Lower Karoo Fm
Type Locality and Naming
Metangula Basin (Mozambique). Noted as a foundational lithostratigraphic division within the Karoo-aged Metangula Basin, located near the border of Mozambique and Tanzania. Like the "Middle Karoo," it is often utilized as a broad formational or sequence descriptor for the lowermost, oldest sediments filling this specific rift graben. Included in Dwyka Gr in Metangula Basin (Mozambique)
Synonym:
Lithology and Thickness
Composed of a basal terrestrial sequence that typically includes glacial or proglacial deposits. In regional stratigraphy, these basal Karoo units consist of diamictites (tillites), poorly sorted conglomerates, and interbedded sandstones and mudstones that represent the initial fill of the rift valleys.
Relationships and Distribution
Lower contact
Rests unconformably upon the ancient Precambrian crystalline basement, marking a massive temporal hiatus prior to the initiation of Karoo sedimentation.
Upper contact
Conformably to semi-conformably overlain by the coal-bearing Middle Karoo Fm.
Regional extent
Geographically restricted to the deepest portions of the Metangula Basin in northern Mozambique. Correlates broadly with the Dwyka Gr and basal Ecca Gr equivalents of the main and eastern African Karoo rift basins.
GeoJSON
Fossils
Age
Depositional setting
Intracratonic rift basin environments.
Additional Information