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Geochemistry and spatial distribution of OIB and MORB in A’nyemaqen ophiolite zone: Evidence of Majixue-shan ancient ridge-centered hotspot

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Science China Earth Sciences 2007年第2期50卷 197-208页

作者： GUO AnLin ZHANG GuoWei sun yangui ZHENG JianKang LIU Ye WANG JianQi National Key Lab of Continental Dynamics Northwest UniversityXi’an 710069China Qinghai Institute of Geological Survey Xining 810012China

The mafic volcanic association is made up of OIB, E-MORB and N-MORB in the A'nyemaqen Paleozoic ophiolites. Compared with the same type rocks in the world, the mafic rocks generally display lower Nb/U and Ce/Pb ratios and some have Nb depletion and Pb enrichment. The OIB are LREE-enriched with (La/Yb)N =5―20, N-MORB are LREE-depleted with (La/Yb)N = 0.41―0.5. The OIB are featured by incompatible element enrichment and the N-MORB are obviously depleted with some metasomatic ef- fect, and E-MORB are geochemically intermediated. These rocks are distributed around the Majixue- shan OIB and gabbros in a thickness greater than a thousand meters and transitionally change along the ophiolite extension in a west-east direction, showing a symmetric distribution pattern as centered by the Majixueshan OIB, that is, from N-MORB, OIB and E-MORB association in the Dur'ngoi area to OIB in the Majixueshan area and then to N-MORB, OIB and E-MORB assemblage again in the Buqing- shan area. By consideration of the rock association, the rock spatial distribution and the thickness of the mafic rocks in the Majixueshan, coupled with the metasomatic relationship between the OIB and MORB sources, it can be argued that the Majixueshan probably corresponds to an ancient hotspot or an ocean island formed by mantle plume on the A'nyemaqeh ocean ridge, that is the ridge-centered hotspot, tectonically similar to the present-day Iceland hotspot.

关键词： A’nyemaqen ophiolite zone OIB N-MORB and E-MORB association spatial distribution Majixueshan ridge-centered hotspot me- tasomatism mantle plume

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化隆盆地西南部滑坡群应力控制的机制

水土保持学报 1989年第2期3卷 90-96页

作者：孙延贵青海省区域地质综合调查大队

本文根据1987年在化隆盆地所进行的1∶5万区域地质调查所得的资料,综合分析了该区滑坡的分布规律及其特征,新构造的断裂、节理、褶皱等岩石破裂和弯曲变形的应力场特征,滑坡的发生与新构造应力场的关系等。认为在化隆盆地内部进行农业... 详细信息

本文根据1987年在化隆盆地所进行的1∶5万区域地质调查所得的资料,综合分析了该区滑坡的分布规律及其特征,新构造的断裂、节理、褶皱等岩石破裂和弯曲变形的应力场特征,滑坡的发生与新构造应力场的关系等。认为在化隆盆地内部进行农业、公路和水利水电建设时,不仅要考虑河流侵蚀、边坡条件和有效临空面等滑坡发生的外在条件,还应特别注意北西—南东和北东—南西两个易发生剪切破裂变形的方向。

关键词：化隆盆地滑坡群应力控制滑坡

组合夹具组装计算机辅助设计软件MFS CAD R5.0

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航空标准化与质量 1999年第2期 38-41页

作者：孙言贵保定向阳精密机械厂

介绍了供工装设计部门和组合夹具站使用的ＭＦＳＣＡＤＲ５．０《组合夹具组装计算机辅助设计软件》的功能、特点和运行环境。应用Ｒ５．０软件组装夹具既快速又准确，并能准确无误地统计出整套组合夹具所用元件的名称和数量，生成任意... 详细信息

介绍了供工装设计部门和组合夹具站使用的ＭＦＳＣＡＤＲ５．０《组合夹具组装计算机辅助设计软件》的功能、特点和运行环境。应用Ｒ５．０软件组装夹具既快速又准确，并能准确无误地统计出整套组合夹具所用元件的名称和数量，生成任意视向的立体装配图。

关键词：组合夹具组装设计软件

青海省共和盆地周缘晚古生代镁铁质火山岩Sr-Nd-Pb同位素地球化学及其地质意义

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岩石学报 2007年第4期23卷 747-754页

作者：郭安林张国伟孙延贵程顺有强娟西北大学大陆动力学国家重点实验室西安710069

青海省共和盆地周缘晚古生代镁铁质火山岩分属阿尼玛卿蛇绿混杂带,宗务隆构造带和苦海-赛什塘带。阿尼玛卿带正常洋中脊玄武岩(N-MORB)样品具有较高的^(87)Sr/^(86)Sr(t)比值(0.7066～0.7084)、高的ε_(Nd)(t)(12.2～12.8)和较低的^(206... 详细信息

