检索结果-南通市图书馆

Petrology, Geochemistry and Tectonic Significance of the Metamorphic Peridotites from Longmuco-Shuanghu Ophiolitic Melange belt, Tibet

引用

Acta Geologica Sinica(English Edition) 2013年第2期87卷 426-439页

作者： WU Yanwang LI Cai XIE Chaoming WANG Ming hu peiyuan College of Earth Science Jilin University

Taoxinghu metamorphic peridotite is a firstly reported mantle sequence of ophiolite since Longmuco-Shuanghu-Lancangjiang suture zone （LSLSZ） was proposed, and it is also an important discovered for ophiolite studying in central Qiangtang. Based on detailed analyses of whole-rock geochemistry of Taoxinghu metamorphic peridotites and contrast to metamorphic peridotites in typical ophiolites worldwide, the paper investigates their petrogenesis and geological implication. The petrologic results show that the protolith of Taoxinghu metamorphic perdotites have the mineral assemblage and texture characteristic of mantle peridotite. Most metamorphic peridotites hav near global abyssal peridotites major elements contents, while the few is similar to SSZ-type peridotites. They exhibit typically U-shaped REE patterns, characterized by slight enrichment of LREE and HREE relative to MREE and a low fractionated LREE to HREE segment. Trace elements contents are low and all samples are strong enrichment in Cs, U, Pb, weak enrichment in Ba and depletion in Th, but negative Nb anomalies are only observed in few samples. That suggests Taoxinghu metamorphic peridotites have depletion mantle and suprasubduction affinities. A two-stage evolution history is considered： Taoxinghu metamorphic peridotites originated as the residue from melting at a ridge with 7%-20% degree of fraction melting and were subsequently modified by interaction with mafic melt and aqueous fluid within mantle wedge on subducted zone. Combined with previous studies, we preliminarily propose Taoxinghu metamorphic peridotites may be the Products of initial rifting of palo-Tethys, forming at middle Ordivician-upper Cambrian, and they may be the direct evidences for spreading of palo-Tethys.

关键词： geochemistry metamorphic peridotite Taoxinghu Longmuco-Shuanghu suturezone Tibetan plateau

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Petrology, geochemistry and geochronology of the Zhongcang ophiolite, northern Tibet: implications for the evolution of the Bangong-Nujiang Ocean

引用

Geoscience Frontiers 2018年第5期9卷 1369-1381页

作者： Yue Tang Qingguo Zhai peiyuan hu Xuchang Xiao Haitao Wang Institute of Geology Chinese Academy of Geological Sciences

Ophiolites are widespread along the Bangong-Nujiang suture zone, northern Tibet. However, it is still debated on the formation ages and tectonic evolution process of these ophiolites. The Zhongcang ophiolite is a typical ophiolite in the western part of the Bangong-Nujiang suture zone. It is composed of serpentinized peridotite, cumulate and isotropic gabbros, massive and pillow basalts, basaltic volcanic breccia, and minor red chert. Zircon SHRIMP Ue Pb dating for the isotropic gabbro yielded weighted mean age of 163.4 ± 1.8 Ma. Positive zircon ε Hf(t) values(+15.0 to +20.2) and mantle-like σ^(18)O values(5.29 ±0.21)% indicate that the isotropic gabbros were derived from a long-term depleted mantle source. The isotropic gabbros have normal mid-ocean ridge basalt(N-MORB) like immobile element patterns with high Mg O, low TiO_2 and moderate rare earth element(REE) abundances, and negative Nb,Ti, Zr and Hf anomalies. Basalts show typical oceanic island basalt(OIB) geochemical features, and they are similar to those of OIB-type rocks of the Early Cretaceous Zhongcang oceanic plateau within the Bangong-Nujiang Ocean. Together with these data, we suggest that the Zhongcang ophiolite was probably formed by the subduction of the Bangong-Nujiang Ocean during the Middle Jurassic. The subduction of the Bangong-Nujiang Tethyan Ocean could begin in the Earlye Middle Jurassic and continue to the Early Cretaceous, and finally continental collision between the Lhasa and Qiangtang terranes at the west Bangong-Nujiang suture zone probably has taken place later than the Early Cretaceous(ca. 110 Ma).

