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The Cherry Creek Rockshelter is an archaeological site in central Colorado, located within modern-day Castlewood Canyon State Park near Franktown, Colorado. Current research indicates that it was used by Native American inhabitants beginning in the Archaic period. The site is situated on the Palmer Divide, which allowed for a unique prehistoric environment that contributed to an abundance of food and water sources, as well as lithic materials for tool-making. These factors, combined with the structure and situation of the shelter itself, made the site a particularly attractive environment for prehistoric peoples to settle in. Archaeological study of the site began in 1955, with the most current original research concluding in 2002. ==Geography== The park and archaeological site are located within the northern reaches of the Black Forest, a relatively isolated area of montane forest surrounded by drier grasslands. This forest is nurtured by the increase in elevation provided by the Palmer Divide, which allows for a higher amount of precipitation than is typical for central Colorado. The site is situated on the western bank of Cherry Creek, a tributary of the South Platte River that flows north through the park. With its maximum exposure to the south, the shelter is in an ideal position to shield inhabitants from cold northern winds while allowing for abundant solar radiation to warm the site.〔Tchakirides 16〕 This area of Colorado has historically had a diverse ecosystem, with sources of abundant food, water, shelter, and lithic materials for stone tool manufacture. Such factors encouraged human settlement of the area. This region experienced a notable diversity of floral and faunal species similar to those of the nearby Rocky Mountain foothills, but with a zonation of larger plants that differentiates the ecosystem of the Palmer Divide from similar environments. Prehistoric animal species included bison, antelope, deer, rabbits, and other animals that would have provided an abundant and diverse food source for native peoples. Nearby water sources included not only Cherry Creek, but also fresh water springs that occurred within the rockshelter and which contributed to the development of the site (Tchakirides 16-18). The sedimentation of the area directly contributed to the formation of the rockshelter. The bedrock is composed of Denver and Dawson formations, deposited in the late Cretaceous to Paleogene, and overlaid with Castle Rock conglomerate. The Castle Rock conglomerate is harder than the relatively soft Denver and Dawson formations. Groundwater moving between these two major layers erodes the lower, softer formations and leaves the harder Castle Rock conglomerate behind. Where these layers form outcrops, the same groundwater erosion may produce natural caves as seen in the Cherry Creek rockshelter.〔Tchakirides 19〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Cherry Creek Rockshelter」の詳細全文を読む スポンサード リンク
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