Cuestra
- a scarp foot
- b escarpment
- c dip slope
- d back slope
- e resistant rock layer
- f easily eroded layer
A cuestra is a ridge formed where gently tilted rock layers which
are more resistant to erosion
than the surrounding layers intersect
the earth's surface. Cuestras have a steep slope (the escarpment, b)
and a gentle, or dip, slope, c. On either side of the cuestra lies
lower land where erosion has carried away more of the softer layers.
Cuestras differ from hogbacks in that the resistant rock layers
forming the hogback intersect the surface at much steeper angles,
creating steep slopes on both sides of the intrusion.
Cuestras and hogbacks abound in the southwest.
References
- Basin and Range, John McPhee, Noonday Press.
- The Colorado Plateau : A Geologic History, Donald L. Baars, Univ of New Mexico Press.
- Navajo Country : A Geology and Natural History of the Four Corners Region, Donald Baars, Univ. New Mexico Press.
- Roadside Geology of Arizona, Halka Chronic, Mountain Press.
After The Field Guide to Geology, David Lambert and the
Diagram Group, Facts-on-File
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