关键词： Tibetan plateau Bangong-Nujiang suture zone Ophiolite Geochronology Geochemistry Subduction

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

^(40)Ar/^(39)Ar Thermochronology Constraints on Jurassic Tectonothermal Event of Nyainrong Microcontinent

引用

Journal of Earth Science 2014年第1期25卷 98-108页

作者： Chaoming Xie Cai Li Yanwang Wu Ming Wang peiyuan hu College of Earth Science Jilin University

To reveal the Jurassic tectonothermal event occurring to the Nyainrong microcontinent which is gripped among the Bangong-Nujiang suture zone,^40Ar/^39Ar dating was carried out on the basement orthogneiss and Jurassic granitc gneiss in the microcontinent. In the heating stage, four sam- pies exhibited a flat plateau age, with the value Tp concentrated in the range of 166-176 Ma; isochron age Ti was concentrated in the range of 165-175 Ma, and their corresponding ages were the consistent within allowable range. The ages should be representative of the era of the final deformation of the Amdo gneiss and cooling emplacement of the magmatic rock in the Jurassic. The geochronological studies have shown that the final deformation of microcontinent crystalline basement and the cooling of the Mesozoic large-scale tectonothermal events occurred in late Middle Jurassic. In Middle Jurassic, Nyainrong microcontinent experienced strong tectonic movement. Combining with the geochronologi- cal with isotope geochemistry for the microcontinent, the cause of the tectonothermal event should be attributed to the collision between the Nyainrong microcontinent and South Qiangtang Block following the northward subduction of Bangong-Nujiang oceanic crust.

关键词： Tibet Plateau Nyainrong microcontinent Jurassic tectonothermal event, ^40Ar/^39Ar thermochronology.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Late Cambrian to Early Silurian Granitic Rocks of the Gemuri Area, Central Qiangtang, North Tibet: New Constraints on the Tectonic Evolution of the Northern Margin of Gondwana

引用

Acta Geologica Sinica(English Edition) 2020年第4期94卷 1007-1019页

作者： WANG Haitao ZHAI Qingguo hu peiyuan ZENG Lingsen TANG Yue Zhu Zhicai Key Laboratory of Deep–Earth Dynamaics of the Ministry of Nature Resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China

The Paleozoic tectonic framework and paleo–plate configuration of the northern margin of Gondwana remain controversial. The South Qiangtang terrane is located along the northern margin of Gondwana and records key processes in the formation and evolution of this supercontinent. Here, we present new field, petrological, zircon U-Pb geochronological, and Lu-Hf isotopic data for granitic rocks of the Gemuri pluton, all of which provide new insights into the evolution of the northern margin of Gondwana. Zircon U-Pb dating of the Gemuri pluton yielded three concordant ages of 488.5 ± 2.1, 479.9 ± 8.9, and 438.5 ± 3.5 Ma. Combining these ages with the results of previous research indicates that the South Qiangtang terrane records two magmatic episodes at 502–471 and 453–439 Ma. These two episodes are associated with enriched zircon Hf isotopic compositions(εHf(t) =-10.1 to-3.9 and-16.6 to-6.5, respectively), suggesting the granites were formed by the partial melting of Paleoproterozoic–Mesoproterozoic metasedimentary rocks(Two–stage Hf model ages(TCDM) = 2094–1704 and 2466–1827 Ma, respectively). Combining these data with the presence of linearly distributed, contemporaneous Paleozoic igneous rocks along the northern margin of Gondwana, we suggest that all of these rocks were formed in an active continental margin setting. This manifests that the two magmatic episodes within the Gemuri area were associated with southward subduction in the Proto-(Paleo-) Tethys Ocean.

