Mesa Verde National Park

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Alexandra Ellis Exam 1 September 23rd, 2015

Mesa Verde National Park

Mesa Verde National Park, established in 1906 by President Roosevelt, is a part of the Colorado Plateau and lies in the Southwestern corner of Colorado. The park covers about eighty-one square miles and the entire Mesa Verde area which contains the park, is about five hundred and twenty square miles. (nationalparkguru.com) The park was established as a “national park” to protect archaeological sites made from the ancestral Anasazi (Puebloan) people who built cliff dwellings within alcoves in the walls of the canyons. The park is the biggest preserved area for archaeological sites in the United States. Mesa Verde has many different geological …show more content…

The most abundant rock types would be: sandstones, shales, siltstones and mudstones. Although the Mesa might look flat, it is a cuesta that slopes to the south. Dakota Sandstone is the primary rock bed that lays under the park. This particular rock forms the escarpment of Mesa Verde. (Harris et al. 96). Mancos Shale is another layer of rock on top of the Sandstone. Sandstone rimrock is the top and youngest layer of the park. The textbook states, “Because the mancos has a high clay content, it expands when wet and causes slumping and sliding so that the road has to be repaired frequently”. (Harris et al. 96) The mancos consist of fine-grained sandstones, shales and mudstones. The main group of rock units would be the late cretaceous Mesaverde Group. This group of sedimentary layers consists of the Point Lookout Sandstone, the Cliff House Sandstone and Menefee. These formations consist mainly of sandstones, shales, silts and muds. Loess covers the top of Mesa Verde National Park which makes the area very …show more content…

Because the park shifts south at an angle, the conditions are ideal for alcove formation. These alcoves were once used as cliff dwellings by the Anasazi Indians. Alcoves are formed in the Cliff House Sandstone formations in the canyons. This formation in particular is the youngest bedrock of the Mesa Verde. The formation is about 400 feet in thickness and forms the bold, orange cliffs in the canyons. (Harris et al. 99) The canyons consist of porous sandstone formations and shale formations. When wet, the sandstone holds water and the walls to turn into a cement. Over time the cement dries, the sandstone freezes and expands in the winter thus causing the sandstone to chip out hollow areas in the canyon walls. Because the Shale formation is not permeable like the sandstone, it keeps water pooled in a certain area and this determines how shallow or deep the alcoves are formed. This is also how the springs are formed in the area. The process of alcove formation has slowed down over time. The wetness of the Cliff House formations and humid climate around canyon walls is what allowed the alcoves to be produced

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