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2 Datasets
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Content:
K-Ar ages of 82 slate and schist (white-mica-rich whole rock) samples are reported for Late Precambrian-Early Ordovician metamorphic rocks of the Wilson, Bowers and Robertson Bay terranes of northern Victoria Land. These are amalgamated in two vertical sections along composite NE-SW horizontal profiles across (1) Oates Coast in the north, and (2) Terra Nova Bay area in the south. The ages are in the range 328-517 Ma. Both profiles show some age variation with altitude, but more importantly, they define an inverted wedge shaped pattern, reflecting a "pop-up" strucure. This is oriented NW-SE at the eastern margin of the Wilson terrane, and the edges coincide with the Exiles and Wilson Thrusts which cross the region. Ages inside the "pop-up" structure are younger, ca. 460-480 Ma, than those along its eastern and western flanks, ca. 490-520 Ma. The K-Ar age patterns thus demonstrate a late Ross Orogenic age (ca. 460 Ma) for this structure, which may be associated with assembly of the Wilson and Bowers terranes.〈br〉〈br〉REFERENCE:〈br〉Adams, Christopher J (1997): Initial strontium isotopic signatures of Late Precambrian-Early Paleozoic metasediments from northern Victoria Land, East Antarctica. In: Ricci, G.A. (ed.), The Antarctic region: geological evolution and processes, Terra Antarctica Publication, Sienna, 227-231
Note:
This dataset is supplement to hdl:10013/epic.26834.d001
Language:
English
Keywords:
Datensammlung
DOI:
10.1594/PANGAEA.605207
URN:
urn:nbn:de:tib-10.1594/PANGAEA.6052072
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