METAMORPHISM AND CRUSTAL DISPLACEMENTS: NEW INSIGHTS
نویسندگان
چکیده
منابع مشابه
Pliocene-Quaternary crustal melting in central and northern Tibet and insights into crustal flow
There is considerable controversy over the nature of geophysically recognized low-velocity-high-conductivity zones (LV-HCZs) within the Tibetan crust, and their role in models for the development of the Tibetan Plateau. Here we report petrological and geochemical data on magmas erupted 4.7-0.3 Myr ago in central and northern Tibet, demonstrating that they were generated by partial melting of cr...
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Metamorphism along the southern margin of the Archean Superior Province has been historically attributed to the Penokean orogeny. A narrow corridor of amphibolite facies rocks north of the main suture does record 1.83–1.80 Ga metamorphic monazite U–Th–Pb ages that mark the culmination of arc accretion. However, subsequent widespread amphibolite facies metamorphism and associated magmatism is re...
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Proterozoic rocks of the southwestern United States exhibit a variety of tectonometamorphic histories that can all be explained by a characteristic looping style of pressure-temperature (P-T) path. The path is fundamentally clockwise. However, because the rocks were cooled isobarically at 3 kbar after tectonism, the cooling path crosses the prograde path, leading to a geometry with a counterclo...
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[1] The Cenozoic rift system of Baikal, located in the interior of the largest continental mass on Earth, is thought to represent a potential analog of the early stage of breakup of supercontinents. We present a detailed P wave velocity structure of the crust and sediments beneath the Central Basin, the deepest basin in the Baikal rift system. The structure is characterized by a Moho depth of 3...
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ژورنال
عنوان ژورنال: Episodes
سال: 1979
ISSN: 0705-3797,2586-1298
DOI: 10.18814/epiiugs/1979/v2i3/001