An Assessment of Terrestrial Ecosystem Response to the End Permian Crisis, Karoo Basin, South Africa
The present study reports on an autochthonous forest-floor litter preserved by volcanic tuff, now devitrified, above a rooted, poorly developed paleosol at Wapadsberg Pass, in the Graaff-Reinet area, Eastern Cape Province. The gleyed protosol contains subvertical Vertebraria roots and is -70 m below the purported P/Tr boundary as defined by vertebrate biostratigraphy. The horizon is traceable over 1 km in lateral extent, occurring in both New and Old Wapadsberg Passes. The litter (O) horizon preserves not only leaves of aerial shrubs (Glossopteris) but also rhizomatous sphenopsid ground cover (Phyllotheca, Trizygia). To date, only Glossopteris leaves and stem debris have been recovered from -5 m below the reported boundary at Old Wapadsberg Pass.
A suite of zircons recovered from the tuffaceous horizon comprises grains that range in age from Neoproterozoic to the mid-Phanerozoic. Evidence indicates that the terrestrial response to the main marine pulse may not have been coincident.