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An overview of the crustal structure of the Tibetan plateau after 35 years of deep seismic soundings

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An overview of the crustal structure of the Tibetan plateau ...

中国科学院地质与地球物理研究所第11届（2.11年度）学术年会

作者： Zhongjie Zhang~(a,*),Yangfan Deng~(b,c),Jiwen Teng~a,Chunyong wang~d,Rui Gao~e,Yun Chen~a,Weiming Fan~b a State Key Laboratory of Lithospheric Evolution,institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 10002.,{2. b {2. institute of geochemistry,Chinese Academy of Sciences,guangzhou 510640,{2. c Graduate University of Chinese Academy of Sciences,Beijing 100049,{2. d institute of Geophysics,{2. Earthquake Administration,Beijing 100081,{2. e institute of Geology,Chinese Academy of Geological Sciences,Ministry of Land and Resources,Beijing 100037,{2.

Since the pioneer wide-angle seismic profile along the Yadong-Gulu rift acquired in 1974 by the ex-institute of Geophysics,Chinese Academy of Sciences(CAS),several research programs aimed to deep geophysics, performed thanks to the participation of Chinese national and international institutions,have been developed during last 35 years,including 2. wide-angle seismic profiles with total length of about 6000 *** profiles are unevenly distributed,most of them in eastern Tibet and few profiles in western *** this paper,we make a summarized presentation of all these wide-angle seismic profiles and provide an overall view of the seismic velocity structure of the crust beneath the broad Tibetan plateau, which is the product of the continuous convergence and collision of the Indian and Eurasian plates since about 50 Ma *** patterns of crustal thickness variation related to the tectonic blocks and along suture zones of the region are *** crust thickness is confirmed to be about 70-75 km under southern Tibet,and 60-65 km under northern,northeastern and southeastern *** leading edge of the subducted lithosphere reaches the northern margin of the plateau and directly contacts with Tarim *** of the 90°E boundary,the Indian crust is moving towards the northern edge of the plateau and collides with Tarim Basin at 80°E while reach the Bangong-Nujiang suture belt at 88°E;eastward of the 90°E boundary,the northern edge of the crust should be at 50-100 km south of Bangong-Nujiang *** results supply helpful constrains to understand the mechanism of the continent-continent collision and its consequences in the plateau and neighbouring areas.

关键词： Wide-angle seismic profiling Crustal thickness Tibetan plateau

SIMS U-Pb zircon geochronology of porphyry Cu-Au-(Mo) deposits in the Yangtze River Metallogenic Belt,eastern china:Magmatic response to early Cretaceous lithospheric extension

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SIMS U-Pb zircon geochronology of porphyry Cu-Au-(Mo) deposi...

中国科学院地质与地球物理研究所第十届(2.10年度)学术年会

作者： Xian-Hua Li~(a,*),Wu-Xian Li~b,Xuan-Ce wang~(a,c),Qiu-Li Li~a,Yu Liu~a,Guo-Qiang Tang~a, Yu-Ya Gao~a,Fu-Yuan Wu~a a State Key Laboratory of Lithospheric Evolution,institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 10002.,{2. b Key Laboratory of Isotope Geochronology and {2.,guangzhou institute of {2.,Chinese Academy of Sciences,guangzhou 510640,{2. c The institute for Geoscience Research,Department of Applied Geology,Curtin University of Technology,Perth,WA 6845,Australia

The middle-lower reaches of the Yangtze River is one of the most important metallogenic belts in china, hosting numerous Cu-Fe-Au-Mo *** chronological and geochemical investigations mostly focused on the magmatic rocks and associated deposits in the lower reaches of the river,but the timing and genesis of the Cu-Au-(Mo)mineralized porphyries in the middle reaches are yet to be well *** this study we carried out precise SIMS U-Pb zircon age determinations for a number of Cu-Au-(Mo) mineralized porphyries and barren granitoid intrusions in the Jiurui and Edong mining districts in the middle reaches of the Yangtze River *** new age results reveal two discrete magmatic and mineralization events at ca.145-146 Ma and ca.140 Ma in the study *** ca.145-146 Ma granitoids signify the start of the Cretaceous magmatism in the Yangtze River Metallogenic Belt,coinciding temporally with a regional tectonic switching from a Late Jurassic transpressive tectonic regime to an earliest Cretaceous extensional regime in eastern china.

