TOWARDS A MAGNETOSTRATIGRAPHY OF THE TERRESTRIAL PERMIAN-TRIASSIC BOUNDARY

In order to understand the dynamics of the Permian-Triassic extinction, precise temporal correlation between well-preserved boundary sections is essential. The Karoo basin of South Africa preserves a complete terrestrial record across this interval that, in theory, should be able to provide magnetostratigraphic constraints for correlation into the marine realm. Biostratigraphy provided primarily by Lystrosaurus, Dicynodont, and other macrovertebrate zones across many intervals indicates that the sedimentation was continuous. Alternating field and progressive thermal demagnetization of paleomagnetic samples from eastern and western Lootsberg Pass, Komando Drift, and Charlton Flats areas shows varying degrees of thermal overprinting by dolerite dike intrusion that has pervasively remagnetized many South African rocks, but in some sections a primary characteristic remanent magnetization shows dual polarities in the vicinity of the boundary interval with a positive baked contact test. Completed demagnetization data from these sections with polarities tied into preliminary biostratigraphic sections will be presented and compared to published results of the magnetostratigraphy of marine P-Tr sections.