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Location of Triassic Tectonic Suture Between Collided Sino-Korean and Yangtze Cratons in Dabie-Sulu Region, china

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Journal of earth Science 1999年第4期18卷 281-286页

作者： Suo Shutian Zhong Zengqiu You Zhendong(faculty of earth {2.,{3., Wuhan 43.074) faculty of earth {2. China University of GeosciencesWuhan 430074

The regional extent and spatial distribution of ultrahigh pressure metamorphic(UHPM) and high pressure metamorphic (HPM) rocks, and the geometrical relationships of various petrotectonic units in the Dabie-Sulu region indicate that the Triassic collisional suture line between the Sino-Korean and Yangtze cratons is situated at the northern margin of the Dabie massif, that is,along the Balifan-Mozitan-Xiaotian fault in the Dabie region, and possibly is linked to the Wulian-Yantai fault in the Sulu region to tbe east. The suture line has been strongly modified duriug and subsequent to UHPM aud HPM events.

关键词： UHPM and HPM belts suture line Dabie massif Dabie-Sulu region

Permian and Triassic Sequence Stratigraphy and Sea Level Changes of Eastern Yangtze Platform

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Journal of earth Science 1999年第2期18卷 71-79页

作者： Tong Jinnan Yin Hongfu Zhang Kexin faculty of earth {2.,{3., Wuhan 43.074

The Permian and marine Triassic of eastern Yangtze platform, situated in eastern china, involve 19 orthosequences lasting about 2.7 Ma on average, which can be combined into five orthosequence sets ranging from 8 Ma to 12.Ma. Affected by the regional Dongwu and Indosinian movements, the sequence stratigraphic pattern and sea level changes in the Permian and Triassic of this region are distinctive and obviously different from most other regions in the world, but typical in the broad eastern Tethys and its neighboring areas. In this region not only did the continuous marine Permian and Triassic boundary sequences cause the orthosequence crossing the boundary belonging to type Ⅱ sequence but also the mesosequence including these stratigraphic intervals had its basal boundary in the upper Longlinian (Artinskian) (ca. 2.8 Ma), that is, the traditional Carboniferous and Permian boundary, and its top boundary moved from the Permian and Triassic boundary upward into the Anisian of Middle Triassic.

关键词： Permian and Triassic sequence stratigraphy sea level change eastern Yangtze platform.

Peat molecular fossils recording paleoclimatic change and organism replacement

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Chinese Science Bulletin 2001年第20期46卷 1749-1752页

作者： XIE Shucheng & R. P. Evershed1. faculty of earth Science,{2., Wuhan 43.074,{3. 2. School of Chemistry, university of Bristol, Bristol, BS8 1TS, UK Correspondence should be addressed to Xie Shucheng (e-mail: scxie@ ***) faculty of earth Science China University of Geosciences Wuhan China School of Chemistry University of Bristol Bristol

The occurrence of the dominant C2.0}n-alkane derived from bryophyte was demonstrated to be related to the cold climate, based on the GC and GC/MS analyses on a 40-cm long peat core, in which this compound exponentially varies in abundance with the depth corresponding to the well-known second Little Ice Age. Both the variation of the chemical components of modern bryophyte resulted from climatic change and the ecological data about the biological growth influenced by climate shed light on the point that the variation of this compound in the peat was related to the cold climate. This was also evidenced by the previously-reported lacustrine data. In addition, the variations of the ratios of ketones/esters and C2. n-alkene/n-alkane (C2.:1/02.:0) display the trend identical with that of organisms, implicating the replacement between bryophyte and monocotyledon occurring in the peat core.

关键词： bryophyte molecular fossil n-alkane paleoclimate Little Ice Age peat lacustrine.

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,{2. 2.Graduate {2., Chinese Academy of sciences, Beijing 10003.,{2. 3.Department of earth sciences, Nanjing {2., Nanjing 2.0093.{2. 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 2. 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

Characteristics of Bacillus cereus Spore Counts in Soils w ith Underlying Gold Mineralization in Northwestern Sichuan, china: Results from a Pilot Study

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Journal of china university of geosciences 2003年第1期14卷 8-15页

作者： Wang Hongmei Yang Fengqing Qiao Shengying faculty of earth {2.,{3., Wuhan 43.074 faculty of earth {2. China University of GeosciencesWuhan 430074

A pilot survey on a microbial mineral exploration method based on so il Bacillus cereus spore counts was carried out across three different gold mi ning regions, which vary in soil type, climate condition and geological setting in northwestern Sichuan, china. B horizon soils from these sites were analyzed for B. cereus spores, Au, Ag, Cu, Pb and Zn. The results show that the numbe rs of B. cereus spores generally increased in soils overlying gold mineraliz ation. Specifically, elevated spore counts were found in samples slightly offset from the outcrops of orebodies, whereas soils directly above the outcrops of or ebodies usually contained low spore counts. However, the background counts of B. cereus spores varied from place to place and were complicated by environmen tal and pedological factors, but the relative ratios of spore counts still were indicative of the underlying gold mineralization.

关键词： Bacillus cereus spores gold deposit soil china.

Differentiation of Natural and Irradiated Blue Topaz by Cathodoluminescence(CL) Properties

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地学前缘 2009年第S1期16卷 169-170页

作者： Ying Song~(1,2.,Xinqiang Yuan~2.1.faculty of earth Resources,{2. {3. of geosciences(Wuhan),Wuhan 43.074,{2.. 2.Gemmological Institute,{2. {3. of geosciences(Wuhan),Wuhan 43.074,{2.