青海省共和盆地周缘晚古生代镁铁质火山岩分属阿尼玛卿蛇绿混杂带,宗务隆构造带和苦海-赛什塘带。阿尼玛卿带正常洋中脊玄武岩(N-MORB)样品具有较高的^(87)Sr/^(86)Sr(t)比值(0.7066～0.7084)、高的ε_(Nd)(t)(12.2～12.8)和较低的^(206)Pb/^(204)Pb初始值(17.72～17.79)。这些同位素特征类似于秦岭勉略蛇绿岩带的N-MORB以及印度洋低^(206)Pb/^(204)Pb高^(143)Nd/^(144)Nd N-MORB。该带中的洋岛玄武岩(OIB)的^(87)Sr/^(86)Sr比值为0.7036～0.7044,ε_(Nd)(t)=4.4～4.8,^(206)Pb/^(204)Pb=17.45～17.62。其Sr和Nd同位素比值可与印度洋代表热点构造的洋岛玄武岩对比,但^(206)Pb/^(204)Pb低于印度洋的热点构造玄武岩,因此,具有类似印度洋低^(143)Nd/^(144)Nd比值MORB同位素特征。宗务隆构造带的N-MORB的Sr同位素比值在0.7041～0.7058,ε_(Nd)(t)=6.1～8.4,^(206)Pb/^(204)Pb=17.51～17.90,划归高^(143)Nd/^(144)Nd比值的N-MORB。苦海大陆裂谷玄武岩显示了高的^(87)Sr/^(86)Sr同位素比值(0.7115和0.7104)和低的ε_(Nd)(t)值(-1.7和-2.5),其^(206)Pb/^(204)Pb(17.64和17.46)与上述大洋玄武质岩石无显著区别。上述各岩类的同位素特征反映了它们生成的构造环境和陆壳组分混染的程度。阿尼玛卿带的N-MORB代表了典型的来自亏损地幔源区的洋中脊产物。与勉略带同类岩石可能来自同一源区。OIB可能属于热点构造成因的洋岛产物并与MORB一起构成了阿尼玛卿洋洋壳。宗务隆带MORB同样代表了主要源自相对亏损地幔的洋脊产物并指示宗务隆带曾开裂成洋。苦海大陆裂谷玄武岩极高的Sr和低的Nd同位素比值是陆壳物质组分的强烈印记,这与该类火山岩发育在前寒武纪基底之上不无关系。结合本区大洋玄武岩普遍低的Nb/U和Ce/Pb比值,推测它们可能源自EMII与DMM物质的交代混合。按照习惯的想法,明显的Dupal异常(△^(208)Pb/^(204)Pb值=46～103和△^(207)Pb/^(204)Pb值=4～18;大多样品^(87)Sr/^(86)Sr>0.704)指示这些岩石在空间上代表了来自南半球印度洋位置的古洋壳残余。但是,北半球愈来愈多的Dupal异常的发现有可能指示它们是类似现今东南亚多洋岛构造历经"汇聚式(focused)俯冲"的产物。此外,宗务隆带MORB的Dupal异常指示本区古特提斯域的北界较先前所定还要北推200km。

关键词：镁铁质火山岩阿尼玛卿蛇绿混杂带宗务隆构造带苦海-赛什塘带 Sr-Nd-Pb同位素 Dupal异常构造环境

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青藏高原东北缘印支期宗务隆造山带

岩石学报 2009年第1期25卷 1-12页

作者：郭安林张国伟强娟孙延贵李广姚安平西北大学大陆动力学国家重点实验室西安710069 青海省地质调查院西宁810012

位于柴达木地块北缘构造带(柴北缘构造带)与南祁连造山带间的宗务隆构造带发育晚古生代、早中三叠世地层以及石炭纪蛇绿岩地体和具有岛弧性质的二叠纪—早三叠世中酸性火山岩。三个侵入宗务隆带南侧的海西—印支期花岗岩(246Ma天峻南山... 详细信息

位于柴达木地块北缘构造带(柴北缘构造带)与南祁连造山带间的宗务隆构造带发育晚古生代、早中三叠世地层以及石炭纪蛇绿岩地体和具有岛弧性质的二叠纪—早三叠世中酸性火山岩。三个侵入宗务隆带南侧的海西—印支期花岗岩(246Ma天峻南山花岗岩、238Ma青海湖南山花岗岩和215Ma二郎洞花岗岩)分别与俯冲和后碰撞相关。两期明显的构造变形为印支期造山构造和第三纪陆内构造活动印记,前者以300余公里长的韧性剪切带为代表,后者以大规模指向南的逆冲推覆作用为特征。宗务隆构造带经历了由陆内裂陷、洋盆发育和俯冲—碰撞造山的演化过程,既不同于其南侧的柴北缘构造带也不属于北侧的南祁连造山带,而是一在柴北缘和南祁连造山带共同构建的加里东陆块上发育起来的、具有完整板块旋回的印支期造山带。