关键词： SIMS U-Pb zircon geochronology Porphyry Cu-Au-(Mo)deposits Yangtze River Metallogenic Belt SE china

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热带东太平洋短柱样的放射虫地层学研究

微体古生物学报 2004年第3期21卷 227-236页

作者：王汝建叶瑛周怀阳刘传联同济大学海洋地质教育部重点实验室上海200092 浙江大学地球科学系杭州310012 中国科学院广州地球化学研究所广州510640

热带东太平洋 WS0 10 7和 WS990 1柱与东区 ES990 9柱放射虫地层学的研究显示 ,WS0 10 7和 WS990 1两柱深度 18— 19cm和 4— 5 cm以上的地层年龄小于 0 .2.1Ma,属于晚第四纪放射虫 Buccinosphaera invaginata带 (RN17)。在此深度处有... 详细信息

热带东太平洋 WS0 10 7和 WS990 1柱与东区 ES990 9柱放射虫地层学的研究显示 ,WS0 10 7和 WS990 1两柱深度 18— 19cm和 4— 5 cm以上的地层年龄小于 0 .2.1Ma,属于晚第四纪放射虫 Buccinosphaera invaginata带 (RN17)。在此深度处有一个大的沉积间断 ,缺失中新世、上新世和第四纪大部分地层。而在此沉积间断以下地层发现大量的渐新世 -始新世的放射虫 ,属渐新世最晚的放射虫 Lychnocanoma elongata带 (RP2.2.) ,年龄大于 2.3.6 2.Ma,而小于 2.4 .6 Ma。这两个柱放射虫含量变化也揭示了沉积间断的存在 ,说明沉积间断和放射虫含量的变化可以作为地层划分和对比的工具。 ES990 9柱的放射虫地层学研究发现 ,该柱地层年龄小于 0 .2.1Ma,属于晚第四纪放射虫Buccinosphaera invaginata带 (RN17)

关键词：放射虫地层学沉积间断多金属结核区热带东太平洋

geochemistry and Sr-Nd-Pb-Hf isotopes of Early Cretaceous basalts from the Great Xinggan Range,NE china:Implications for their origin and mantle source characteristics

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Geochemistry and Sr-Nd-Pb-Hf isotopes of Early Cretaceous ba...

中国科学院地质与地球物理研究所2.08学术年会

作者： Lian-chang Zhang~(a,*),Xin-hua Zhou~b,Ji-feng Ying~b,Fei wang~b,Feng Guo~c,Bo Wan~a,Zhi-guang Chen~a a Key Laboratory of Mineral Resources,institute of Geology and Geophysics,Chinese Academy of Sciences,P.O.BOX 982.,Beijing 10002.,{2. b State Key Laboratory of Lithospheric Evolution,institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 10002.,{2. c guangzhou institute of geochemistry,Chinese Academy of Sciences,guangzhou 510640,{2.

Late Mesozoic volcanism is widespread throughout northeastern china,mainly clustering in the Great Xinggan Range,where the major period of volcanic eruption was during the Early *** spatial distribution of volcanic rocks shows a NNE-extending *** lithology of Mesozoic basaltic rocks in the Great Xinggan Range ranges from trachytic basalts,basalts to basaltic *** the basis of lithological associations and spatial relationships,we divide the basalts into four groups,***,Genhe,Zalute and *** Early Cretaceous volcanism in the Great Xinggan Range is characterized by significant large ion lithophile elements(LILE) and light rare earth elements(LREE) enrichment and high field strength elements(HFSE) depletion,with a slightly enriched to depleted Nd-Hf and weakly enriched Sr isotopic compositions(initial Sr/Sr=0.7046-0.7079,ε(t)=+3,6 to - 6.9 andε(t)=+3.9 to -4.6).The Pb isotopic compositions are also variable with Pb/Pb,Pb/Pb and Pb/Pb values of 17.791-18.530,15.477-15.597 and 37.761-38.497,*** Sr-Nd-Pb-Hf isotopic data indicate that the rnagmatic sources are heterogeneous,showing an enriched to depleted signature of continental lithospheric *** rnagmatic sources of the Genhe and Zalute groups are characterized by mixing among PM,EM II and DM,whereas the Tahe and Xiwu groups derive from enriched lithospheric mantle that had experienced metasomatism by fluids or melts from subducted Paleo-Asian and Mongol-Okhotsk ocean slabs and possible influence of Precambrian *** Late Mesozoic volcanic rocks in the Great Xinggan Range resemble those of the Cenozoic calc-alkaline magmatism in the Basin and Range Province of the United *** therefore suggest that the widespread Mesozoic volcanic rocks in the Great Xinggan Range were generated in an extensional tectonic setting.

