ESR Analyses for Herbivore Teeth from Dakhleh Oasis, Egypt: Constraining Pluvial Events in the Western Desert
Electron spin resonance (ESR) can date tooth enamel ranging from 5 ka to 5 Ma in age. From Dakhleh's Localities D006 and 348, 17 herbivore tooth fragments were dated with ESR. At 348, the CSS marls yielded Pleistocene bone fragments, MSA artefacts, snails, marsh grass macrofossils and stem casts, Alcelaphus, zebra, pig, and freshwater snails. At D006, sand dunes, deflation, and blowouts complicate the stratigraphy. The mid-Holocene lake deposits forms most of the surface, but blowouts expose red CSS mud. Several different layers were deflated onto the surface lag. Blowouts yielded Middle Pleistocene skeletal remains from Gazella, Phacochoerus, Loxodonta africana, Hippopotamus, Pelorovis antiquus, and Felis lybica. Although better cosmic dose rate modeling would improve their accuracy, the preliminary ESR ages indicate that mammals lived at Dakhleh during three periods. Teeth dated at 58 ± 5 ka, correlating with early Oxygen Isotope Stage (OIS) 3, 109-111 ± 10 ka (OIS 5c), 127-130 ± 15 ka (OIS 5e), and 159-184 ± 15 ka (OIS 6c). The herbivore frequency data, therefore, indicate that at least four pluvials made the Western Desert more habitable during the late Pleistocene.