HUMAN OCCUPATIONS ACROSS THE PLEISTOCENE-HOLOCENE TRANSITION ON THE GREAT PLAINS: GEOMORPHIC AND REGIONAL PATTERNS

A current synopsis of geomorphic evidence from selected Great Plains archaeological sites of Clovis, Folsom, and later Paleoindian ages is provided. Archaeological site occurrences and regional patterns of artifact finds are discussed by time period: pre-11,000, 11,000-10,000, and 10,000-8,500 radiocarbon yrs. BP, and by (geomorphic) depositional context: stream valleys, gullies, playas, and dunes. The number of recorded sites with detailed geomorphic and stratigraphic data is small, so existing patterns must be viewed with consideration of probable sampling bias. There are not enough sites within each time period to enable a statistically viable assessment of potential changes in land use patterns which may have resulted from environmental changes associated with the Pleistocene-Holocene transition. It is likely that there was recurrent use of upland playas (e.g., the Clovis-age Miami site), dunefields (e.g., the Folsom-age Shifting Sands site and the later Paleoindian Milnesand site), stream valleys (e.g., the Clovis-age Aubrey site, the Folsom-age Waugh site, and the later Paleoindian Plainview site), and gullies (e.g., the Folsom-age Cooper site and later Paleoindian Olsen-Chubbuck and Norton sites). The available evidence, however, provides important clues that aid in the interpretation of regional patterning in the archaeological record.

Within the Plains of Texas, Oklahoma, Kansas, eastern Colorado, Nebraska, and South Dakota, there are strong patterns in the distribution of diagnostic Paleoindian artifacts reflecting a combination of prehistoric population patterns, modern recording biases, and regional geomorphic processes. As examples, the documented occurrence of Clovis points diminishes dramatically from south to north in the Plains. This may reflect, in part, prehistoric population density or time-transgressive longevity of this technological tradition, as the oldest dated Clovis component is in the southern Plains. In contrast, the relatively low frequency of Folsom artifacts in western Kansas, compared to adjacent regions, may reflect a distinctive geomorphic history (erosion and/or deep burial) during or following the Pleistocene-Holocene transition.