(Geomorphology)
From the Italian for "incline", a cuesta is a landform
that develops where the local geology consists of gently tilted (formerly
horizontal) layers of sedimentary rock. Sedimentary layers
that have been more severely tilted form hogback ridges rather than cuestas.
Multiple beds of sedimentary rock invariably contain layers more resistant
to erosion than others; these layers, of course form the high points,
and protect the rock underneath. When the layers are more or less gently
tilted, the resistant layers support long ridges, each with has a steep
escarpment on one side, and a gentle slope on the other. Between
the ridges, less-resistant rock erodes away to form broad valleys.
A cross-section of a cuesta landscape might look like this:
_
_ {_`-._ _
{_`-._ } `-._`-._ {_`-._
} `-._`-._~~~~~~. ," `-._`-._~~~~~. } `-._`-._
.~" `-._`-._ `~~~~~~_~~~~"-._ `-._`-._ `~~~~~~~. ,"`-._ `-._`-._~~~~~~.
~~~" `-._`-._ `-._ `-._ `-._`-._ `~~~~~~__~~~~~~~"`-._ `-._ `-._`-._ `~~~._
Cuestas are invariably eroded by the antecedent drainage systems
in place when the landscape began to be uplifted. As the landscape
develops, its underlying geology shapes the drainage into a distinctive
trellised drainage form. An aerial view of a cuesta landscape can be
seen in the trellised drainage node.
As the landscape develops, and subsequent streams excavate the valleys,
consequent and would-be consequent streams carve gaps in the ridges.
The cuestas are separated into segments resembling long lines of lemon
wedges. As the valleys will continue to be excavated, the resistant
layers at the tips of the escarpments are undermined and break off.
The tips of the resistant layers migrate across the landscape. As
long as there is continued uplift (or sea level drop),
the valleys will migrate with them. Eventually, however, the ridges
will be worn away into nothing.
Cuestas also form around the fringes of large mountain ranges, where
horizontal sedimentary layers have been distorted by a nearby area of tectonic
uplift.
Cuestas can be found all over the world. Some examples include:
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The central Arabian Peninsula, around Riyadh, Saudi Arabia.
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The Atlantic Coastal Plain area in central New Jersey (south of New
Jersey, rock layers are more or less flat)
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The entire northeastern Midwest United States (Wisconsin, Illinois,
Iowa, Michigan, Indiana, Ohio, and western New York), and into
southern Ontario, through which the Niagara Escarpment winds.
The Middle Plateau at the bottom of Lake Michigan is a cuesta.
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North Mountain in Nova Scotia.
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Areas of the Colorado Plateau in the Southwestern US.
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The North Downs and South Downs in Kent and Sussex, England.
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The Black Range in Victoria, Australia.
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The Stepped Hills of Tasmania.
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The foothills of the Swabian Alps.
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The ridge upon which parts of Hadrian's Wall was built.
If I missed your favorite cuesta, let me know.