检索结果-南通市图书馆

The role of structural inheritance in continental break-up and exhumation of alpine Tethyan mantle(Canavese Zone,Western Alps)

引用

Geoscience Frontiers 2020年第1期11卷 167-188页

作者： Andrea Festa Gianni Balestro Alessandro Borghi Sara De Caroli Andrea Succo Dipartimento di Scienze della Terra Universitàdi TorinoTorinoItaly Dipartimento di Scienze Chimiche della Vita e della SostenibilitàAmbientaleUniversitàdi ParmaParmaItaly

The Canavese Zone(CZ)in the Western Alps represents the remnant of the distal passive margin of the Adria microplate,which was stretched and thinned during the Jurassic opening of the alpine *** detailed geological mapping,stratigraphic and structural analyses,we document that the continental break-up of Pangea and tectonic dismemberment of the Adria distal margin,up to mantle rocks exhumation and oceanization,did not simply result from the syn-rift Jurassic extension but was strongly favored by older structu ral inheritances(the Proto-Canavese Shear Zone),which controlled earlier lithospheric *** findings allowed to redefine in detail(i)the tectono-stratigraphic setting of the Variscan metamorphic basement and the Late Carbonife rous to Early Cretaceous CZ succession,(ii)the role played by inherited Late Carboniferous to Early Triassic structures and(iii)the significance of the CZ in the geodynamic evolution of the alpine *** large amount of extensional displacement and crustal thinning occurred during different pulses of Late Carbonife rous-Early Triassic strike-slip tectonics is wellconsistent with the role played by long-lived regional-scale wrench faults(e.g.,the East-Variscan Shear Zone),suggesting a re-discussion of models of mantle exhumation driven by low-angle detachment faults as unique efficient mechanism in stretching and thinning continental crust.

关键词： alpine tethys Western Alps Jurassic ophiolite Structural inheritance Continental break-up Mantle exhumation

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

New isotopic constraints on age and magma genesis of an embryonic oceanic crust:The Chenaillet Ophiolite in the Western Alps

New isotopic constraints on age and magma genesis of an embr...

引用

中国科学院地质与地球物理研究所2013年度（第13届）学术年会

作者： Xian-Hua Li Michel Faure Wei Lin Gianreto Manatschal State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences Institut des Sciences de la Terre d'Orleans CNRS-Universite d'Orteans Institut de Physique du Globe de Strasbourg CNRS UMR7516Universite de Strasbourg

The Chenaillet Ophiolite is one of the best-preserved remnants of the Piemont-Liguria oceanic basin,a branch of the Central Atlantic that opened during the separation of Adria/Africa from *** numerous studies of structure,petrology,geochemistry and isotope geochronology,the timing and genesis of various magmatic rocks within the Chenaillet Ophiolite are still *** provide in this study integrated in situ analyses of zircon U-Pb age and O-Hf isotopes for the troctolite and albitite within the Chenaillet *** new results indicate that the troctolite and albitite crystallized synchronously at-165 *** from the troctolite have homogeneous Hf and 0 isotopic compositions,withεHf(T) = +13.5±1.0(2SD) andδO = 5.4±0.4‰(2SD),indicating crystallization from magmas that were derived from a depleted,MORB-like *** albitite zircons give consistent ***(T) values(+13.0 to +13.5) within errors with those of troctolite zircons,but variableδO *** altered zircon domains have relatively lowδO values of 4.7±0.6‰(2SD) due to subsolidus hydrothermal alteration,whilst the least-altered zircon domains giveδO values of 5.1±0.4‰(2SD),indistinguishable within errors with the troctolite zircons and the igneous zircons from the Mid-Atlantic and Southwest Indian Ridges gabbros,norites,and plagiogranites of modern oceanic *** situ zircon O-Hf isotopic data suggest that the troctolites and albitites are most likely cogenetic,with the albitites being formed by extreme fractional crystallization from the basaltic magma. Based on our new age results and compilation of the reliable literature U-Pb age data,the ophiolitic gabbros from Eastern,Central and,Western Alps,Liguria and Corsica crystallized nearly synchronously at 158-166 Ma, suggesting a short life span of < 11 *** the formation of the Piemont-Liguria oceanic domain,rather than a -30 *** span as previously *** Chenaillet ophiolite is likely a remnant of embryonic oceanic cr

关键词： Zircon U-Pb age Zircon O-Hf isotopes Plagiogranites Chenaillet ophiolite alpine tethys Piemont-Liguria oceanic basin

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Age of alpine Corsica ophiolites revisited:Insights from in situ zircon U–Pb age and O–Hf isotopes

Age of Alpine Corsica ophiolites revisited:Insights from in ...

引用

中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： Xian-Hua Li Michel Faure Philippe Rossi Wei Lin Didier Lahondère State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences Institut des Sciences de la Terre d’Orléans Université d’Orléans

Knowledge of the age and timing of ophiolite sequences is essential for understanding the mechanisms of plate *** ophiolites in the Schistes Lustres and the Upper nappes of alpine Corsica represent remnants of the Liguria-Piemonte ocean basin that formed as a branch of the Central Atlantic basin during the opening of the Mesozoic Western alpine *** numerous isotopic and paleontological studies,the age and timing of the ophiolites in the Schistes Lustres nappe are still *** study presents integrated in situ analyses of zircon U-Pb age and O-Hf isotopic data for ophiolitic gabbros and plagiogranites from three localities in the Schistes Lustres nappe of Eastern *** new results demonstrate that these rocks crystallized synchronously at-159 Ma,approximately 10 *** than the ophiolites in the Balagne Upper *** from the gabbros and plagiogranites are characterized by highly positiveεHf(t)(+15.0 to+15.9)and mantlelikeδO(5.2-5.4‰)***,these ophiolitic rocks were cogenetic,and crystallized from magmas produced by partial melting of a depleted,N-MORB type *** contrast,in the Balagne Upper nappe,the-169 Ma ophiolites contain numerous xenocrystic zircons inherited from a continental *** current knowledge of isotopic geochronology and geochemistry supports a paleogeographic reconstruction,in which the earliest ophiolites in the Balagne nappe were emplaced close to a continental margin at-169 Ma,while the N-MORB type ophiolites in the Schistes Lustres nappe were likely formed approximately 10 *** in the central part of the Liguria-Piemonte oceanic *** relative location of the Schistes Lustres and Balagne Upper nappes with respect to continental margins is discussed.

关键词： Zircon U–Pb age Zircon O–Hf isotopes Ophiolite Corsica alpine tethys Liguria–Piemonte oceanic basin

来源： cnki会议评论

在线全文

cnki会议

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：