Dip slope
A dip slope is a geological formation often created by erosion of tilted strata.[1] Dip slopes are found on homoclinal ridges with one side that is steep and irregular (an escarpment) and another side, the dip slope, that is generally planar with a dip parallel to the bedding.[2] The orientation of the dip slope is referred to as the strike.
Formation
Some rocks (usually softer ones) erode more rapidly than others. For example, shale most frequently erodes faster than limestone. In situations like this, an entire layer of the easily erodible rock can be weathered away while a layer of a more durable rock will remain largely unchanged. This results in a nearly flat surface created by the top of the more durable layer. When this happens to beds that are not tilted mesas are formed. With tilted beds, structures called cuestas and hogbacks are formed. Mesas will have a flat top, while cuestas and hogbacks will look like ridges, with one side that is a dip slope and a steeper escarpment on the other.
Dip slopes can also be formed by igneous structures such as sills. Any generally planar geological structure can form dip slopes, when it is tilted away from horizontal.
Landslides
Dip slopes are quite prone to landslides, due to the dipping flat erosional surface. Large sheets of rock have a tendency to slide down dip slopes.
See also
References
- ^ "Cuesta, or homoclinal ridge (geology)". Britannica Online Encyclopedia. Retrieved 2008-03-16.
This landform occurs in areas of tilted strata and is caused by the differential weathering and erosion of the hard capping layer and the soft underlying cliff maker, which erodes more rapidly.
- ^ Divener, V. "Structural Control of Fluvial Landscapes". Crustal Structures and Landforms (course notes). Long Island University C.W. Post Campus. Retrieved 2008-03-16.
Homoclinal ridges formed by the resistant beds are typically asymmetrical (if the strata don't dip too steeply) with a steep scarp slope and a more gentle dip slope.