Denudational history along a transect across the Drakensberg Escarpment of southern Africa derived from apatite fission track thermochronology

Abstract

The denudational history of a ∼500 km long transect across the Drakensberg Escarpment on the high‐elevation passive margin of SE Africa is quantified on the basis of thermal history modeling of apatite fission track data for 15 deep borehole samples, supplemented by an additional 10 outcrop samples. A minimum of 4.5 km of denudation since formation of the margin ∼130 Myr ago is estimated for the coastal zone, with a marked Early Cretaceous episode of accelerated denudation broadly coincident with continental breakup. Samples from the Swartberg borehole (SW 1/67) located ∼30 km seaward of the present position of the Drakensberg Escarpment indicate a total depth of denudation of 3.1 ± 1.2 km s..