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A broad deglacial δ^(13)C minimum event in planktonic foraminiferal records in the Okinawa Trough

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Chinese Science Bulletin 2002年第7期47卷 599-603页

作者： LI Tiegang, LIU Zhenxia, M. A. Hall, Y. Saito, S. Berne, GANG Shuxi & CHENG ZhenboInstitute of Oceanology, Chinese Academy of Sciences, qingdao 2.6071, china The First Institute of Oceanography, State Oceanic Administration, {2. 2.6003, china Godwin I 1. Institute of Oceanology Chinese Academy of Sciences 266071 Qingdao China 2. The First Institute of Oceanography State Oceanic Administration 266003 Qingdao China 3. Godwin Institute for Quaternary Research University of Cambridge CB2 3RS Cambridge UK 4. geological survey of Japan 305-8567 Tsukuba Japan 5. French Oceanographic Institute IFREMER 29280 Plouzane France

The equatorial Pacific upwelling zone has been suspected of playing an important role in the global atmospheric CO2.changes associated with glacial-interglacial cycles. In order to assess the influencing scope of the surface water deglacial δ13C minimum in the tropical low-latitude Pacific, the core DGKS9603, collected from the middle Okinawa Trough, was examined for δ13C records of planktonic fo-raminifera N. dutertrei and G. ruber. The planktonic fo-raminiferal δ13C records show a clear decreasing event from 2. to 6 cal. kaBP., which is characterized by long duration of about 14 ka and amplitude shift of 0.4×10-3. Its minimum value occurred at 15.7 cal kaBP. The event shows fairly synchrony with the surface water deglacial δ13C minimum identified in the tropical Pacific and its marginal seas. Because there is no evidence in planktonic foraminiferal fauna and δ18O records for upwelling and river runoff enhancement, the broad deglacial δ13C minimum event in planktonic foraminiferal records

关键词： planktonic foraminiferal δ13C minimum event Oki-nawa Trough last deglaciation.

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东沙海区天然气水合物形成及分布的地质因素

石油学报 2004年第4期25卷 7-12页

作者：吴时国张光学郭常升黄永样钟少军中国科学院海洋研究所山东青岛266071 中国地质调查局广州海洋地质调查局广东广州510760

分析了东沙海区似海底反射波 (BSR)分布区的地质构造特征 ,以了解水合物的地质构造控制因素。似海底反射波通常被认为与水合物密切相关 ,主要出现在下陆坡沉积物碎屑流和浊流发育区 ,邻近在海陆过渡带 ,也是活动断裂构造密集发育和快速... 详细信息

分析了东沙海区似海底反射波 (BSR)分布区的地质构造特征 ,以了解水合物的地质构造控制因素。似海底反射波通常被认为与水合物密切相关 ,主要出现在下陆坡沉积物碎屑流和浊流发育区 ,邻近在海陆过渡带 ,也是活动断裂构造密集发育和快速沉积作用 (重力流沉积作用 )地区。该区位于被动大陆边缘 ,发育巨厚的沉积物。这些沉积物能够供应大量的流体 (天然气和水 ) ,在渗透性相对高的碎屑流和浊流沉积物中形成水合物。此外 ,沿洋陆壳过渡带 ,岩石圈热结构表现较高的热流值 ,容易形成似海底反射波。相反 ,在缺乏似海底反射波分布的广大上陆坡区。

关键词：东沙海区地质构造天然气水合物似海底反射波沉积作用活动断裂

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论鲁东地体的形成机制及其归属

海洋地质与第四纪地质 1989年第1期9卷 5-15页

作者：蔡乾忠地质矿产部海洋地质研究所

作者用地体说理论重新解释鲁东地区的胶东地块,认为是个外来地体——鲁东地体,不属于中朝地台范畴,应归属于扬子地台.作者指出鲁东地体与鲁西地块在基底变质程度、年代、地壳结构以及区域重磁特征等都有显著差异,在晚印支期鲁东地体才... 详细信息

作者用地体说理论重新解释鲁东地区的胶东地块,认为是个外来地体——鲁东地体,不属于中朝地台范畴,应归属于扬子地台.作者指出鲁东地体与鲁西地块在基底变质程度、年代、地壳结构以及区域重磁特征等都有显著差异,在晚印支期鲁东地体才从古太平洋陆块分裂位移到郯庐断裂,与鲁西地块发生热拼贴.

