Transvaal-Griqualand West Gr
Period:
Siderian, Rhyacian
Age Interval:
latest Siderian through Rhyacian
Province:
Karoo Basin
Type Locality and Naming
Complex of a generalized upward succession of the Griquatown Gr, Campbell Gr and Chuniespoort Gr of andesites-dolomite-limestone, Postmasburg Gr and Pretoria Gr of sandy claystone, Dullstroom Fm of basaalt, Rooiberg Gr of volcanics, and Loskop Fm of sandstone
Synonym:
Lithology and Thickness
Lithology Pattern:
Relationships and Distribution
Lower contact
Godwan Fm (conformable)
Upper contact
Bushveld Complex Gr (conformable)
Regional extent
GeoJSON
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Fossils
Age
Span from Walraven's diagram (base assigned 35% up from 2500Ma = 2325 Ma) to ca. 2050 Ma (base of Bushveld Complex Gr)
Age Span:
Beginning stage:
Rhyacian
Fraction up in beginning stage:
0.0
Beginning date (Ma):
2,300.00
Ending stage:
Siderian
Fraction up in the ending stage:
0.875
Ending date (Ma):
2,325.00
Depositional setting
Depositional pattern:
Additional Information
Compiler:
Rebecca Bobick (and Wen Du), modified from Walraven, F., Armstrong, R.A., and Kruger, F.J., A chronostratigraphic framework for the north-central Kaapvaal craton, the Bushveld Complex and the Vredefort structure, Tectonophysics, 171 (1990), 23-48.