Graafwater Fm
Period:
Ordovician
Age Interval:
Middle Ordovician
Province:
Karoo Basin
Type Locality and Naming
Synonym:
Lithology and Thickness
It is a blanket of quartz sandstone and mudstone that accumulated when fault-controlled subsidence had ceased and the rifts were yoked together.
Lithology Pattern:
Clayey sandstone
Relationships and Distribution
Lower contact
Piekenierskloof Fm (conformable)
Upper contact
Peninsula Fm (conformable)
Regional extent
GeoJSON
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Fossils
Age
Age Span:
Beginning stage:
Floian
Fraction up in beginning stage:
0.7
Beginning date (Ma):
473.01
Ending stage:
Darriwilian
Fraction up in the ending stage:
0.8
Ending date (Ma):
460.43
Depositional setting
Depositional pattern:
Additional Information
Compiler:
Rebecca Bobick (and Wen Du), modified from Tankard, A., "Tectonic evolution of the Cape and Karoo basins of South Africa", Marine and Petroleum Geology 26 (2009) 1379–1412