GSA Annual Meeting in Seattle, Washington, USA - 2017

Paper No. 84-32
Presentation Time: 9:00 AM-5:30 PM


ADAMS, Betty L.1, BARTON, Bax R.2, KLEINKNECHT, Gary C.3, LAST, George V.3, MAULDIN, Bill1, MAULDIN, Kim1, AUSTIN, Curtis J.1, DETRICK, King1 and MARA, Neil1, (1)Mid-Columbia Basin Old Natural Education Sciences (MCBONES) Research Center Foundation, Kennewick, WA 99338, (2)Burke Museum of Natural History and Culture & Quaternary Research Center, University of Washington, Box 351310, Seattle, 98195, (3)Ice Age Floods Institute, Kennewick, WA 99338,

Here we document a partial, fragmented artiodactyl cannon bone recovered in the fall of 2012 at the Coyote Canyon South Hill-Mauldin Site (CCSH-MS) in the Horse Heaven Hills of south-central Washington. CCSH-MS is located at 46o09.552’ N and -119o16.125’ W [R28E, T8N, sec 23] at an elevation of ~314 m asl., and is roughly 300 m SW of the Coyote Canyon Mammoth Site ( The specimen is considerably eroded, and exhibits late stage 2-early stage 3 weathering. Adequate morphological characteristics remain on the bone to facilitate a taxonomic diagnosis from within the Order:Artiodactyla and Family:Camelidae. We identify this specimen through morphometric analysis as a partial right metatarsal of Camelops hesternus Leidy 1854 (“Yesterday’s camel”). A single sample for radiocarbon analysis was collected from this metatarsal, and submitted to Beta Analytic, Inc. (Miami, FL). This sample yielded a date of IRMS AMS 21010±70 BP (Beta 45508), suggesting an early LGM calibrated age range of 25,260-25,480 [average 25,370] calBP (at 68% probability), with a range of 25,140-25,580 [average 25,360] calBP (at 95% probability). Isotope analysis on this specimen yielded scores of -18.9 (δ13C) and +7.2 (δ15N), suggesting a terrestrial LGM diet dominated by C3 vegetation. The bone was found in very fine sandy silt sediments, within slackwater facies of Ice Age flood deposits. The depositional date of this find is further constrained by a lower limiting [terminus post quem] OSL date of 16.48±2.44 ka (USU CCCS-OSL-05), recovered from sediments sampled ~50 cm below the metatarsal. Both the weathered bone taphonomy, and the discrepancy of its radiocarbon date with its OSL stratigraphic depositional context suggest that the bone was plucked from nearby older strata and redeposited in later flood deposits. This find remains significant as one of the earliest radiocarbon dated and geographically well documented Camelops hesternus specimens from the Columbia Plateau of western North America.