Geological age of the Claypool site, northeastern Colorado

American Antiquity



Artifacts related to the Cody complex occur in medium-grained sand that is spread as a blanket eolian deposit a few feet thick in the Claypool site area, Washington County, Colorado. The artifact-bearing sand lacks noticeable dunal topography and lies unconformably on marl of Yarmouth age and on waterlaid coarse sand and fine gravel of Kansan age that underlie the marl. The deposits underlying the artifact-bearing sand are much too old to date the artifacts precisely, but the physical characteristics of the artifact-bearing sand suggest that it was deposited under conditions cool and dry, rather than warm and dry, possibly during retreat of Valders ice that began about 10,000 years ago. A moderately mature Brown Soil about 5 feet thick developed on the sand, possibly about 7000 to 5000 years ago during a moist phase of the Thermal Maximum. Thus, the artifacts are possibly 10,000 to 7000 years old. Deposits which overlie the artifact-bearing sand reflect several episodes of erosion and sedimentation that are inferred to represent climatic changes.

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Publication type Article
Publication Subtype Journal Article
Title Geological age of the Claypool site, northeastern Colorado
Series title American Antiquity
DOI 10.2307/276202
Volume 26
Issue 2
Year Published 1960
Language English
Publisher Society for American Archaeology
Description 8 p.
First page 215
Last page 222
Country United States
State Colorado
Other Geospatial northeastern Colorado
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