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Zircon SHRIMP U-Pb dating for the Cangshuipu volcanic rocks and its implications for the lower boundary age of the Nanhua strata in South china

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Science Bulletin 2003年第16期48卷 1663-1669页

作者： WANG Jian1, LI Xianhua2. DUAN Taizhong3. LIU Dunyi4, SONG Biao4, LI Zhongxiong1 & GAO Yonghua5 1. Chengdu institute of Geology and {2. resources,{3. Geologi-cal Survey, Chengdu 610082.{3. 2. Guangzhou institute of Geochemistry, Chinese academy of Sciences, Guangzhou 510640,{3. 3. Colorado School of Mines, Golden, CO 80401-1887, USA (Present address: Marathon Oil Company, Houston, TX 77056-2.2., USA) 4. institute of Geology, Chinese academy of {12. Sciences, Bei-jing 10003.,{3. 5. Graduate School of the Chinese academy of {12. Sciences, beijing 10003.,{3. Correspondence should be addressed to Wang Jian (e-mail: jianwang@ ***) Chengdu institute of Geology and mineral {2. China Geological Survey Chengdu China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China Colorado School of Mines Golden USA institute of Geology Chinese Academy of Geological Sciences Beijing China Graduate School of the Chinese academy of geological Sciences Beijing China

The continental volcanic rocks and volcaniclas-tic sedimentary conglomerates of the Cangshuipu Formation occur well in Yiyang of Hunan Province, consisting of a wedge-shaped succession of Neoproterozoic strata that over-lie with high-angle unconformity the flysch turbidites of the Lengjiaxi Group in the Upper Mesoproterozoic Eonothem. SHRIMP zircon U-Pb dating gives a weighted mean age of 814 12.Ma for the dacitic volcanic agglomerates from the lowest part of the volcanic rocks in the Cangshuipu Forma-tion. This age is younger than previously reported values of 92.—93. Ma for the volcanic rocks from the Cangshuipu Formation. Our new dating represents the lower boundary age of the Neoproterozoic System in the studied area. The younger age for the Cangshuipu volcanic rocks is supported by the following observations: （1） Lower Neoproterozoic strata （814—1000 Ma） are missing in the studied area; （2. the Nanhua rift system was initiated at about 82. Ma; and （3. an age of82. Ma may be taken as the lower boundary tim-ing of the Nanhua System （even Neoproterozoic） in South{2..

关键词： Zicon U-Pb dating Neoproterozoic volcanics rift basin Nanhua System.

Simulating the impacts of climate variation and land-cover changes on basin hydrology: A case study of the Suomo basin

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Science china Earth Sciences 2005年第9期48卷 1501-1509页

作者： CHEN Junfeng1,2. LI Xiubin2.& ZHANG Ming2.1. institute of Remote Sensing & GIS, Peking University, beijing 100871,{2. 2. institute of Geographical Sciences and Natural resources Research, Chinese academy of Sciences, beijing 100101,{2. institute of Remote Sensing & GIS Peking University Beijing China institute of Geographical Sciences and Natural resources Research Chinese Academy of Sciences Beijing Chin

Impacts of land cover changes on watershed hydrology have been a long-term academic concern with acute dispute. But little attention has been paid to such effects on mesoscale river basins, where the society has a closer link to river hydrology. The present study focuses on a mesoscale river basin, the Suomo Basin that is located on the upper reaches of the Yangtze River. Land covers in the basin in the years 1970, 1986 and 1999 were mapped. A lumped hydrologic model, CHARM, and a distributed hydrologic model, SWAT, were used to model the impacts of both land-cover change and climate variation on river runoff during the past four decades. The results show that the contribution of climate variation to the change of runoff regime makes up 60%―80%, while that of land cover changes only 2.%.

关键词： climate variation, land-cover changes, Suomo Basin, CHARM model, SWAT model.

