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An escarpment is a steep slope or long cliff that forms as a result of faulting or erosion and separates two relatively level areas having different elevations.
The terms scarp and scarp face are often used interchangeably with escarpment.[citation needed] Some sources differentiate the two terms, with escarpment referring to the margin between two landforms, and scarp referring to a cliff or a steep slope. In this usage an escarpment is a ridge which has a gentle slope on one side and a steep scarp on the other side.
More loosely, the term scarp also describes a zone between a coastal lowland and a continental plateau which shows a marked, abrupt change in elevation caused by coastal erosion at the base of the plateau.
Formation and description
Scarps are generally formed by one of two processes: either by differential erosion of sedimentary rocks, or by movement of the Earth's crust at a geologic fault. The first process is the more common type: the escarpment is a transition from one series of sedimentary rocks to another series of a different age and composition. Escarpments are also frequently formed by faults. When a fault displaces the ground surface so that one side is higher than the other, a fault scarp is created. This can occur in dip-slip faults, or when a strike-slip fault brings a piece of high ground adjacent to an area of lower ground.
Earth is not the only planet where escarpments occur. They are believed to occur on other planets when the crust contracts, as a result of cooling. On other Solar System bodies such as Mercury, Mars, and the Moon, the Latin term rupes is used for an escarpment.
Erosion
When sedimentary beds are tilted and exposed to the surface, erosion and weathering may occur. Escarpments erode gradually and over geological time. The mélange tendencies of escarpments results in varying contacts between a multitude of rock types. These different rock types weather at different speeds, according to Goldich dissolution series so different stages of deformation can often be seen in the layers where the escarpments have been exposed to the elements.
See also
- Cuesta – Hill or ridge with a gentle slope on one side and a steep slope on the other
- Fall line – Meeting point of uplands and coastal plain
- List of escarpments
References
- Easterbrook, Don J. (1999). Surface Processes and Landforms. Prentice Hall. ISBN 978-0-13-860958-0.[page needed]
- Summary: Escarpments, US Army Corps of Engineers.
- "Scarps and Terraces". Physiography. Radford University. Retrieved 24 December 2020.
This article needs additional citations for verification Please help improve this article by adding citations to reliable sources Unsourced material may be challenged and removed Find sources Escarpment news newspapers books scholar JSTOR July 2015 Learn how and when to remove this message An escarpment is a steep slope or long cliff that forms as a result of faulting or erosion and separates two relatively level areas having different elevations Escarpment face of a cuesta broken by a fault overlooking Trenton Cloudland Canyon State Park and Lookout Mountain in the U S state of Georgia The terms scarp and scarp face are often used interchangeably with escarpment citation needed Some sources differentiate the two terms with escarpment referring to the margin between two landforms and scarp referring to a cliff or a steep slope In this usage an escarpment is a ridge which has a gentle slope on one side and a steep scarp on the other side More loosely the term scarp also describes a zone between a coastal lowland and a continental plateau which shows a marked abrupt change in elevation caused by coastal erosion at the base of the plateau Formation and descriptionSchematic cross section of a cuesta dip slopes facing left and harder rocklayers in darker colors than softer ones Scarps are generally formed by one of two processes either by differential erosion of sedimentary rocks or by movement of the Earth s crust at a geologic fault The first process is the more common type the escarpment is a transition from one series of sedimentary rocks to another series of a different age and composition Escarpments are also frequently formed by faults When a fault displaces the ground surface so that one side is higher than the other a fault scarp is created This can occur in dip slip faults or when a strike slip fault brings a piece of high ground adjacent to an area of lower ground Earth is not the only planet where escarpments occur They are believed to occur on other planets when the crust contracts as a result of cooling On other Solar System bodies such as Mercury Mars and the Moon the Latin term rupes is used for an escarpment ErosionWhen sedimentary beds are tilted and exposed to the surface erosion and weathering may occur Escarpments erode gradually and over geological time The melange tendencies of escarpments results in varying contacts between a multitude of rock types These different rock types weather at different speeds according to Goldich dissolution series so different stages of deformation can often be seen in the layers where the escarpments have been exposed to the elements See alsoCuesta Hill or ridge with a gentle slope on one side and a steep slope on the other Fall line Meeting point of uplands and coastal plain List of escarpmentsReferencesEasterbrook Don J 1999 Surface Processes and Landforms Prentice Hall ISBN 978 0 13 860958 0 page needed Summary Escarpments US Army Corps of Engineers Scarps and Terraces Physiography Radford University Retrieved 24 December 2020
