Includes Lower Mixtite Formation
Period:
Tonian
Age Interval:
694–750 Ma
Province:
West Congo Basin / Bas-Congo region, DRC
Type Locality and Naming
Lithology and Thickness
diamictites: poorly sorted mud-supported conglomerates with angular and rounded clasts. Associated with basaltic lavas and feeder dolerite sills. Sturtian glaciation. Thickness: ≤ 400 m.
Lithology Pattern:
Glacial till
Relationships and Distribution
Lower contact
Underlain by the S2b Fm.
Upper contact
Overlain by the Sh1 Fm.
Regional extent
West Congo Belt (DRC, Republic of Congo, Gabon, NW Angola).
GeoJSON
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Fossils
Age
Anchor age: Sturtian glaciation (~750 Ma). Correlated to Mwale/Grand Conglomérat (CAC) and Chuos/Varianto (KDB).
Age Span:
Beginning stage:
Cryogenian
Fraction up in beginning stage:
0.31
Beginning date (Ma):
693.65
Ending stage:
Tonian
Fraction up in the ending stage:
0.89
Ending date (Ma):
750.80
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.