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 (e.g.
Nuculopsis),
gastropods (e.g.
Peruvispira),
scyphozoa (e.g.
Conularia),
crinoid stalks,
foraminifera (
Hyperammina,
Ammodiscus,
Glomospira,
Ammobacculites and
Spiroplectammina),
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 (Gzelian) 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 (297 Ma) was determined from zircons of a
tuffaceous bed sampled in a roadcut in the Western Cape Province, South Africa. == Fossil content ==