S2b Fm
Period:
Tonian
Age Interval:
750–764 Ma
Province:
West Congo Basin / Bas-Congo region, DRC
Type Locality and Naming
Synonym:
Reference section:
Lithology and Thickness
dark shale with interbedded calcareous sandstone; alternating shale and quartzite. Upper Sansikwa. Thickness: 200–250 m.
Lithology Pattern:
Sandy claystone
Relationships and Distribution
Lower contact
Underlain by the S2a Fm.
Upper contact
Overlain by the Lower Diamictite (former 'Mixtite') Fm.
Regional extent
West Congo Belt (DRC, Republic of Congo, Gabon, NW Angola).
GeoJSON
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Fossils
Age
Interpolated by thickness (14%) between 750–850 Ma
Age Span:
Beginning stage:
Tonian
Fraction up in beginning stage:
0.89
Beginning date (Ma):
750.80
Ending stage:
Tonian
Fraction up in the ending stage:
0.84
Ending date (Ma):
764.80
Depositional setting
Depositional pattern:
Additional Information
Compiler:
Cailteux, J.L.H., Delpomdor, F.R.A., & Ngoie Ndobani, J.-P. (2015). The Neoproterozoic West-Congo 'Schisto-Calcaire' sedimentary succession from the Bas-Congo region (Democratic Republic of the Congo) in the frame of regional tentative correlations. Geologica Belgica, 18/2-4, 126–146.