检索结果-南通市图书馆

Metamorphic Evolution of garnet amphibolite from the Yaganbuyang Area in the South Altyn Orogen,West China:Insights from Phase Equilibria Modeling and Geochronology

引用

Journal of Earth Science 2023年第3期34卷 640-657页

作者： Xin Li Liang Liu Xiaoying Liao Yongsheng Gai Tuo Ma Guojian Geng Tong Li State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an 710069China

garnet amphibolite is one of the common metabasic rocks exposed in collisional orogenic belt,the metamorphic evolution of which is associated closely with orogenic *** Yaganbuyang garnet amphibolites occur as blocks hosted by massive granitic gneiss,and consist mainly of hornblende,garnet,clinopyroxene,plagioclase,biotite,quartz with minor rutile/ilmenite and phengitic *** garnet amphibolites were interpreted to have experienced decompression-dominated evolution that can be divided into three generations(M1,M2,M3),based on the petrographic observations and phase equilibria modeling calculated by *** assemblage of the first generation(M1)is inferred to possibly be dominated by garnet+omphacite+rutile+phengite+quartz,which is modeled to be roughly stable at P>25 kbar and T>800℃.The second generation(M2)is characterized by the local symplectites of clinopyroxene+plagioclase produced from omphacite,indicating a near-isothermal decompression from~23.8 kbar/875℃to~10 kbar/852℃.The third generation(M3)is marked by the kelyphitic rims of plagioclase+hornblende around garnet and of hornblende+ilmenite around clinopyroxene,involving the late-stage retrogression from~9.8 kbar/848℃to~5.8 kbar/645℃.Zircon U-Pb dating yielded one group metamorphic age of c.500 Ma that is interpreted to represent the timing of the peak eclogite-facies metamorphism.A combination of petrography observation,phase modeling results and geochronology data suggests that the Yaganbuyang garnet amphibolites have once undergone eclogite-facies metamorphism by continental subduction rather than crustal ***,the Yaganbuyang area is an eastward extension part of the South Altyn HP-UHP metamorphic belt.

关键词： South Altyn Orogen garnet amphibolite phase equilibria modeling zircon U-Pb dating geochronology

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

Metamorphism and geochronology of garnet amphibolite from the Beishan Orogen,southern Central Asian Orogenic Belt:Constraints from P-T path and zircon U-Pb dating

引用

Geoscience Frontiers 2020年第4期11卷 1189-1201页

作者： Wenbin Kang Wei Li Lei Kang Yunpeng Dong Dazhi Jiang Jiwei Liang Haoqiang Dong State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China Key Laboratory for the Study of Focused Magmatism and Giant Ore Deposits of Ministry of Natural Resources Xi'an Center of China Geological SurveyCGSXi'an 710054ShaanxiChina Department of Earth Sciences Western UniversityLondonOntarioN6A 5B7Canada School of Earth Science&Resources Chang’an UniversityXi’an 710054China

Numerous lenses of garnet amphibolite occur in the garnet-bearing biotite-plagioclase gneiss belt in the Baishan area of the Beishan Orogen,which connects the Tianshan Orogen to the west and the Mongolia-Xing’anling Orogen to the *** study of metamorphism in Beishan area is of great significance to explain the tectonic evolution of Beishan *** to the microstructures,mineral relationships,and geothermobarometry,we identified four stages of mineral assemblages from the garnet amphibolite sample:(1) a pre-peak stage,which is recorded by the cores of garnet together with core-inclusions of plagioclase(Pl1);(2) a peak stage,which is recorded by the mantles of garnet together with mantle-inclusions of plagioclase(Pl2)+amphibole(Amp1)+Ilmenite(Ilm1)+biotite(Bt1),developed at temperature-pressure(P-T) conditions of 818.9-836.5℃ and7.3-9.2 kbar;(3) a retrograde stage,which is recorded by garnet rims + plagioclase(Pl3)+amphibole(Amp2)+orthopyroxene(Opx1)+biotite(Bt2)+Ilmenite(Ilm2),developed at P-T conditions of 796.1-836.9℃ and5.6-7.5 kbar;(4) a symplectitic stage,which is recorded by plagioclase(Pl4)+orthopyroxene(Opx2)+amphibole(Amp3)+biotite(Bt3) symplectites,developed at P-T conditions of 732 ±59.6℃ and 6.1 ±0.6 ***,the U-Pb dating of the Beishan garnet amphibolite indicates an age of 301.9 ±4.7 Ma for the protolith and 281.4±8.5 Ma for the peak metamorphic ***,the mineral assemblage,P-T conditions,and zircon U-Pb ages of the Beishan garnet amphibolite define a near-isothermal decompression of a clockwise P-T-t(Pressure-Temperature-time) path,indicating the presence of over thickened continental crust in the Huaniushan arc until the Early Permian,then the southern Beishan area underwent a process of thinning of the continental crust.

关键词： Beishan orogen garnet amphibolite P-T-t path Zircon U-Pb dating

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 of garnet amphibolites from the Hualong Group: Implications for Metamorphic Evolution of the Qilian Orogen, NW China

引用

Journal of Earth Science 2018年第5期29卷 1102-1115页

作者： Yilong Li Limin Zhao Zhuoyang Li Biji Luo Jianping Zheng Fraukje M.Brouwer School of Earth Sciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Geology & Geochemistry Group Department of Earth Sciences VU Amsterdam

The Qilian Orogen marks the junction of the North China, South China and Tarim cratons. The mechanism of continental growth during the formation of the orogen remains unclear. Based on detailed fieldwork, we present a systematic study of petrography, mineral chemistry and phase equilibria of garnet amphibolites from the Hualong Group, which represents the Precambrian basement in the southern accretionary belt of the Qilian Orogen. The garnet amphibolites mainly consist of amphibole, plagioclase, garnet and quartz, with minor pyroxene, biotite and ilmenite. A peak stage of upper amphibolite facies to low-temperature granulite facies metamorphism and retrograde metamorphism in the amphibolite facies affected the samples. garnet has a homogeneous composition of Alm66-71Grs14-17Prp9_12Sps3-s, amphibole is ferro-hornblende, biotite belongs to the ferro-biotite species and pyroxene is dominated by orthopyroxene with few clinopyroxene. Pseudosection modeling of the garnet amphibolite samples indicates clockwise P-T paths. The samples witness peak metamorphism at conditions of -4.9-6.3 kbar and -755-820 ℃ in the upper amphibolite facies to low- temperature granulite facies, and retrograde cooling and decompression at conditions of-2.5-3.1 kbar and -325-545 ℃. It is inferred that peak metamorphism with high temperature and low pressure occurred at ca. 450 Ma during northward subduction of the South Qilian oceanic crust beneath the central Qilian Block. When continental collision occurred between the central Qilian and the Qaidam blocks, the Hualong Block was aecreted onto the South Qilian accretionary complex and experienced amphibolite facies retrograde metamorphism at ca. 440 Ma.

关键词： Qilian Orogen Hualong Group garnet amphibolite petrology metamorphic P-T path PerpleX.

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

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

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：