Across the high plains of the United States, sedimentary strata ranging in
age from Cretaceous to Tertiary were deposited in a shallow epicontinental
seaway in extensive horizontal layers. These strata are generally composed
of fine sandstone, siltstone, shale, and volcanic ash and are very easily eroded.
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Stream incision into these loosely consolidated deposits combined with effects
of weathering and erosion resulted in formation of "badlands" -
a highly irregular landform composed of complex gullies with little or no
soil or vegetation.
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At Badlands National Park in South Dakota, USA, this landform is very well
developed in sedimentary strata from the Tertiary Period, as these Virtual Vistas illustrate. The exposed bluffs of semi-consolidated
sedimentary materials are continually changing as wind and water sculpt the
land surface.
Erosion is so efficient, no soil forms on the exposed slopes, and vegetation
cannot gain a foothold in the crumbling debris. The lack of vegetation enhances
the efficiency of wind and water erosion in this landscape.
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To learn more about Badlands National Park, visit the National
Park Service website.