The tectonic settings and seismogenic tectonics of the M5.7 Jiujiang earthquake in 2.05,Jiangxi Province,china

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Science china Earth Sciences 2008年第5期51卷 640-653页

作者： LI ChuanYou1, ZENG XinFu2.& ZHANG JianXi3.1 institute of Geology,{2. Earthquake Administration, beijing 10002.,{2. 2.Jiangxi Earthquake Administration, Nanchang 3.003.,{2. 3.beijing Earthquake Administration, beijing 100080,{2. institute of Geology China Earthquake Administration Beijing China Jiangxi Earthquake Administration Nanchang China beijing Earthquake Administration Beijing China

The M5.7 Jiujiang earthquake in 2.05 was a mid-strong one, stronger than expected to occur in the region. This paper discusses the neo-tectonic settings of this earthquake, and it is thought that the earthquake region is located in the transitional belt, a potential area inducing weak to moderately strong earthquakes, between two large different tectonic units. The results of the reconnaissance work and on-the-spot investigation after earthquake indicate that the occurrence of the M5.7 Jiujiang earth- quake is closely related with the NE-trending fault on the western margin of Ruichang Basin. From its controlling to the landforms and Quaternary depositions, geological profiles, ESR dating, etc., the ac- tivity of the Dingjiashan-Langjunshan fault bounding the basin is discussed. It suggests that this fault displays an active one in Middle Pleistocene by the outcrop. Based on the activity of the fault, and the direction and location of the ground fissures, the isoseismal lines and the nodal plane of the focal mechanism solution, it is inferred that the Dingjiashan-Langjunshan fault is the seismogenic tectonics of the M5.7 Jiujiang earthquake, and the intersection point between this fault and the active NW ones is the possible origin of location of this earthquake. Our study shows that this earthquake is not an event exceeding expectation, and that the active and invisible characteristics of the causative fault are typical in the eastern area of china.

关键词： Jiujiang earthquake tectonic settings Dingjiashan-Langjunshan fault activity seismogenic tectonics

Evaluation of 10 plant barcodes in Bryophyta (Mosses)

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Journal of Systematics and Evolution 2010年第1期48卷 36-46页

作者： 1,2.Yan LIU 3.Hai-Fei YAN 4 Tong CAO 3.Xue-Jun GE 1({2. of Applied Ecology, Chinese academy of Sciences, Shenyang 110016, china) 2.Graduate University of the Chinese academy of Sciences, beijing 100049, china) 3.Key Laboratory of Plant resources Conservation and Sustainable Utilization, South china Botanical Garden, Chinese academy of Sciences, Guangzhou 510650, china) 4(College of Life & Environment Sciences, Shanghai Normal University, Shanghai 2.02.0}, china) (institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China) (Graduate University of the Chinese academy of Sciences Beijing 100049 China) (Key Laboratory of Plant resources Conservation and Sustainable Utilization South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China) (College of Life & Environment Sciences Shanghai Normal University Shanghai 200234 China)

DNA barcoding is a molecular tool that uses a standardized DNA region to identify *** preliminary study reported here is the first attempt to specifically focus on universality and attributes of candidate barcodes across a wide systematic range of *** tested eight previously proposed plant barcoding regions(atpF-atpH, ITS2. matK, psbK-psbI, rbcL, rpoB, rpoC1, and trnH-psbA) and two popular phylogenetic markers(rps4 and trnL-trnF of cpDNA) in 49 moss species and 9 liverwort species, representing half of the orders in moss *** ITS2. rbcL, rpoC1, rps4, trnH-psbA and trnL-trnF regions showed good universality, and therefore the efficacy of these loci as DNA barcodes was further evaluated in 3. mosses and 2.liverworts, each of which included two to three individuals per *** five loci, ***, rpoC1, rps4, trnH-psbA and trnL-trnF, were easy to amplify and sequence and showed significant inter-specific genetic variability, making them potentially useful DNA barcodes for *** best performing single loci were the rbcL and rpoC1 coding *** loci showed equivalent performance and combinations of them did not greatly increase their discrimination *** addition, phylogenies generated from each of the separate regions and multi-locus combinations by using best-fit and Kimura 2.parameter models were compared, but no significant difference was found.

关键词： Bryophyta DNA barcoding rbcL rpoC1 rps4 trnH-psbA trnL-trnF.

Sorption behavior of U(VI), ^(2.0})U(VI) and ^(2.0})U(VI) onto fracture-filling clays in Beishan granite, Gansu: Application to selecting the site of high-level radwaste repository in{2.

