Sh7 Fm
Period:
Cryogenian
Age Interval:
655–660 Ma
Province:
West Congo Basin / Bas-Congo region, DRC
Type Locality and Naming
Synonym:
Reference section:
Lithology and Thickness
dark-grey siliceous shale with clayey limestone nodules; banded calcareous siliceous shale; greyish-green siliceous shale
Lithology Pattern:
Claystone
Relationships and Distribution
Lower contact
Underlain by the Sh6 Fm.
Upper contact
Overlain by the Sh8 Fm.
Regional extent
West Congo Belt (DRC, Republic of Congo, Gabon, NW Angola).
GeoJSON
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Fossils
Stromatolites (in Sekelolo limestones).
Age
Interpolated by thickness between 650–694 Ma
Age Span:
Beginning stage:
Cryogenian
Fraction up in beginning stage:
0.77
Beginning date (Ma):
654.55
Ending stage:
Cryogenian
Fraction up in the ending stage:
0.71
Ending date (Ma):
659.65
Depositional setting
Post-Sturtian open marine carbonate platform; two transgression-regression cycles (Cahen, 1954; Frimmel et al., 2006).
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.