关键词： Element geochemistry Sr-Nd-Pb-Hf isotope Basaltic rocks Early Cretaceous Extensional setting Great Xinggan Range NE china

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珠海正坑小流域土壤与氮、磷养分流失估算

水土保持学报 2004年第1期18卷 100-102,114页

作者：吴志峰卓慕宁王继增匡耀求程炯广东省生态环境与土壤研究所广州510650 中国科学院广州地球化学研究所广州510630

土壤及土壤养分流失是农业非点源污染的主要形式。选择珠江三角洲地区典型小流域——正坑小流域为研究区,在GIS技术支持下,建立流域数字高程模型并获取下垫面相关参数,采用通用土壤流失方程、固态污染物负荷方程,进行小流域农业非点源... 详细信息

土壤及土壤养分流失是农业非点源污染的主要形式。选择珠江三角洲地区典型小流域——正坑小流域为研究区,在GIS技术支持下,建立流域数字高程模型并获取下垫面相关参数,采用通用土壤流失方程、固态污染物负荷方程,进行小流域农业非点源污染负荷估算与分析。结果表明,正坑小流域年土壤流失量为455061.60kg,旱坡地和果园两类土地利用景观类型具有相对较高的侵蚀模数;土壤N、P养分流失年负荷量分别为6335.32.1150.35kg,不同土地利用类型对非点源污染负荷的贡献率不同,水田中氮、磷流失对非点源污染负荷有重要影响。

关键词：珠海小流域土壤氮磷养分流失估算方法

Crustal anatexis in the intracontinental regime:Geochemical,zircon U-Pb geochronological and Hf isotopic fingerprints from the middle Paleozoic （Kwangsian） gneissic granites in the eastern South china Block

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Crustal anatexis in the intracontinental regime:Geochemical,...

中国矿物岩石地球化学学会第13届学术年会

作者： wang Yue-jun~(1,3),ZANG Ai-mei~1,FAN Wei-ming~1,ZHAO Guo-chun~(2.3), ZHANG Guo-wei~2.ZHANG Yu-zhi~1 1.Key Laboratory of Isotope Geochronology and geochemistry,{2. {2. of geochemistry,Chinese Academy of Sciences,{2. 510640,china 2.Department of Earth Sciences,The University of Hong Kong,Hong Kong 3.State Key of Continental Dynamics,Department of Geology,The Northwest University,Xi''an

＜正＞The majority of the gneissic granites were traditionally thought to be the component of the Precambrian basement in the eastern South china ***-six gneissic granites from the Wugong,northern Wuyi, southern Wuyi and Yunkai Domains gave the zircon U-Pb ages of 42.～456 Ma（n=6）,410～457 Ma（n=5）, 42.～438 Ma（n=8） and 415～450 Ma（n=7）,respectively,being actually the Kwangsian（410～457 Ma） granites. The gneissic granites are strongly peraluminous silica-rich granites with high SiO2.A12.3,low MgO,TiO2.and tFeO *** exhibit strongly negative Ba,Sr,Nb,P and Ti anomalies and positive Pb anomalies,and have

关键词：

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中华猕猴桃果实香气成分的GC-MS分析

分析测试学报 2002年第2期21卷 58-60页

作者：李华涂正顺王华刘芳李可昌西北农林科技大学葡萄酒学院陕西杨陵712100 中国科学院广州地球化学研究所有机分析测试中心广东广州510640

采用溶液萃取法 ,提取“早鲜”猕猴桃果实中的香气成分 ,经气相色谱 -质谱联机分析 ,鉴定出45个香气组分 ,占总峰面积的95.9%;其相对含量 ,以棕榈酸、辛酸、油酸、3_羟基丁酸乙酯、(Z,Z)_9,12.十八二烯酸、1,2.4_三羟基_(对)_萜烷、(E)... 详细信息

采用溶液萃取法 ,提取“早鲜”猕猴桃果实中的香气成分 ,经气相色谱 -质谱联机分析 ,鉴定出45个香气组分 ,占总峰面积的95.9%;其相对含量 ,以棕榈酸、辛酸、油酸、3_羟基丁酸乙酯、(Z,Z)_9,12.十八二烯酸、1,2.4_三羟基_(对)_萜烷、(E)_2.己烯醛、1,2.苯二甲酸双(2.甲氧基乙基)酯、硬脂酸、2.己烯醛等为主。