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Science china Earth Sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1,2. LUO Xingzhang3. WANG Ju4, JIN Yuanxin4 & WANG Rucheng1 1. Department of Earth Sciences, State Key Laboratory of mineral Deposit Research, Nanjing University, Nanjing 2.0093. china 2. Center of Materials Analysis, Nanjing University, Nanjing 2.0093. china 3. Department of Environmental Science and Engineering, Nanjing University, Nanjing 2.0093. china 4. beijing Geology institute, Nuclear Industry, beijing 10002., china Nanjing University Nuclear Industry

The first results of sorption experiments of U(VI), 2.0}U(VI) and 2.0}U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province,{2. are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in{2.. The present experimental results show that the maximum U(VI) sorption reached 92. at near-neutral pH and the distribution coefficient (Kd) was 12.6 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep geological disposal repository. No preferential sorption of 2.0}U onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.

Analysis on the Dynamical Process of Donghekou Rockslide-Debris Flow Triggered by 5.12.Wenchuan Earthquake

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Journal of Mountain Science 2011年第2期8卷 140-148页

作者： SUN Ping ZHANG Yongshuang SHI Jusong CHEN Liwei Key Laboratory of Neotectonic Movement & Geohazard Ministry of Land and Resources Beijing China institute of Geomechanics Chinese Academy of Geological Sciences Beijing China china Nuclear Power Engineering Corporation Ltd. Beijing China

Among the geo-hazards caused by the great Wenchuan Earthquake, the rapid and long runout rockslide-debris flow is of primary concern due to the large volume of displaced material and the resultant catastrophic impacts to the landscape and socioeconomic structure. In order to analyze the dynamical process of this kind of geo-hazard, the Donghekou rockslide-debris flow is given as an example in this paper. This event, which killed 780 people, initiated at an elevation of 13.0 m with a total long run-out distance of more than 2.00 m. The slide mass is mainly composed of dolomite limestone and siliceous limestone of Sinian system, together with carbon slate and phyllite of Cambrian. During the processes from slide initiation to the final cessation of slide movement, five dynamic stages took place, here identified as the initiation stage, the acceleration of movement stage, the air-blast effect stage, the impact and redirection stage and the long runout slidematerial accumulation stage. Field investigations indicate that due to the effects of the earthquake, the dynamics of the Donghekou rockslide-debris flow are apparently controlled by geologic and tectonic conditions, the local geomorphological aspects of the terrain, and the microstructural and macroscopic mechanical properties of rocks which compose the slide mass. These three main factors which dictate the Donghekou rockslide-debris flow dynamics are discussed in detail in this paper, and significant results of field investigations and tests of materials are presented. The above dynamical processes are analyzed in this paper, and some useful conclusions have been gained.

关键词： Dynamical process Donghekou Rockslide-debris flow Wenchuan earthquake

A new species of Leptocycas (Zamiaceae) from the Upper Triassic sediments of Liaoning Province,china

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Journal of Systematics and Evolution 2010年第4期48卷 286-301页

作者： 1,2.3.ian-Wei ZHANG 2.ian-Xin YAO 1Jia-Rui CHEN 1Cheng-Sen LI 1(State Key Laboratory of Systematic and Evolutionary Botany,institute of Botany,Chinese {2. of Sciences,beijing 100093.{3.) 2.State Key Laboratory of Stratigraphy and Paleontology,institute of Geology,Chinese {2. of geological Sciences,beijing 10003.,{3.) 3.Graduate University,Chinese {2. of Sciences,beijing 100049,{3.) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (State Key Laboratory of Stratigraphy and Paleontology Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China) (Graduate University Chinese Academy of Sciences Beijing 100049 China)

A new cycad,Leptocycas yangcaogouensis ***.,was found in sediments from the Late Triassic in western Liaoning,*** pinnately compound leaves(Pseudoctenis type)are screwed in a crown on the stem *** leaflets are linear,with parallel veins and decurrent bases on the *** leaf bases are *** cataphylls intermix with the *** female cone is ovoid in *** characteristics of the new plant are more similar to those of Leptocycas gracilis,a Triassic cycad from North America,but the new species differs from *** in the size of its stem(7–8 vs.3.5 cm in diameter,respectively),leaves(length×width 100×16 vs.3.×7 cm,respectively)and leaf density along the stem(4–6 vs.1–2.bases/1 cm length,respectively).Both *** and ***,having leaves of the Pseudoctenis type,show a closer relationship to the extant Dioon of *** present study provides evidence for the origin of the genus Dioon,which may have come from Leptocycas plants of the *** would be assumed that the extent cycads in Zamiaceae originate from the pteridosperms in the Late Paleozoic and have evolved through the stage of *** and *** in Late Triassic,and reaching the extant Dioon.