关键词： granitic rocks Early Paleozoic South Qiangtang Tibet Gondwana

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Late Cretaceous High-Sr/Y Granitic Rocks in the Eastern Tibetan Plateau: Crustal Thickening During Continental Collision

引用

Acta Geologica Sinica(English Edition) 2020年第S01期94卷 19-20页

作者： hu peiyuan ZHAI Qingguo WANG Jun Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China

High-Sr/Y granitic rocks,characterized by intermediate–high SiO2 contents(>56 wt.%),high La/Yb ratios(>20),and low Y(<18 ppm)and Yb(<1.9 ppm)contents,have drawn much attention from geologists in the past *** were originally named adakites and defined as granitic magma in convergent plate margins formed by partial melting of subducted young(<25 Ma),hot,and hydrated oceanic *** studies suggest that these rocks can also be formed in a variety of non-subduction-related tectonic settings through different petrogenetic processes including partial melting of thickened lower continental crust,providing important constraints on crustal growth and evolution throughout the Earth’s *** Tibetan plateau,generally considered as an archetype of collisional orogen,was formed by the successive accretion of different tectonic terranes to the southern margin of the Eurasia plates since the Early ***,the Tibetan plateau comprises several W–E trending terranes(the Kunlun,North Qiangtang,South Qiangtang,and Lhasa terranes)and northernmost India(the Himalaya region).These terranes have undergone significant crustal thickening during the continental collision *** crustal thickness of the Tibetan plateau is asymmetric,being thickest under the Lhasa terrane and thinning more gradually towards the north than to the *** south to north,the crustal thickness increases from^50 km in the Himalaya region,to^70–80 km under the Lhasa terrane,and decreases to^65 km under the North and South Qiangtang terranes and^55 km beneath the Kunlun *** present crustal thickness of the Tibetan plateau has generally been attributed to the Cenozoic collision between the Indian and Eurasian plates and the subsequent intracontinental convergences since^55 ***,doubts were raised about this interpretion in the past few *** example,recent studies indicated the crust of the Lhasa terrane had been significantly thickened during ca.140–130 Ma in

关键词： Tibetan plateau south Qiangtang terrane high-Sr/Y granitic rocks petrogenesis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Pre-Cryogenian integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

引用

Science China Earth Sciences 2024年第4期67卷 899-918页

作者： peiyuan hu Qingguo ZHAI Guochun ZHAO Peter A.CAWOOD Yue TANG Yiming LIU Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Department of Earth Sciences University of Hong KongPokfulam RoadHong Kong 999077China State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China School of Earth Atmosphere&EnvironmentMonash UniversityMelbourneVIC 3800Australia

The composition and geological evolution of pre-Cryogenian material in the Tibetan Plateau and its surrounding areas have played an important role in studying the formation and evolution of early supercontinents on *** paper systematically summarizes the characteristics of pre-Cryogenian sedimentation,paleontology,magmatism,and metamorphism in the Tibetan Plateau and its surrounding *** on existing data,the records of pre-Cryogenian sedimentation and paleontology are mainly concentrated in the Meso-Neoproterozoic,with relatively few records from the Paleoproterozoic or *** oldest geological record is the Hadean detrital zircons in the metamorphosed sedimentary rocks of the Himalaya and Qamdo areas(ca.4.0 Ga).The Tibetan Plateau and surrounding areas preserve records related to the formation and evolution of the Kenor supercraton,and the Columbia,Rodinia,and Gondwana ***-Cryogenian basements can be divided into three types:Tarim-,Yangtze-,and *** Tarim-type basement has a paleogeographic affinity with the northern margins of the Australian and Indian continents and lacks detrital zircon age peaks and magmatic-metamorphic records related to the Rodinia assembly(ca.1.3-0.9 Ga).The Yangtze-type basement records volcanic activity related to global cooling in the latest pre-Cryogenian period and contains Meso-Neoproterozoic stromatolite and micropaleoflora fossils,as well as magmaticmetamorphic records related to Rodinia assembly(ca.1.1-1.0 Ga).The Lhasa-type basement is characterized by Neoproterozoic rift-related sediment records(ca.900 Ma)and high-pressure metamorphic events(ca.650 Ma),with a prominent peak of detrital zircon ages of ca.1.2-1.1 *** is likely to have a paleogeographic affinity with the African continent.

