The geological and faunal context of Late Miocene hominid remains from Lukeino, Kenya

Hominid fossils have been recovered from four localities within the Late Miocene Lukeino Formation, Tugen Hills, Kenya. The sediments from which the fossils came consist of fluvial and shallow lacustrine deposits. Some of the specimens are coated in a thin layer of carbonate of organic origin, suggesting deposition and preservation in slightly alkaline water, while others are riddled with superficial cracks indicating exposure at the surface prior to burial, Radioisotopic age determinations from lavas underlying and overlying: the Lukeino Formation, and from crystals from the sediments themselves, indicate an age of ca 6 Ma for these hominids. (C) 2001 Academie des sciences / Editions scientifiques et medicales Elsevier SAS.