Biostratigraphy of the lower Burgersdorp Formation (Beaufort Group; Karoo Supergroup) of South Africa – implications for the stratigraphic ranges of early Triassic tetrapods
Date
2005
Authors
Neveling, J.
Hancox, P. J.
Rubidge, B. S.
Journal Title
Journal ISSN
Volume Title
Publisher
BERNARD PRICE INSTITUTE FOR PALAEONTOLOGICAL RESEARCH
Abstract
The Beaufort Group (Karoo Supergroup) of South Africa comprises a thick sequence of fluvio-lacustrine sedimentary rocks that
accumulated in a landlocked, intracratonic foreland basin in southwestern Gondwana during the Middle Permian to Middle Triassic. To
the south this basin was bounded by the Cape Fold Belt, which acted as the major source of both sediment and discharge. Rocks of the
Beaufort Group are renowned for their rich fossil record and eight tetrapod-based biozones are currently recognized. The uppermost
two biozones of the Beaufort Group, the Lystrosaurus and Cynognathus assemblage zones, record terrestrial biotic recovery following the
Permo-Triassic mass extinction event. Stratigraphic overlap between these biozones occurs in the proximal sector, but their separation
by an unconformity in the distal sector reflects the incomplete preservation of the sequence in this part of the basin. Our results afford
chronostratographic control that impacts on current theories on the development of the Karoo Basin, and on the relative age of the
sequence.