关键词： Tibetan Plateau Pre-Cryogenian Sedimentation Fossils Paleogeographic evolution

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Petrology, Geochemistry and Geochronology of Gabbros from the Zhongcang Ophiolitic Mélange, Central Tibet: Implications for an Intra-Oceanic Subduction Zone within the Neo-Tethys Ocean

引用

Journal of Earth Science 2014年第2期25卷 224-240页

作者： Mengjing Xu Cai Li Wei Xu Chaoming Xie peiyuan hu Ming Wang College of Earth Science Jilin University

In order to investigate the evolution of Shiquanhe-Yongzhu-Jiali ophiolitic melange belt, the gabbros from new discovered Zhongcang ophiolitic melange are studied through petrology, whole-rock geochemistry, zircon U-Pb dating and Lu-Hf isotope. The gabbros investigated in this paper contain cumulate gabbro and gabbro dike, and they have undergone greenschist-amphibolite facies metamorphism. The chondrite normalized rare earth element （REE） patterns of most of these rocks show flat types with slightly light REE （LREE） depletion and the N-MORB normalized incompatible elements diagrams indicate depletion in high field strength elements （HFSE）（Nb, Ta） and enrichment in large ion lithophile elements （LILE）. These gabbros have island arc and mid-ocean ridge basalt af- finities, suggesting that they were originated in an oceanic back arc basin. Whole rock geochemistry and high positive εNd（t） values show that these gabbros were derived from -30% partial melting of a spinel lherzolite mantle, which was enriched by interaction with slab-derived fluids and melts from sediment. U-Pb analyses of zircons from cumulate gabbro yield a weighted mean age of 114.3±1.4 Ma. Based on our data and previous studies, we propose that an intra-oceanic subduction system and back arc basin operated in the Neo-Tethy Ocean of central Tibet during Middle Jurassic and Early Creta- ceous, resembling modern active intra-oceanic subduction systems in the western Pacific.

关键词： Tibet Zhongcang ophiolitic melange gabbro Shiquanhe-Yongzhu-Jiali ophiolitic me- lange belt geochemistry.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Opening of the Longmu Co–Shuanghu–Lancangjiang ocean:constraints from plagiogranites

引用

Chinese Science Bulletin 2014年第20期59卷 3188-3199页

作者： peiyuan hu Cai Li Yanwang Wu Chaoming Xie Ming Wang Jiao Li College of Earth Science Jilin University Institute of Geology and Geophysics Chinese Academy of Sciences

This paper reports new zircon U-Pb ages,and Hf isotope and whole-rock major and trace element data for Cambrian plagiogranites from the Tuobeiling ophiolite in central Qiangtang,Tibetan *** SIMS and LAICP-MS U-Pb dating of the plagiogranites yield weighted mean ages of 504.8±4.2 and 491.6±1.5 Ma,*** zircons from plagiogranites exhibit positive eHf(t)values(ranging from 11.46 to 15.16),indicating that the plagiogranites are derived from depleted *** plagiogranites are characterized by high SiO2and Na2O,low K2O,low REE contents,and flat REE distribution *** rocks have geochemical compositions typical of oceanic plagiogranite and,considered along with their petrography and field relationships,are interpreted to have derived from anatexis of hydrated amphibolites by ductile shearing during transports of the oceanic *** formation age of such type of plagiogranite is slightly younger than that of the associated section of oceanic *** the new results from these plagiogranites suggest that the Longmu Co–Shuanghu–Lancangjiang ocean had probably opened before the Middle Cambrian.

关键词：斜长花岗岩澜沧江锆石U-Pb年龄双湖 ICP-MS Hf同位素羌塘中部微量元素

来源：

维普期刊数据库

同方期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The Ren Co MOR-type Ophiolite in the North-central Tibetan Plateau: A Fast-spreading Ridge Segment of the Meso-Tethys Ocean?

