Dear Dr. Turney, Although I myself is not an expert in this and specialize in carbonate isotopic comp of sediments and speleothems (paleocl.), I have a knowlege of a mid-continental site containing tree stumps and trunks buried in a sand deposit. They estimated to be 15-36 Ka. The place is near lake Baikal, Siberia. C14 had been done I guess on some of them and they have (I beleive) some sections taken already. If you are interested, I will dig up an e-mail address of a person there and forward it to you (all). Sincerely, Pavel. ===================================================== Pavel Romashkin Stable Isotope Lab, Department of Geological Sciences University of South Carolina, Columbia SC 29208 USA ph (803)777-7668 fax (803)777-6610