Dwyka Gr
Period:
Carboniferous, Permian
Age Interval:
Middle – Late Pennsylvanian
Province:
Karoo Basin
Type Locality and Naming
Northern facies of Mbizane Fm; Northern facies of Elandsvlei Fm
Synonym:
Lithology and Thickness
Glacial to glacio-marine sediments (deep marine)
Lithology Pattern:
Glacial till
Relationships and Distribution
Lower contact
In the North, it is disconformable on glaciated surfaces on Precambrian bedrock in the north; in the South, unconformably or paraconformably overlies the Cape Supergroup (e.g., Witpoort Fm); and in the East, unconformably overlies the Natal Gr and Msikaba Fm.
Upper contact
Prince Albert Fm (conformable)
Regional extent
GeoJSON
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Fossils
Age
Age Span:
Beginning stage:
Moscovian
Fraction up in beginning stage:
0.4
Beginning date (Ma):
311.90
Ending stage:
Gzhelian
Fraction up in the ending stage:
0.44
Ending date (Ma):
301.57
Depositional setting
"The northern facies of the Dwyka Group rep- resents predominantly valley fill deposits left by retreating glaciers (Visser, 1983). The southern facies represents thick platform depositsof diamicton". Johnson et al., 1997.
Depositional pattern:
Additional Information
Compiler:
Rebecca Bobick (and Wen Du), modified from Fig. 2. from Catuneanu, O., et al., "The Karoo basins of south-central Africa", Journal of African Earth Sciences 43 (2005), 211-254