Butzer, K. W.; Stuckenrath, Robert, Jr.; Bruzewicz, A. J.; Helgren, D. M.
(1978)
The Gaap Escarpment is a dolomite cuesta demarcating the southeast margin of the Kalahari. Since Miocene-Pliocene times, thick masses of lime tufa have repeatedly accumulated at several points along this escarpment, and ...