Mkanga Fm
Type Locality and Naming
Named after the Mkanga River in the Lower Zambezi Valley of northern Zimbabwe. Like the Angwa Sandstone, this formation was formally defined and named by P.M. Oesterlen in 1990 during a major lithostratigraphic revision of the western Cabora Bassa Basin, replacing earlier informal names for the local Lower Karoo mudstones. It is included in Ecca Gr
Synonym:
Lithology and Thickness
A thick, predominantly argillaceous (muddy) succession, estimated to reach between 600 and 800 meters in thickness. It consists mainly of massive, monotonous, pale grey to greenish-grey and sometimes reddish-brown mudstones and calcareous siltstones.
Relationships and Distribution
Lower contact
Conformably and transitionally overlies the carbonaceous shales, coals, and sandstones of the Kondo Pools Fm (the local equivalent of the Black Shale and Coal Gr / Wankie coal measures).
Upper contact
Unconformably overlain by the massive, coarse-grained fluvial deposits of the Angwa Sandstone Fm.
Regional extent
Extensively mapped in the northern rift basins of Zimbabwe (Mana Pools and western Cabora Bassa Basin) and extending eastward into Mozambique. Upper unit of the Lower Karoo Gr in the Cabora Bassa Basin. It is the direct regional chronostratigraphic and lithological equivalent of the Madumabisa Mudstone Fm in the adjacent Mid-Zambezi Basin, and roughly correlates with the lower Beaufort Gr (Adelaide Subgroup) in the Main Karoo Basin of South Africa.
GeoJSON
Fossils
Age
Depositional setting
Broad, shallow inland lakes and extensive, low-relief muddy floodplains.
Additional Information