关键词：猕猴桃果实香气成分气相色谱-质谱法分析 GC-MS 溶剂萃取

反转构造盆地裂缝特征——以松辽盆地大庆三肇地区为例

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石油与天然气地质 2002年第4期23卷 361-363.页

作者：张莉岳乐平杨亚娟王秀娟西北大学地质系大庆勘探开发研究院黑龙江大庆163453

松辽盆地主要经历了伸展构造期和反转构造期。伸展构造期主要形成一组近NS向的拉张破裂裂缝和两组斜交共轭剪裂缝。反转构造期主要形成NE ,NW向两组共轭剪裂缝和一组近EW向的横张裂缝。盆地东部生长断层的活动到青山口组末期才基本结束... 详细信息

松辽盆地主要经历了伸展构造期和反转构造期。伸展构造期主要形成一组近NS向的拉张破裂裂缝和两组斜交共轭剪裂缝。反转构造期主要形成NE ,NW向两组共轭剪裂缝和一组近EW向的横张裂缝。盆地东部生长断层的活动到青山口组末期才基本结束。由于生长断层活动期间泉头组三段、四段尤其是青山组的沉积物基本处于塑性状态 ,因此构造裂缝不发育。伸展期形成的裂缝由于经历了较长时间的成岩作用 ,裂缝多被方解石充填 ,有效程度低。进入反转构造期后 ,盆地内储层已经成岩 ,在挤压作用下形成了构造裂缝。因此。

关键词：反转构造松辽盆地三肇地区裂缝特征油气地质

Mantle contributions to granitoids associated with Sn mineralization:Geochemical and isotopic evidence from the giant Dachang deposit,South china

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Geoscience Frontiers 2024年第1期15卷 187-208页

作者： Tingyi wang Qihai Shu Xiaoping Xia Chao Li Yanning wang Jiahao Chen Xiang Sun M.Santosh Qingfei wang State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China Frontiers Science Center for Deep-time Digital Earth China University of Geosciences(Beijing)Beijing 100083China State Key Laboratory of Isotope geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China National Research Center for Geoanalysis Chinese Academy of Geological SciencesBeijing 100037China Department of Earth Science University of AdelaideAdelaideSouth Australia 5005Australia State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China

Major Sn deposits are commonly linked to crust-derived and highly evolved granites,with magma generation aided by mantle ***,whether and how the mantle components contribute to Sn polymetallic mineralization remains *** this study,in combination with a compilation of equivalent data in the region,we provide new constraints on this issue based on detailed investigations on the petrogenesis and metallogenic significance of granitoids including the causative batholith and later granodiorite porphyry dike in the giant Dachang Sn deposit from South *** former has zircon U-Pb ages of 93-91 Ma and belongs to highly evolved S-type biotite granite,which experienced fractionation of massive *** latter shows zircon U-Pb ages of 90 Ma and displays I-type granite *** batholith was mainly derived from the dehydration melting of biotite in the metasedimentary sources,as revealed by the relatively low whole-rock Pb contents(2.71-17.1)and initial T(ti-zr)of 790℃.Compared with the adjacent crust-derived S-type granites(-2..8--5.1)and I-type granites(-11.0 to-5.2.,the Dachang S-type biotite granites present higher zirconεHf(t)values(-9.1 to-2.1).Furthermore,the low magmatic zirconδ18O values(6.2.)and higher apatite LREE(32.7-4114 ppm)and Sr(1137-1357 ppm)contents than of arc-type basic rocks were *** characteristics jointly hint the contributions of mantle *** higher initial T(ti-zr)(>850℃),whole-rock Mg#(52.to 58),apatiteεNd(t)(-9.2.to-6.5)and zirconεHf(t)(-7.6 to 2.5)values but lower zirconδ18O values(6.33 to 8.30‰)of the later granodiorite porphyry dike than those of the batholith also suggest that mantle material was involved in the generation of the dikes,which is evident by the variational features of zircon and apatite trace *** addition,at the zircon Hf2.00 ppm and Eu/Eu*>0.05,the higher zirconΔFMQ values(mostly from-1.8 to 2.0)and H2. contents(100-1100 ppm)of the Dachang

关键词： Highly evolved S-type biotite granite I-type granodiorite porphyry dike Crust-mantle mixing Mantle contributions Dachang Sn mineralization