West Witwatersrand Gr
Period:
Mesoarchean
Age Interval:
Late Mesoarchean
Province:
Karoo Basin
Type Locality and Naming
Upward succession of the Hospital Hill Subgroup (Orange Grove Fm, Parktown Fm, Brixton Fm, Bonanza Fm), Government Subgroup (Promise Fm, Coronation Fm, Tusschenin Fm, Palmietfontein Fm, Elandslaagte Fm, Afrikander Fm) and Jeppestown Subgroup (Koedoeslaagate Fm, Reitkuil Fm, Barbrosco Fm, Crown Fm, Roodepoort Fm and Maraisburg Fm)
Synonym:
Lithology and Thickness
Lithology Pattern:
Sandstone
Relationships and Distribution
Lower contact
Dominion Gr (unconformable)
Upper contact
Regional extent
GeoJSON
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Fossils
Age
Arbitrarily assigned from 28% up in the "Randian" to 60% up the base of Witwatersrand => ca. 2980 to 2857 Ma.
Age Span:
Beginning stage:
Mesoarchean
Fraction up in beginning stage:
0.55
Beginning date (Ma):
2,980.00
Ending stage:
Mesoarchean
Fraction up in the ending stage:
0.8575
Ending date (Ma):
2,857.00
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.