OBRUCHEVELLA, A CYANOBACTERIUM FROM UPPER PROTEROZOIC OF CONGO - IMPLICATIONS IN THE PROBLEM OF AGE OF THE SCHISTO-CALCAIRE GROUP AND OF THE UPPER PROTEROZOIC GLACIATION
P. Alvarez et al., OBRUCHEVELLA, A CYANOBACTERIUM FROM UPPER PROTEROZOIC OF CONGO - IMPLICATIONS IN THE PROBLEM OF AGE OF THE SCHISTO-CALCAIRE GROUP AND OF THE UPPER PROTEROZOIC GLACIATION, Comptes rendus de l'Academie des sciences. Serie II. Mecanique, physique, chimie, astronomie, 320(7), 1995, pp. 639-646
The Schisto-calcaire Group of the Proterozoic sedimentary cover of the
Central Africa Craton rests upon the Diamictite superieure Formation
(Cryogenian). Some data suggest an early Neoproterozoic III age (betwe
en 650 and 630 Ma) for this Group, In Congo, a microfossil assemblage
has been detected in talc oolites and intraclasts from the Oolithe de
Kisantu Formation of the Schisto-calcaire Group. It includes several s
pecies of the filamentous cyanobacterium Obruchevella Reitlinger. This
assemblage has been reported in a number of regions near the Precambr
ian-Cambrian boundary. Therefore the stratigraphic position of the Sch
isto-calcaire Group and of the Diamictite superieure Formation must be
reconsidered.