关键词： china Cycadales Leptocycas Upper Triassic Zamiaceae

SHRIMP zircon U-Pb age and Nd isotopic study on the Nyainqêntanglha Group in Tibet

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Science china Earth Sciences 2005年第9期48卷 1377-1386页

作者： HU Daogong1, WU Zhenhan1, JIANG Wan1, SHI Yuruo2. YE Peisheng1 & LIU Qisheng1 1. institute of Geomechanics, Chinese academy of {2. Sciences, {3. 100081, china 2. institute of Geology, Chinese academy of {2. Sciences, {3. SHRIMP Centre, beijing 10003., china institute of Geomechanics Chinese Academy of Geological Sciences Beijing China institute of Geology Chinese Academy of Geological Sciences Beijing SHRIMP Centre Beijing China

The Nyainqêntanglha Group is traditionally viewed as the oldest metamorphic basement in the Lhasa block, but its formation age and tectonic setting remain debate. Zircons extracted from the metamorphic sequence of volcanics and intrusions of the Nyainqêntanglha Group, 10 km west of Nam Co in northern Lhasa block, have been investigated by cathodolu- minescence (CL), backscattered (BSE) and dated by ion microprobe (SHRIMP). We conclude that the U-Pb age of 787±9 Ma of zircons from the trondhjemite imposes a constraint on maxi- mum protolith age, and minimum formation age of the Nyainqêntanglha Group is constrained by U-Pb age of 748±8 Ma of zircons from the granite. The formation age of the Nyainqêntanglha Group is consistent with sedimentary age of Greater Himalayan rocks, showing that they devel- oped coevally in an arc-basin tectonic setting of Neoproterozoic active continental margin along the northern margin of the India shield. The inherited zircons from the tholetiite and granite give older 2.7Pb/2.6Pb ages from 947 to 1766 Ma. The positive εNd( t ) value indicates that the mafic rocks were derived from the depleted mantle, but contaminated by the older continental crustal material. Integrated Nd model age and U-Pb age data provide excellent evidence for the exis- tence of Mesoproterozoic basement in the Lhasa block during Neoproterozoic time.

关键词： Nyainqêntanglha Group, SHRIMP dating, Nd isotope, Neoproterozoic, Tibet.

Vermicular fossils in the Early Cambrian Xidashan Formation in the Quruqtagh region of Xinjiang, china

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Progress in Natural Science:Materials International 2006年第5期16卷 559-562页

作者： YANG Ruidong, ZHANG Chuanlin, SONG Guoqi and LUO Xinrong (Postgraduate School of Guizhou University, Guiyang 55002., china Nanjing institute of Geology and {2. {3., Nanjing 2.0016, china geological Survey of No. 3.geological Party, Xinjiang, Kurle 841000, china) Postgraduate School of Guizhou University Guiyang 550025 China Nanjing institute of Geology and mineral {2. Nanjing 210016 China geological Survey of No. 3.geological Party Xinjiang Kurle 841000 China

Large amounts of vermicular fossils and a minor amount of sponge animal fossils have been found in the Early Cambrian Xidashan Formation in the region of Quruqtagh, Xinjiang. Vermicular fossils are generally more than 50 mm long and 0. 3.1. 4 mm wide; their wrinkled lamellae are microfine with 3.10 pieces within the length of every each millimeter. The fossils are considered to be Sabellidites cambriensis Sokolov (1965) . The Xidashan Formation is the highest stratum in which Sabellidites occur, as has been so far reported.

关键词： vermicular fossil Early Cambrian Quruqtagh Xinjiang.