2003 Seattle Annual Meeting (November 2–5, 2003)

Paper No. 4
Presentation Time: 8:00 AM-12:00 PM

NEW AND CORRECTED RADIOCARBON AGES FROM THE SOUTHERN PUGET LOWLAND, WASHINGTON


POLENZ, Michael, WALSH, Timothy J., LOGAN, Robert L. and SCHASSE, Henry W., Washington Department of Natural Resources, Division of Geology and Earth Resources, P. O. Box 47007, Olympia, WA 98504-7007, michael.polenz@wadnr.gov

During the 1960s, a laboratory error at the University of Washington compromised several radiocarbon age estimates of the Olympia beds from the southern Puget Lowland. Because the error was discovered after many of the dates had entered the literature, a misunderstanding of the ages of late Pleistocene sediments in the southern Puget Lowland has never been fully purged from the geological literature, and many workers remain unaware of the discrepancy. Recent geologic mapping in the southern Puget Lowland has greatly improved the data density of radiocarbon age estimates for that region, and we have resampled some of those originally reported. As a result, the dating of late Pleistocene sediments in the southern Puget lowland has improved markedly. We present an updated summary of radiocarbon age estimates from the southern Puget lowland and include a review of the early, erroneous age estimates.