Ganigobis Formation


The Ganigobis Formation is a Late Carboniferous to Early Permian geologic formation of the Dwyka Group in the ǁKaras Region of southeastern Namibia and the Northern Cape of South Africa. The widespread formation was deposited in the Aranos and Karoo Basins of southern Africa.

Description

The Ganigobis Formation is an extensive unit with a maximum thickness of evidenced in the Vreda borehole. The conglomerates, sandstones, shales and tuff of the formation were deposited in a glacio-lacustrine to marine environment. The Ganigobis Formation provides fossil fish as well as bivalves, gastropods, scyphozoa, crinoid stalks, foraminifera, sponges and sponge spicules, radiolaria, coprolites and permineralised wood.
Zircons of the Ganigobis Shale Member yield SHRIMP-ages of 302-300 Ma. This dates the uppermost part of the second deglaciation sequence in southern Namibia to the
Late Carboniferous and provides a minimum age for the onset of Karoo-equivalent marine deposition. The age of the uppermost argillaceous part of the third deglaciation sequence was determined from zircons of a tuffaceous bed sampled in a roadcut in the Western Cape Province, South Africa.

Fossil content

Among others, the following fossils are reported from the formation:
;Fish