引用

Acta Geologica Sinica(English Edition) 2020年第S01期94卷 57-57页

作者： TANG Yue ZHAI Qingguo hu peiyuan XIAO Xuchang Key Laboratory of Deep-Earth Dynamics of the Ministry of Natural Resources Institute of GeologyChinese Academy of Geological SciencesBeijingChina 100037

The Meso-Tethys Ocean is generally considered to have opened in the late Early Permian as a result of the Cimmerian continental block drifting away from the Gondwana supercontinent. This ocean is also termed the north branch of the Neo-Tethys Ocean, and is now represented by the Bangong–Nujiang suture zone in the north-central Tibetan plateau. However, it is still unknown for the evolutionary history for as such a huge ancient ocean basin. Ophiolites are remnants of oceanic lithosphere and preserve key information in rebuilding the evolutionary history of ancient oceans. In this study, we undertook detailed geological mapping for the Ren Co ophiolite in the middle part of the Bangong–Nujiang suture zone, and a typical Penrose-type ophiolite sequences was newly documented in the Ren Co area. The Ren Co ophiolite comprises serpentinized peridotite, cumulate rock, gabbro/diabase, sheeted dike, massive and pillow lavas, and minor red chert. These rocks exhibit well-preserved mantle and crust rock suites, and show close similarities to oceanic lithospheres at modern fast-spreading ridges. Zircon U–Pb dating for gabbro and plagiogranite yielded ages of 169–147 Ma, which suggest that the Ren Co ophiolites were formed during the Middle to Late Jurassic. Harzburgite in the Ren Co area shows similar features to those of abyssal peridotite indicating the residues of the oceanic mantle. Mafic rocks(basalt, diabase and gabbro) of the Ren Co ophiolite show geochemical features similar to those of typical N-MORB. Moreover, all samples have positive whole-rock εNd(t), and zircon εHf(t) and mantle-like δ18O values. These features suggest that these rocks were derived from a depleted mantle source, thus the Ren Co ophiolite was typical MOR-type ophiolite. We suggest that the Ren Co ophiolite was formed in a fast-spreading mid-ocean-ridge(MOR) setting, and they most likely represented the ridge segment of the BangongNujiang Meso-Tethys Ocean. The Bangong–Nujiang MesoTethys Ocean was a

关键词： Meso-Tethys Ocean Bangong–Nujiang suture zone MOR-type ophiolite mid-ocean-ridge segment

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

不同狭缝尺寸对正丁醇火焰传播及表面流动影响规律研究

引用

工程热物理学报 2022年第6期43卷 1696-1701页

作者：李满厚胡培源王昌建合肥工业大学土木与水利工程学院合肥230009 安徽省氢安全国际联合研究中心合肥230009

本文根据实际火灾场景设计并进行了不同尺寸的大理石狭缝正丁醇火蔓延阻隔实验,测量了火蔓延在狭缝内蔓延时间和温度分布,并定量计算了狭缝内的表面流总热量和狭缝侧壁面热损失。研究发现,火焰在狭缝中表现为“跳跃–回缩–跳跃”脉动... 详细信息

本文根据实际火灾场景设计并进行了不同尺寸的大理石狭缝正丁醇火蔓延阻隔实验,测量了火蔓延在狭缝内蔓延时间和温度分布,并定量计算了狭缝内的表面流总热量和狭缝侧壁面热损失。研究发现,火焰在狭缝中表现为“跳跃–回缩–跳跃”脉动方式蔓延;在狭缝的冷壁效应和黏性力的耦合作用下,狭缝抑制甚至阻隔了火焰蔓延;狭缝火蔓延时间与狭缝长度成正比,与狭缝宽度成反比;当狭缝侧壁热损失占表面热流总热流的比例超过43.3%时,火蔓延被完全抑制,火焰无法穿过狭缝。

关键词：火蔓延正丁醇燃料狭缝结构阻隔时间传热计算

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：