关键词：地体形成机制归属鲁东

DISCOVERY OF DIATOM ASSEMBLAGES FROM DEEP-SEA BASIN IN THE SOUTH china SEA AND THEIR geological IMPLICATION

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Acta Oceanologica Sinica 1987年第2期6卷 215-221页

作者：王开发蒋辉冯文科 Department of marine geology Tongji University Shanghai South china Sea Headquaters of geological {2. Ministry of geology and Mineral Resources Guangzhou

Of the diatoms from sediments of the South china Sea, mainly composed of planktonic species of tropical and subtropical zones, 36 genera and 86 species are identified. Based on the changes in diatom numbers and the appearance of diatom assemblages, six diatom zones are distinguished in Core V, reflecting six phases of paleoclimatc, paleo-watertemperature and paleogeography. According to the Quaternary climatic division, these zones represent hot weather and warm weather as a whole, and they are separately equal to postglacial period, the Holocene; Wurm glacial period; Riss-Wurm interglacial period; and Riss glacial period, the Late Pleistocene.

关键词： than more Th DISCOVERY OF DIATOM ASSEMBLAGES FROM DEEP-SEA BASIN IN THE SOUTH china SEA AND THEIR geological IMPLICATION SEA

A GIS Approach to Prediction of Copper Deposits

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Journal of Earth Science 2000年第2期19卷 88-90页

作者： Wu Xinlin Guangzhou marine geological {2., Guangzhou 510760 Chi Shundu Faculty of Earth Resources, china University of Geosciences, Wuhan 430074

This paper describes three main parts of GIS technique used in prospecting of copper deposits. Firstly, this paper briefly introduces GIS technique for data preparation. Then it discusses the geo anomaly (GA) analysis and targets delineation methods, where the unit ore equivalent calculation of planar GA and the transformation and evaluation of linear GA are dominant. In addition, the method for copper prospecting is demonstrated. Finally a case study of copper deposit prospecting in Yuanjiang, Yunnan Province is presented by the use of MAPGIS.

关键词： GIS GA copper deposits prognosis target area.

India Collided with Asia at Least 72.Ma:Recognition of An Underfilled Foreland Basin in Central Himalaya

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地学前缘 2009年第S1期16卷 271-272页

作者： Xiumian Hu,Jiangang Wang,Luba Jansa,Fuyuan Wu,Jinhai Yu 1.Department of Earth Sciences,Nanjing University,Nanjing 2.0093,china. 2.geological {2. of Canada-Atlantic,Dartmouth,N.S.,Canada 3.Institute of geology and Geophysics,Chinese Academy of Sciences Beijing 10002.,china

The Himalayan peripheral foreland basin developed when India and Asia *** studies in the Himalayan foreland were mostly concentrated on Neogene continental clastic sedimentation in sub-Himalaya or Paleogene shallow ma... 详细信息

关键词： Himalayan foreland underfilled foreland basin peripheral foreland

Geochronology of middle Neoproterozoic volcanic deposits in Yangtze Craton interior of South china and its implications to tectonic settings

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Science china Earth Sciences 2010年第9期53卷 1307-1315页

作者： WANG ZhengJiang1, WANG Jian1, DUAN TaiZhong2. XIE Yuan1, ZHUO JieWen1,3 & YANG Ping1 1 Chengdu Institute of geology and Mineral Resources, Ministry of Land and Resources, Chengdu 610082. china 2.Marathon Oil UK Ltd., Aberdeen, Scotland, AB15 6FZ, UK 3 Graduate Department, Chinese Academy of {2. Sciences, Beijing 100037, china 1. Chengdu Institute of geology and Mineral Resources Ministry of Land and Resources Chengdu 610082 China2. Marathon Oil UK Ltd. Aberdeen Scotland AB15 6FZ UK3. Graduate Department Chinese Academy of Geological Sciences Beijing 100037 China

Here we report new SHRIMP dating results of the crystal tuff in Ejiaao Formation of middle Banxi Group in northern Guizhou. The results indicate that the volcanic deposition occurred at ~780 Ma. We also suggests that the igneous activities across Yangtze Craton with diabase dyke swarms and basal volcanic rocks during middle Banxi time are indicative of the episodic, extensive and vigorous great bimodal igneous events during middle Neoproterozoic (82.-72. Ma) in South china. The characteristics of the igneous series are contrary to the model claiming they are of island-arc origin, but suggest that they are the records of rifting process and may be related to the episodic plume activities leading to the break-up of Rodinia.