Blue colored topaz is one of the most recognized gemstones ***,it is rarely found in the field and the products have been made mostly in laboratory using gamma,neutron and electron irradiation or combinations of these *** of the blue color in topaz remains not well understood, largely due to a lack of nondestructive way in idnetifying the blue *** we report a compari-

关键词： cathodoluminescence natural blue topaz irradiated blue topaz

Numerical simulations of the bi-level and branched structure of intracloud lightning flashes

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Science china earth {2. 2006年第6期49卷 661-672页

作者： TAN Yongbo1, TAO Shanchang1, ZHU Baoyou1, MA Ming2.& LU Weitao2.1. School of earth and Space sciences, {2. of Science and Technology of{3., Hefei 2.3}02.,{3. 2. Chinese Academy of Meteorological sciences, Beijing 100081,{3. 1. School of earth and Space sciences University of Science and Technology of China Hefei 230026 China 2. Chinese Academy of Meteorological sciences Beijing 100081 China

Intracloud (IC) lightning flashes have been simulated in fine resolution (12.5 m) by using a bidirectional stochastic lightning parameterization scheme within 2.dimensional domain. The simu-lated results show that the IC flashes have a bilevel channel structure and the altitudes of the hori-zontal channels are at the same heights of potential wells, which are supported by the previous VHF source observations and balloon soundings of electric field profile in the thundercloud. Further con-clusions are: (1) After an IC flash is initiated near the boundary between positve and nagetive charge zone, the negative (or positive) leader tends to propagate into the positive (or negative) charge zone. Both types of positive and negative IC flashes have been reproduced and their polarity depends on the up and down disposition of the positive and negative charge regions. (2. The extension range of leaders is correlative with the cloud charge distribution. The leader is possible to extend through the inverted charge region all over where it is extending, but keeps away from the isolated charge area of the same polarity. (3. The channel structures also depend on the electric potential distributions in the thundercloud. Before propagating into the central area of potential wells, the leader tends to extend along the direction with the maximum of potential gradient. Once extending away from the center of potential wells, the leader tends to extend along the direction with the slowest potential change. (4) The IC flash channels have the fractal feature with fractal dimension 1.45 before leaders pass through the central area of charge regions. The exponent decreases rapidly once leaders extend into the low-density charge regions. (5) The induced charges of opposite polarity are deposited in the leader channels within preexisting positive and negative charge regions during IC flash discharges. This causes a new and complicated charge distribution in the thundercloud, and the potential

关键词： IC, lightning parameterization, branched bilevel structure, fractal feature, propagation tendency.

High-Field-Strength Elements in Mafic Volcanics from North china Craton: Implications for Archean-Proterozoic Boundary and Source Composition

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Journal of earth Science 1998年第2期17卷 17-23页

作者： Liu Yongsheng Gao Shan Luo Tingchuan faculty of earth {2.,{3., Wuhan 43.074

Archean to Cenozoic mafic volcanic rocks from the North china craton are studied. They show Archean Proterozoic (Ar Pt) boundary and geochemical anomalies in Cenozoic basalts. Proterozoic mafic volcanics are enriched in most of the high field strength elements (HFSE) compared with Archean ones. Nb, Ta and Th show a distinct sequence of incompatibility in Archean and Proterozoic. The Cenozoic basalts are enriched in HFSE and Ni and their REEs are strongly differentiated with positive Eu anomalies ( δ (Eu)=1.14). The Ar Pt boundary could be related to change in oxygen fugacity and requires an increasing importance of enriched mantle source. The geochemistry of Cenozoic basalts implies a mantle source similar to OIB. Residuum from subducting partial melting of old basaltic oceanic crust and continental crust is likely to contribute to the formation of the enriched mantle.

关键词： mafic volcanic rocks high field strength element Archean Proterozoic boundary enriched mantle.

Relic UHP Structures in Dabie-Sulu Region, china: Structural Expression and Geodynamic Significance

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Journal of earth Science 2000年第3期19卷 40-46页

作者： Suo Shutian Zhong Zengqiu You Zhendong Zhou Hanwen faculty of earth {2.,{3., Wuhan 43.074, china

The present day observed tectonic framework of ultrahigh pressure (UHP) metamorphic belt in the Dabie Sulu region was dominantly formed by an extensional process at 2.0-170 Ma, under amphibolite facies conditions, following the Triassic collision between the Sino Korean and Yangtze cratons. UHP relic structures, including massive eclogites with a weak foliation, UHP shear zones and A type folds, that are preserved in less retrograde metamorphism and deformation overprinted eclogite lenses can be recognized using the tectonic analysis. Examples are drawn from the Chengmagang area and Hejiawan area, Hubei; Bixiling area, Anhui, and Donghai area, northern Jiangsu. A speculative kinematic model is proposed for the collision between the cratons based on the UHP relic structures studied, in combination with the data of petrography, geochronology and P T path of UHP metamorphic rocks in the studied region which were reported in literature. It is stressed that only the early UHP relic structures, particularly, regionally consistent foliation and stretching lineations, record and reflect the formation of the UHP metamorphic rocks, and the relative dynamic and kinematic process related to the Triassic NNE directed oblique collision between the Sino Korean and Yangtze cratons.

关键词： UHP relic structure extensional process compressional regime stretching lineation Dabie Sulu region.