Mesa Verde National Park is in the Colorado Corner of the Four Corner area. When the Mesa Verde region was uplifted, the streams cut themselves into pediments and divided into two components. One was the McElmo Creek which flows to the west and the other was the Mancos River which drains the cuesta. The Mesa Verde is a cuesta that slopes gently to the south. A cuesta is a hill with a step on one side and a gentle slope on the other. The steep on the Mesa Verde is a 2,000 foot high cliff on the north side of the park. It’s formed by a resistant sandstone. The dip of the sedimentary bed is slightly steeper than the slope of the Mesa surface. The Dakota sandstone which underline just about most of Colorado, grows west of the Mesa Verde National
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It forms a long slope of escarpment. Since the Mancos shale has a high clay content that makes it expand when it gets wet. The Mancos in the Mesa Verde are fine grained sandstones, mudstones, and shale’s. There are three formations comprising the mesa Verde. They are the Point Lookout sandstone, Menefee Formation, and the Cliff House sandstone. These formations reflect the changes that were occurring at the end of the cretaceous time. The Point Lookout sandstone forms the rims of the escarpment on top of the park. The sediment that make up the formations is about 400 feet thick. The upper layer of the sandstone contains …show more content…
The Cliff House had many openings. On the top of the Mesa, snow was melting and rain was soaking in and goes through to the sandstone until it reaches the shale bed. Even though there were many openings in the Cliff House, they were small openings because the water would get stuck. Ground water was dissolving cement and loosening sheets and blocks of sandstone. Because of the seasonal freezing and thawing of ground water, it breaks up the bedrock. Exfoliation, mass wasting, and trickling water remove the lessened material enlarging hollows into alcoves. A final uplift caused the streams to down cut rapidly, removing sediment and creating canyons. If the bedrock is wetter, then older alcoves will form, deepen, and then collapse within the canyons walls, while new alcoves are being created. Headward erosions in the canyon, made a drainage pattern, which was really intense during the cooler and more humid climates. In present time, we have a much drier climate, which is causing the erosional process to move at a much slower rate. There is one unique alcoves in the Mesa Verde National park, and that is the Step House. It is unique because there are two separate occupations in the same site. A Modified Basket maker site, which happens to be situated between the old stone steps on the south and large boulders to the north. The rest of the alcove contains a masonry
It forms a long slope of escarpment. Since the Mancos shale has a high clay content that makes it expand when it gets wet. The Mancos in the Mesa Verde are fine grained sandstones, mudstones, and shale’s. There are three formations comprising the mesa Verde. They are the Point Lookout sandstone, Menefee Formation, and the Cliff House sandstone. These formations reflect the changes that were occurring at the end of the cretaceous time. The Point Lookout sandstone forms the rims of the escarpment on top of the park. The sediment that make up the formations is about 400 feet thick. The upper layer of the sandstone contains …show more content…
The Cliff House had many openings. On the top of the Mesa, snow was melting and rain was soaking in and goes through to the sandstone until it reaches the shale bed. Even though there were many openings in the Cliff House, they were small openings because the water would get stuck. Ground water was dissolving cement and loosening sheets and blocks of sandstone. Because of the seasonal freezing and thawing of ground water, it breaks up the bedrock. Exfoliation, mass wasting, and trickling water remove the lessened material enlarging hollows into alcoves. A final uplift caused the streams to down cut rapidly, removing sediment and creating canyons. If the bedrock is wetter, then older alcoves will form, deepen, and then collapse within the canyons walls, while new alcoves are being created. Headward erosions in the canyon, made a drainage pattern, which was really intense during the cooler and more humid climates. In present time, we have a much drier climate, which is causing the erosional process to move at a much slower rate. There is one unique alcoves in the Mesa Verde National park, and that is the Step House. It is unique because there are two separate occupations in the same site. A Modified Basket maker site, which happens to be situated between the old stone steps on the south and large boulders to the north. The rest of the alcove contains a masonry