Assessing long-term habitability at an eastern Sahara oasis: ESR dating of molluscs and herbivore teeth at Dakhleh Oasis, Egypt

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• 作者：M.R. Kleindienst^a ; ^{maxine.kleindienst@utoronto.ca" class="auth_mail" title="E-mail the corresponding author} ; B.A.B. Blackwell^b ; ^c ; ^{Bonnie.A.B.Blackwell@williams.edu" class="auth_mail" title="E-mail the corresponding author} ; A.R. Skinner^b ; ^c ; ^{Anne.R.Skinner@williams.edu" class="auth_mail" title="E-mail the corresponding author} ; C.S. Churcher^e ; ^{rchurcher@shaw.ca" class="auth_mail" title="E-mail the corresponding author} ; J.M. Kieniewicz^d ; ¹ ; ^{jomakie@gmail.com" class="auth_mail" title="E-mail the corresponding author} ; J.R. Smith^d ; ^{jensmith@levee.wustl.edu" class="auth_mail" title="E-mail the corresponding author} ; N.L. Wise^b ; R.A. Long^c ; ² ; A.E. Deely^c ; J.I.B. Blickstein^c ; K.K.L. Chen^c ; A. Huang^c ; M.Q.D. Kim^c
• 关键词：Dakhleh Oasis ; Egypt ; Sahara ; Electron spin resonance ; Middle Stone Age ; Palaeoenvironments
• 刊名：Quaternary International
• 出版年：2016
• 出版时间：15 July 2016
• 年：2016
• 卷：408
• 期：part_PB
• 页码：106-120
• 全文大小：3803 K

文摘

In the northeastern Sahara, electron spin resonance (ESR) dating of when animals lived documents their habitability in Dakhleh Oasis, Egypt. A Middle Pleistocene paleolake(s) covered >1700 km². At eastern Locality Dak348, 10 m thick, remnant lacustrine marls yielded Pleistocene fauna, rare artefacts, and plant casts. No obvious unconformity exists within these deposits. From upper horizons, a hartebeest tooth ESR dated at 195 ± 11 ka, correlates with Marine Isotope Stage (MIS) 7, while molluscs from a stratigraphically higher horizon averaged 89 ± 10 ka, correlating with MIS 5a/b. At western Locality Dak006, upslope deflation has left a temporally mixed surficial lag. Numerous lagged tooth fragments, independently dated by ESR, correlate with MIS 5 through 17. Fragments from a slope sand unit correlate with MIS stages 3 through 6. One bovid tooth associated with Younger Middle Stone Age artefacts in the base of the sand dated at 84 ± 7 ka (MIS 5a/b). Molluscs from Romano-Byzantine backdirt at a breached artesian vent dated to 8–15 ± 1 ka, suggesting that ponds formed during MIS 1 and 2. Even without well defined sedimentary contexts, ESR frequency data indicate that the oasis was habitable for herbivores during at least twelve stages in the Mid-Late Quaternary, and, therefore, likely also for humans.