کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9536179 1357091 2005 20 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Pull-apart emplacement of the Margeride granitic complex (French Massif Central). Implications for the late evolution of the Variscan orogen
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات زمین شناسی
پیش نمایش صفحه اول مقاله
Pull-apart emplacement of the Margeride granitic complex (French Massif Central). Implications for the late evolution of the Variscan orogen
چکیده انگلیسی
A microstructural, magnetic fabric and gravity study is performed on the Carboniferous Margeride granitic complex that crops out in the central part of the Variscan French Massif Central. This complex consists of three facies, namely, a main porphyritic monzogranite, a two-mica granite, and late leucogranite dykes and stocks. In spite of local variations, the magnetic lineation mainly trends NW-SE with a shallow plunge throughout the complex. The magnetic foliation pattern is more complex with various strikes and generally a moderate dip. This fabric pattern complies with the late-orogenic NW-SE regional extensional deformation already recognised in this part of the Variscan Belt. New gravity measurements complete available data and are used to build up a gravity map and a cross-section with which four gravity minima are identified. Three gravity minima are interpreted as extensional fractures consistent with a NW-SE maximum stretching. The last gravity low corresponds to an extensional jog between the two westernmost fractures. The structural and gravity features of the complex are used to propose a feeding and emplacement model controlled by the regional late-orogenic extensional tectonics. The Margeride complex is interpreted as a kilometre-scale laccolith-like pluton emplaced in a transtensional setting controlled by a NW-SE opening direction. Such a model strengthens the relationships between pluton emplacement and late-orogenic collapse of the Variscan Belt.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Structural Geology - Volume 27, Issue 9, September 2005, Pages 1610-1629
نویسندگان
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