Polyorogenic history of the East Greenland Caledonides
The Caledonian orogen of East Greenland contains remnants of Archean, Paleoproterozoic, late Mesoproterozoic, and early Neoproterozoic rocks that occur within far-traveled thrust sheets, and bear witness to a complex polyorogenic history of the region prior to Caledonian orogenesis. Archean and Pale...
Main Authors: | , , , , , , |
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Format: | Article in Journal/Newspaper |
Language: | unknown |
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Geological Society of America
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Online Access: | http://hdl.handle.net/1885/82557 https://openresearch-repository.anu.edu.au/bitstream/1885/82557/5/Nutman_2008_polyorogenic_Caledonides.pdf.jpg https://openresearch-repository.anu.edu.au/bitstream/1885/82557/7/01_Kalsbeek_Polyorogenic_history_of_the_2008.pdf.jpg |
Summary: | The Caledonian orogen of East Greenland contains remnants of Archean, Paleoproterozoic, late Mesoproterozoic, and early Neoproterozoic rocks that occur within far-traveled thrust sheets, and bear witness to a complex polyorogenic history of the region prior to Caledonian orogenesis. Archean and Paleoproterozoic complexes consist mainly of granitoid orthogneisses. A succession of Paleoproterozoic tholeiitic metabasalts is present in some of the foreland windows. A major unit of late Mesoprotero zoic metasedimentary rocks (Krummedal supracrustal sequence) contains early Neoproterozoic (ca. 950 Ma) as well as Caledonian granites. There is evidence for Archean (ca. 2800-2600 Ma), Paleoproterozoic (2000-1750 Ma), and late Grenvillian (ca. 950 Ma) deformation and metamorphism, but Caledonian overprinting complicates the study of these events. This paper presents a broad overview of the various rock units with structural, geochemical, and geochronologic data. The Paleoproterozoic metabasaltic rocks from the foreland windows are described in more detail. |
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