Abstract:
 

The ca. 10,900 14C yr BP onset of the Younger Dryas cold reversal event is so closely coincidental to the demise of Clovis that it could well have been a causal factor in many regions. Yet, as catastrophic as this event may have been to Clovis survival, and probably landscape stability in general, in some settings the harsh climate also promoted rapid protective sealing of Clovis surfaces. The three locations addressed are geographically diverse, and during the Holocene their respective soils developed along markedly different genetic pathways. Nevertheless, they are linked by notable similarities in site formation. Younger Dryas deposits form culturally sterile zones between Clovis and Early Archaic occupations, and even though the locations are associated with major rivers, these deposits are largely eolian. At Cactus Hill they consist of eolian sands of relatively local origin, whereas on the Delmarva Peninsula loessial silts covering Clovis surfaces are many kilometers in extent. A more variable mix of probable loessial silts and over-bank alluvium overlies Clovis at Shawnee Minisink. Also, possibly echoing earlier Pleistocene conditions, Younger Dryas deposits are similar to those beneath Clovis.