11 Geological Background of Early Hominid Sites in Africa

Abstract

Hominid remains are rare elements in the fossil record. Probably the small population sizes of early hominids, in combination with preservation constraints, limit the probability of a higher frequency of fossil discoveries. The early evolution of mankind appears to be a Pan‐African story, even though the distribution pattern of remains concentrates on eastern and southern Africa. More recent findings from the Chad Basin in central Africa demonstrate that fossil hominid remains are not restricted to the eastern part of Africa. The success of exploration in paleoanthropology depends on the discovery of appropriate sediment layers, mainly lake and river deposits with an upper Miocene through Pleistocene age. Knowledge of the geological framework is of great importance in evaluating the potential for fossil preservation in a certain area. To date, three major types of geological megastructures have yielded almost all fossil remains of early hominids: the East African Rift Valley (EARV), the intracratonic basin of Lake Chad, and the fossil‐rich cave deposits in South Africa. Each of these regions provides a unique sedimentary setting bearing fossil‐rich layers comprising a specific time‐span within the last few million years.