RELICT FORESTS AND DETRITUS EXPOSED BY RECEDING SNOW AND ICE IN THE GREATER YELLOWSTONE AREA, USA

In the last two decades, archaeological and paleobiological sites have been identified in association with numerous kinetically stable ice patches in western North America (e.g., Greer et al. 2021). Unlike glaciers, ice patches exhibit little internal deformation or movement. Consequently, they can preserve fragile perishable materials including artifacts, such as arrows and atlatl darts; faunal remains; and relict plant communities. Archaeological objects from ice patches offer an unparalleled view of human adaptation because they are often relatively complete and recovered in the systemic context in which they were used and lost (or left). So too, paleobiological specimens preserved in ancient ice provide a unique entrée to alpine paleoecology—including dendrochronological records—that can help contextualize human activity.

It should be no surprise that changing temperature and precipitation patterns are degrading the archive of archaeological and paleontological information contained in ice patches. In fact, paleobiological specimens are far more common than archaeological material at ice patch locations; however, only a few studies in the Greater Yellowstone Area (GYA) address these samples directly (e.g., Stahle 2022). This paper will describe some of the paleobiological materials identified in GYA ice patches, including an ancient tree stand with a calibrated radiocarbon age of 4442 BP (Calib 8.2) on Hurricane Mesa (Wyoming) that was known to colleague Ken Pierce, whom this session celebrates. The paper posits directions for future research, which include obtaining additional samples for climatic reconstructions following Stahle (2022), as well as exploring the possibility of assessing temporal changes in isotopic composition.

References Cited.

Greer, S., C. Thomas, K. Chambers, D. Tirlea, A. Osicki, T. Kristensen, and C. Lee, 2021, High Elevation North America: Ice Bound Histories from Yukon, Alberta and the Greater Yellowstone Area, Archäologie in Deutschland, Sonderheft Vol. 21, Issue 2, p. 70-80.

Stahle, D., 2022, A Forest Entombed in Ice: A Unique Record of Mid-Holocene Climate and Ecosystem Change in the Northern Rocky Mountains, U.S.A. [MSc thesis]: Bozeman, Montana State University.