Forest Sandstone

The Forest Sandstone is a geological formation in southern Africa, dating to roughly between 200 and 190 million years ago and covering the Hettangian to Sinemurian stages of the Jurassic Period in the Mesozoic Era. As its name suggests, it consists mainly of sandstone.

Fossils of the prosauropod dinosaur Massospondylus and the primitive sauropod Vulcanodon have been recovered from the Forest Sandstone.

Description
The formation is a sedimentary unit, consisting mainly of aeolian sands and silts with interbedded fluvial sediments, laid down during a period of increasing aridity.

Extent
The Forest Sandstone is found in Botswana, Zambia and Zimbabwe, in the Mid-Zambezi, Mana Pools, Cabora Bassa and Limpopo Basins, with its greatest thickness in the Cabora Bassa Basin.

Age
The formation is dated at 200 to 190 Ma.

Stratigraphy
The Forest Sandstone is the penultimate formation in the Upper Karoo Group of the Karoo Supergroup, lying above the Pebbly Arkose Formation and below the Batoka Formation. In the Thuli Basin it is sometimes referred to as the Samkoto Formation.

The Forest Sandstone has been correlated to the Clarens Formation of the Great Karoo Basin in South Africa.

Hydrogeology
The Forest Sandstone is the major groundwater-bearing unit of the Upper Karoo Group.