关键词：宗务隆构造带天峻南山蛇绿岩海西-印支期花岗岩印支期变形宗务隆造山带

青藏高原东北缘多福屯第三纪钠质基性火山岩及构造启示

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地学前缘 2007年第3期14卷 73-83页

作者：郭安林张国伟孙延贵程顺有西北大学大陆动力学国家重点实验室地质系陕西西安710069

位于青藏高原东北缘的多福屯第三纪火山岩，为钠质基性火山岩系。该火山岩（La／Yb）N值在6—11，∑REE平均为117，样品普遍具有不相容元素富集、Pb亏损以及弱的Nb、Ta正异常，Nb／U和Ce／Pb平均值分别为30和17；样品的87^Sr／^86Sr值为... 详细信息

位于青藏高原东北缘的多福屯第三纪火山岩，为钠质基性火山岩系。该火山岩（La／Yb）N值在6—11，∑REE平均为117，样品普遍具有不相容元素富集、Pb亏损以及弱的Nb、Ta正异常，Nb／U和Ce／Pb平均值分别为30和17；样品的87^Sr／^86Sr值为0．7041～O．7069，Nd初始值为0．5129（εNd（t）=6），△^207Pb／^240Pb和△^208Pb／^204Pb分别在11～19和73-84之间，结合高的Sr初始值，表现了特征的Dupal（高放射成因铅）异常。地球化学特征表明，该火山岩属于似OIB性质的陆内火山岩，源区具有DM与EMⅡ混合特点。个别岩石表现出明显陆壳混染的迹象。火山岩源区特征反映了OIB类岩石的复杂性，可能由区域原、古特提斯地幔继承而来，因而是原地的和固有的，并非与青藏高原物质向东挤出有关。通过与邻区同时代火山岩的对比推断，整个高原东北缘新生代火山岩幔源区具有小尺度的不均一性。高原东北缘新生代火山岩的发育可能与较大规模的贺兰-川滇南北复合构造有关。

关键词：青藏高原东北缘多福屯钠质基性火山岩 OIB特征 DM-EMⅡ混合小尺度不均一地幔南北复合构造

柴达木盆地南缘晚奥陶世万宝沟花岗岩：锆石SHRIMP U-Pb年龄、Hf同位素和元素地球化学

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岩石学报 2012年第9期28卷 2950-2962页

作者：王晓霞胡能高王涛孙延贵巨生成青海省地调院卢欣祥李舢齐秋菊中国地质科学院资源研究所国土资源部成矿作用与资源评价重点实验室北京100037 长安大学西安710064 中国地质科学院地质研究所北京100037 青海省地调院西宁810012 河南省地质科学院郑州450053 中国地质大学北京100083

柴达木盆地南缘万宝沟花岗岩体主要由似斑状黑云母石英二长岩、环斑结构黑云母二长花岗岩和中粒黑云母二长花岗岩组成,岩体中发育岩浆暗色包体。环斑结构黑云母二长花岗的锆石SHRIMP U-Pb定年为441±5Ma,表明其形成于晚奥陶世。该花岗岩... 详细信息

柴达木盆地南缘万宝沟花岗岩体主要由似斑状黑云母石英二长岩、环斑结构黑云母二长花岗岩和中粒黑云母二长花岗岩组成,岩体中发育岩浆暗色包体。环斑结构黑云母二长花岗的锆石SHRIMP U-Pb定年为441±5Ma,表明其形成于晚奥陶世。该花岗岩的SiO2含量变化较大(62.20%～75.32%),高钾(3.58%～5.15%)和碱(K2O+Na2O>7%),A/CNK为0.98～1.09,属弱过铝质高钾钙碱性系列;K2O/Na2O(>1)、FeOT/MgO(3.4～6.5)和Ga/Al(2.3～3.1)比值较高,亏损不相容元素Ba、Sr、Nb、P和Ti,相对富集Ta、Hf和Zr,具有A-型花岗岩的特征。黑云母二长花岗岩的εHf(t)=-1.1～10.5,tDM2=744～1490Ma,变化范围较大,表明其物质来源具有多源性,但以壳源为主。较高的εHf(t)(达10)值和较年轻的tDM2(仅为744Ma)暗示,源区中有年轻组分的参与。结合区域地质特征分析,认为该花岗岩形成于后造山的拉张环境。万宝沟花岗岩在结构和地球化学特征上与典型环斑花岗岩有相似之处也有差异,与秦岭中生代环斑结构花岗岩基本相似,表明中央造山带存在古生代和中生代两期环斑结构花岗岩。这将对中央造山带构造演化的进一步研究具有重要的科学意义。

