Gamka Formation (1st Sandstone), Grootrivier (Devonian of South Africa)

Where: South Africa (32.6° S, 19.4° E: paleocoordinates 62.5° S, 150.5° W)

• coordinate stated in text

• local area-level geographic resolution

When: Gamka Formation (Bokkeveld Group), Late/Upper Emsian (402.5 - 391.9 Ma)

• Latest Emsian. Age call from ref. 9618.

• formation-level stratigraphic resolution

Environment/lithology: marine; fine-grained, medium, intraclastic sandstone

• Ref. 9618 gives interpretation of Bokkeveld Group as a series of shallowing-upward packages, with argillaceous unit below and arenaceous unit above. The shallowing upward sequence is interpreted as representing environments from the shelf up to deltaic systems. Most fossils come from lower mudstones, often in lenses.
• Ref. 9616 refers only to "sandstone". Ref. 9617, for formation as a whole, cites "Sandstone, fine- to medium-grained, thin- to thick- bedded, parallel laminated, planar cross-bedded, thin intraclast lenses, fossiliferous lenses"

Primary reference: R. D. F. Oosthuizen. 1984. Preliminary catalogue and report on the biostratigraphy and palaeogeographic distribution of the Bokkeveld fauna. Transactions of the Geological Society of South Africa 87:125-140 [M. Foote/M. Foote/M. Foote]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 35599: authorized by Michael Foote, entered by Michael Foote on 30.12.2003

Creative Commons license: CC BY (attribution)

Taxonomic list

 Cardiidia - Grammysiidae
 Protobranchia - Malletiidae
Nuculites sp. Conrad 1841 clam
 Bellerophontida - Plectonotidae
"Bellerophon ? laticarinatus" = Plectonotus laticarinata, "Bellerophon ? africanoides" = Ptomatis africanoides
"Bellerophon ? laticarinatus" = Plectonotus laticarinata Knod 1908 snail
"Bellerophon ? africanoides" = Ptomatis africanoides Cowper Reed 1925 snail
? Acanthodii indet. Owen 1846 spiny fish
listed as Acanthodian spine?
Crinoidea indet. Miller 1821 Sea lily
 Cladida -
 Tentaculitida - Tentaculitidae
 Productida - Chonetidae
 Spiriferida - Hysterolitidae
 Rhynchonellida - Leptocoeliidae