Isotopic evidence for a Precambrian metamorphic event within the Charcot Land window, East
V tj Rb-Sr, U-Pb and K-Ar analyses on rocks and minerals from a tectonic window below a Caledonian thrust f sheet in the westernmost part of the Scoresby Sund region (70°-72°N) give evidence for a Precambrian age of formation. The Charcdt Land supracrustal sequence rests on a basement that is probab...
Main Authors: | , , , |
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Other Authors: | |
Format: | Text |
Language: | English |
Published: |
1980
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Subjects: | |
Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.513.8540 http://2dgf.dk/xpdf/bull29-03-151-160.pdf |
Summary: | V tj Rb-Sr, U-Pb and K-Ar analyses on rocks and minerals from a tectonic window below a Caledonian thrust f sheet in the westernmost part of the Scoresby Sund region (70°-72°N) give evidence for a Precambrian age of formation. The Charcdt Land supracrustal sequence rests on a basement that is probably of Archaean development and older than at least 2100 m.y. The major regional metamorphism of the supracrustal rocks is probably not much older than the intrusion of two post-kinematic bodies, i.e. about 1840 m.y. Low-grade metamorphism in a tillite and low-grade retrogressive overprinting of the supra-crustal rocks are related to Caledonian orogenesis. |
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