关键词： Yangtze Craton middle Neoproterozoic Ejiaao Formation of Banxi Group SHRIMP zircon U-Pb dating episodic and bimodal igneous series

莱州湾及潍河口夏季浮游植物生物量和初级生产力的分布

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海洋学报 2002年第5期24卷 81-90页

作者：孙军刘东艳柴心玉钱树本青岛海洋大学海洋生命学院山东青岛266003 青岛海洋大学"东方红2.号调查船山东青岛266003

于 1 998年 6月黄河断流期在潍河口及其邻近海域进行了水文、化学和生物等专业综合外业调查 .对此海区浮游植物叶绿素a浓度、脱镁色素浓度和初级生产力的变化进行了分析 .研究结果表明 ,叶绿素a浓度介于 0 0 89～ 5 4 44mg/m3 之间 ,... 详细信息

于 1 998年 6月黄河断流期在潍河口及其邻近海域进行了水文、化学和生物等专业综合外业调查 .对此海区浮游植物叶绿素a浓度、脱镁色素浓度和初级生产力的变化进行了分析 .研究结果表明 ,叶绿素a浓度介于 0 0 89～ 5 4 44mg/m3 之间 ,平均值为 1 331mg/m3 ;脱镁色素浓度介于 0 1 76～ 3 4 0 2.g/m3 之间 ,平均值为0 90 5mg/m3 .叶绿素a和脱镁色素浓度高密度区分布在小清河口附近、潍河口内及潍河口以外临近海域 .初级生产力介于 1 3 58～ 30 1 54mg/ (d·m2.)之间 ,平均值为6 2. 4 9mg/ (d·m2.) .水柱初级生产力高值区分布在小清河口和 37 30°N ,1 1 9 4 7°E附近 .对水文、化学和浮游动物等环境因子与浮游植物生物量和初级生产力的相关性分析表明 ,整个调查区 ,浮游植物生物量和初级生产力与海区潮汐、光照、磷酸盐、硅酸盐和微型浮游动物等环境因子密切相关 ,同氨盐、硝酸盐和亚硝酸盐的作用不明显 ,其中潍河口内浮游植物的生物量分布同潮汐的关系最为密切 .夏季此海域浮游植物生长主要受磷酸盐和硅酸盐的限制 .

关键词：潍河口夏季生物量浮游植物叶绿素a 脱镁色素初级生产力渤海莱州湾

An accurately delineated Permian-Triassic Boundary in continental successions

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Science china Earth Sciences 2007年第9期50卷 1281-1292页

作者： YIN HongFu1, YANG FengQing2. YU JianXin2. PENG YuanQiao1, WANG ShangYan3 & ZHANG SuXin1 1 Laboratory of Biological and Environmental geology, china University of Geosciences, Wuhan 430074, china 2.State Key Laboratory of geological Process and Mineral Resources, china University of Geosciences, Wuhan 430074, china 3 geological survey of Guizhou Province, Guiyang 550011, china 1. Laboratory of Biological and Environmental geology China University of Geosciences Wuhan 430074 China 2. State Key Laboratory of geological Process and Mineral Resources China University of Geosciences Wuhan 430074 China 3. geological survey of Guizhou Province Guiyang 550011 China

The Permian-Triassic Boundary Stratigraphic Set (PTBST), characteristic of the GSSP section of Meishan and widespread in marine Permian-Triassic Boundary (PTB) sequences of South china, is used to trace and recognize the PTB in a continental sequence at Chahe (Beds 66f―68c). Diversified Permian plant fossils extended to the PTBST, and a few relicts survived above that level. Sporomorphs are dominated by fern spores of Permian nature below the PTBST, above which they are replaced by gymnosperm pollen of Triassic aspect. In the nearby Zhejue Section, the continental PTBST is charac- terized by the fungal 'spike' recorded in many places throughout the world. The boundary claybeds (66f and 68a,c) of the PTBST are composed of mixed illite-montmorillonite layers analogous with those at Meishan. They contain volcanogenic minerals such as β quartz and zircon. U/Pb dating of the upper claybed gives ages of 2.7.5 and 2.2.6 Ma for Beds 68a and 68c respectively, averaging 2.0 Ma. In con- trast to the situation in Xinjiang and South Africa, the sediment sequence of the Permian-Triassic tran- sition in the Chahe section (Beds 56―80) become finer upward. Shallowing and coarsening upward is not, therefore, characteristic of the Permian-Triassic transition everywhere. The occurrence of relicts of the Gigantopteris Flora in the Kayitou Fm. indicates that, unlike most marine biota, relicts of this pa- leophytic flora survived into the earliest Triassic. It is concluded that Bed 67 at Chahe corresponds to Bed 2. at Meishan, and that the PTB should be put within the 60-cm-thick Bed 67b④, now put at its base tentatively. This is the most accurate correlation of the PTB in continental facies with that in the marine GSSP.

关键词： Permian-Triassic Boundary, terrestrial sequence, U-Pb age, Chahe section, accuracy