关键词：环斑结构花岗岩 SHRIMP锆石U-Pb年龄地球化学柴达木盆地南缘中央造山带

Age of Yingfeng rapakivi granite pluton on the north flank of Qaidam and its geological significance

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Science China Earth Sciences 2004年第4期47卷 357-365页

作者： XIAO Qinghui1,2, LU Xinxiang1,3, WANG Fei4, sun yangui5, WEI Xiangdong3 & XING Zuoyun6 1. Division of Granite Geology, China Geological Survey, Yichang 443003, China 2. Information Center of Ministry of Land and Resources, Beijing 100812, China 3. Geological Survey of Henan Province and Institute of Geological Research of Henan Province, Zhengzhou 450053, China 4. Geological Institute, China Seismological Bureau, Beijing 100029, China 5. Geological Survey Institute of Qinghai Province, Xining 810032, China 6. China University of Geosciences, Wuhan 430074, China Division of Granite Geology China Geological Survey Yichang China Information Center of Ministry of Land and Resources Beijing China Geological Survey of Henan Province and Institute of Geological Research of Henan Province Zhengzhou China Geological Institute China Seismological Bureau Beijing China Geological Survey Institute of Qinghai Province Xining China China University of Geosciences Wuhan China

The Yingfeng rapakivi granite on the north flank of Qaidam is a newly discovered Proterozoic rapakivi pluton in China, which was found after the discovery of Shachang rapakivi in Miyun County, Beijing and Kuandian rapakivi in Jilin Province. Yingfeng rapakivi pluton is ex-posed on the north side of the suture belt between Qinling-Kunlun orogenic belt and North China plate. U-Pb zircon isotopic dating and Ar-Ar isotopic dating of both hornblende and K-feldspar from the Yingfeng rapakivi granite have been conducted. The results show that the age of (1776±33)Ma at the upper intercept in Concorde diagram represents the age of formation of the plu-ton, whereas the age of (526 281) Ma at the lower intercept and Ar-Ar mineral dating of horn-blende and K-feldspar correspond to the age of a later event affecting the pluton, suggesting that Yingfeng pluton has ever been affected by strong regional Caledonian-Hercynian tectonic movement after its formation. The discovery of middle Proterozoic Yingfeng rapakivi granite pro-vides a petrologic evidence for the timing of cratonization of both the continental crust basement in western China and the basement of the North China plate and for a rifting event taking place in the mid-Proterozoic, suggesting that an amalgamation of ancient China continents had ever happened during the L liang Movement?between the early Proterozoic and the mid-Proterozoic.

关键词： rapakivi, U-Pb dating, Ar-Ar dating, Kunlun-Qinling orogenic belt.

Zircon SHRIMP U-Pb ages and trace element geochemistry of the Kuhai gabbro and the Dur'ngoi diorite in the southern east Kunlun tectonic belt, Qinghai, Western China and their geological implications

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Science China Earth Sciences 2007年第Z2期50卷 331-338页

作者： LI WangYe LI ShuGuang GUO AnLin sun yangui ZHANG GuoWei CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China Department of Geology Northwest University Xi'an 710069 China Remote Sensing Center of Qinghai Institute of Geological Survey Xining 810012 China Department of Geology Northwest University Xi'an 710069 China

Timing of the intermediate-basic igneous rocks developed in the area of Kuhai-A'nyêmaqên along the southern east Kunlun tectonic belt is a controversial issue. This paper presents new zircon SHRIMP U-Pb dating data for igneous zircons from the Kuhai gabbro and the Dur'ngoi diorite in the Kuhai-A'nyemaqen tectonic belt, which are 555±9 Ma and 493±6 Ma, respectively. The trace element geochemical features of the Kuhai gabbro and the Dur'ngoi diorite are similar to those of ocean island basalts (OIB) and island arc basalts (IAB), respectively. Thus, the Kuhai gabbro with the age of 555±9 Ma and OIB geochemical features is similar to the Yushigou oceanic ophiolite in the North Qilian orogen, whereas the Dur'ngoi diorite with the age of 493±6 Ma and IAB geochemical features is similar to the island arc volcanic rocks developed in the north Qaidam. The Late Neoproterozoic to Early Ordovician ophiolite complex in the area of Kuhai-A'nyêmaqên suggests that the southern margin of the "Qilian-Qaidam-Kunlun" archipelagic ocean in this period was located in the southern east Kunlun tectonic belt. Therefore, the southern east Kunlun tectonic belt in the early Paleozoic is not comparable to the Mianlüe tectonic belt in the Qinling orogenic belt.

关键词： Kunlun tectonic belt, zircon SHRIMP U-Pb dating, "Qilian-Qaidam-Kunlun" archipelagic ocean, ophiolite complex