Chronology of Hominid Occupation at Bir Tarfawi and Bir Sahara East, Based on the Epimerization of Isoleucine in Ostrich Eggshells

Abstract

Sediments and their associated biological remains contain primary information on past environmental conditions and proxy information on paleoclimate. To use such data in regional paleoenvironmental reconstructions requires an evaluation of their age, at least relative to other local deposits, and, for maximum information, their absolute age. In regions of continuous sedimentation, relative age control can be obtained from the lateral continuity of sedimentary environments. Most terrestrial Quaternary deposits, however, are characterized by complex depositional and erosional cycles and rapid facies change that preclude conventional stratigraphic correlations. In some instances, the proxy climate data themselves (eg. faunal or floral assemblages) can be used to correlate disjunct exposures, although such correlations may obscure important geographic trends.