Angwa Sandstone
Geological formation of southern Africa
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The Angwa Sandstone is a geological formation of the mid-Triassic Cabora Bassa Basin [1] and Mana Pools Basin [3] of southern Africa, consisting mainly of sandstone.[4]
Massive Sandstone Mb.[1]
| Angwa Sandstone | |
|---|---|
| Stratigraphic range: Triassic ~ | |
| |
| Type | Geological formation |
| Unit of | Upper Karoo Group, Karoo Supergroup |
| Sub-units | Alternations Mb. Massive Sandstone Mb.[1] |
| Underlies | Pebbly Arkose Formation |
| Overlies | Lower Karoo Group |
| Lithology | |
| Primary | Sandstone |
| Other | Siltstone |
| Location | |
| Coordinates | 16.107°S 30.307°E[1] |
| Country | Mozambique, Zambia, Zimbabwe |
| Type section | |
| Named for | Angwa River, Zimbabwe |
| Named by | P.M. Oesterlen, Zimbabwe Geological Survey[2] |
  Angwa Sandstone (Zimbabwe) | |
Description
Stratigraphy
The Angwa Sandstone is the lowest formation in the Upper Karoo Group of the Karoo Supergroup, underlying the Pebbly Arkose Formation and overlying the Lower Karoo Group.[5] The formation is divided into two members: the Alternations Member and the Massive Sandstone (Chirambakadoma) Member.[1]
The Angwa Sandstone has been correlated to the Molteno Formation of the Great Karoo Basin, South Africa,[6][1] and to the Escarpment Grit of the Mid-Zambezi Basin.[7]
Lithology
The formation is a sedimentary unit, consisting mainly of fluvial sands and silts.[1]
It has been dated as covering rocks from much of the Triassic, with pollen and flora identified from the Induan, and Ladinian to Norian.[6][8]
Occurrence
The Angwa Sandstone Formation is found in Mozambique, Zambia, Zimbabwe, in the Mana Pools and Cabora Bassa Basins.
Fossil Content
| Pinales of the Angwa Sandstone | ||||
|---|---|---|---|---|
| Genus | Presence | Notes | Images | |
| Dadoxylon | Mbire District and Chirundu, Zimbabwe | |||
| Callistophytaceae (Pteridospermopsida) of the Angwa Sandstone | ||||
|---|---|---|---|---|
| Genus | Presence | Notes | Images | |
| Lepidopteris | Manyima River, Mbire District, Zimbabwe | |||
| Dicroidium | Manyima River, Mbire District, Zimbabwe | |||
| Ginkgoales of the Angwa Sandstone | ||||
|---|---|---|---|---|
| Genus | Presence | Notes | Images | |
| Sphenobaiera | Manyima River, Mbire District, Zimbabwe | |||