlation with basement depth. Moreover, heat flow of uplift areas with shallower basement is high, so are those of regions with volcanic rocks, and those of depression areas with deep basement are relatively low. The heat flow densities of different structural units of Jiyang depression can be summarized as follows: The average heat flow value of Zhanhua sag is (67.4 5.3) mW/m2, higher than that of the whole basin, that of Dongying sag is (66.0 6.1) mW/m2, and that of Chezhen sag is (65.1 3.7) mW/m2. It is apparent that these latter two values are approximate to the average value of the whole Jiyang depression, while the average value of Huimin sag is (63.65.0) mW/m2, lower than that of the whole basin. In fact, the basement depth and the distribution framework of uplift and depression areas are all controlled by the process of lithosphere extension. In addition, the distribution of volcanic rocks in basin is also relatively close to this extension geodynamic process. In summary, the distribution characteristics of terrestrial heat flow of Jiyang depression is determined by the Cenozoic tectono-thermal events of this region.

关键词： Jiyang depression, terrestrial heat flow, thermal conductivity.

Geochemistry of Trace and Rare earth Elements in Red Soils from the Dongting Lake Area and Its Environmental Significance

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Pedosphere 2009年第5期19卷 615-622页

作者： MAO Long-Jiang MO Duo-Wen YANG Jing-Hong SHI Chen-Xi College of Atmospheric Science Nanjing University of Information Science & Technology Nanjing 210044 (China) College of Urban and Environmental sciences Peking University Beijing 100871 (China) department of earth sciences Nanjing University Nanjing 210093 (China)

Trace element(TE) and rare earth element(REE) contents in red soils from the Dongting Lake area of china were determined to understanding the provenance and weathering characteristics of the red *** results showed similar REE distribution patterns among red soils from the Dongting Lake area,Xiashu loess from Zhenjiang,loess and Pliocene red soil from the Loess *** patterns implied a similar provenance from dust-storms,except for red soil R5 which formed by bedrock weathering and had significant light REE(LREE) enrichment and heavy REE(HREE) depletion due to longer weathering periods and higher intensity of *** element,especially the Rb/Sr and Li/Ba ratios,and REE,especially the LREE/HREE ratio and δEu could trace weathering *** Rb/Sr,Li/Ba,and LREE/HREE ratios and negative Eu anomalies were present in the red soils from the Dongting Lake *** weathering intensity was in the decreasing order of R5 in the Dongting Lake area > red soils from the Dongting Lake area(including reticulate red soil,weak reticulate red soil,and homogeneous red soil formed by dust storms) > Xiashu loess from Zhenjiang > loess-paleosol and Pliocene red soil from the Loess *** in the TE and REE contents of soil could be effectively used to study the provenance and the weathering intensity.

关键词： Hunan Province provenance sedimentary processes weathering intensity

CO_2 Density-Raman Shift Relation Derived from Synthetic Inclusions in Fused Silica Capillaries and Applications

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地学前缘 2009年第S1期16卷 165-166页

作者： Yucai Song,I-Ming Chou,Wenxuan Hu 1.Institute of Geology,Chinese Academy of Geological sciences,Beijing 100037,china. 2.U.S.Geological Survey,National Center,Reston VA 20192,U.S.A. 3.department of earth sciences,nanjing university,nanjing 210093,china

The density of CO2 inclusions in minerals is commonly used to determine the crystallizing conditions of the host ***,the conventional microthermometry method is difficult to apply for inclusions that are small in size... 详细信息

关键词： synthetic fluid inclusion fused silica capillary CO2 inclusion CO2 density equation Raman analysis

Depth zonation of Arenigian acritarchs in South china

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Chinese Science Bulletin 1997年第3期42卷 248-251页

作者： XU Wanhongdepartment of earth sciences, nanjing university, nanjing 210093, china department of earth sciences Nanjing University Nanjing China

STAPLIN revealed that palaeoenvironment changes seem to control acritarch distribution patterns. However, scientists have been puzzled by the fact that characteristic offshore acritarchs occur with nearshore ones. This note demonstrates depth zonation of Arenigian acritarchs in South china and reveals the variation of water depth in South china during the Arenig Age.

关键词： South china Arenigian acritarch depth zonation.

Magnetic fabrics in fault-related fold and its relation with finite strain: an example from Mingjiang thrust structures in Western Sichuan

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Progress in Natural Science:Materials International 2007年第5期17卷 551-558页

作者： Jia Dong, Chen Zhuxin, Luo Liang, Hu Qianwei and Jia Qiupeng (department of earth sciences, nanjing university, nanjing 210093, china) [a]department of earth sciences Nanjing University Nanjing China

The anisotropy of magnetic susceptibility (AMS) is a quick, effective and sensitive technique used to measure the weakly deformed sedimentary rocks, and also a reliable method to reveal the deforming mechanisms of fault-related folds. In Longmenshan front belt, a typical cross-section of fault-related folds is chosen to study the AMS. A total of 224 oriented specimens have been drilled at 23 different sampling sites which were distributed at the key structural positions of this structural section developed in the Xujiahe formation of the upper Triassic. Six elementary types of magnetic fabrics are recognized and established through this AMS study: Da sedimentary fabric; 2) an initial deformation fabric; 3) a pencil structure fabric; 4) a weak cleavage fabric; 5) a strong cleavage fabric; 6) a stretching lineation fabric. It has been found that most of magnetic fabrics are characterized by fabrics of weak deformation which belong to the pure-shear results of a pre-folding layer parallel shortening (LPS). In the fault-bend fold, almost all magnetic fabrics are the initial deformation fabrics of weak deformation, and denote that the deformation in the forelimb is stronger than that in the backlimb and no finite strain is shown in the footwall. While in the fault-propagation fold, finite strains are concentrated in the trishear zone where magnetic fabric results are approximately consistent with the estimated consequences of the kinematic model. The tectonic stress field indicated by the magnetic fabrics is basically the same along the whole structural section and shows a NW to SE compression and shortening which is accordant with the regional compressive stress field of the Longmenshan fold-thrust belt.

关键词： magnetic fabric finite strain fault-related fold trishear zone Longmenshan.

(1.2)INVERSES OF OPERATORS BETWEEN BANACH SPACES AND LOCAL CONJUGACY THEOREM

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Chinese Annals of Mathematics,Series B 1999年第1期20卷 57-62页

作者： MA JIPU(department of Mathematics,nanjing university,nanjing 210093,china) nanjing Univ Dept Math Nanjing 210093 Peoples R China

Let E and F be Banach spaces and f non-linear C1 map from E into F. The main result isTheorem 2.2, in which a connection between local conjugacy problem of f at x0E and a localfine property of f'(x) at x0(see the Definition 1.1 in this paper) are obtained. This theoremincludes as special cases the two known theorems: the finite rank theorem and Berger's Theoremfor non-linear Fredholm operators. Moreover, the thcorem gives rise the further results for somenon-linear semi-Fredholm maps and for all non-linear semi-Wedholm maps when E and F areHilbert spaces. Thus Theorem 2.2 not only just unifies the above known theorems but alsoreally generalizes them.

关键词： Nonlinear semi-Fredholm maps Conjugacy problem Banach space