Graben
From Wikipedia, the free encyclopedia
- For other uses, see Graben (disambiguation).
A graben is a depressed block of land bordered by parallel faults.
A graben is the result of a block of land being downthrown producing a valley with a distinct scarp on each side. Grabens often occur side-by-side with horsts. Horst and graben structures are indicative of tensional forces and crustal stretching.
Graben are produced from parallel normal faults, where the hanging wall is downthrown and the footwall is upthrown. The faults typically dip toward the center of the graben from both sides. Horsts are parallel blocks that remain between grabens, the bounding faults of a horst typically dip away from the center line of the horst.
A single or multiple graben can produce a rift valley.
"Graben" is the German word for "ditch".
[edit] Famous grabens
- The Basin and Range region of the southwestern United States is an example of multiple horst/graben structures.
- The Rhine valley to the North of Basel, Switzerland
- The Oslo graben around Oslo, Norway
- Death Valley in California, United States
- The East African Rift Valley
- The Saguenay River Valley
- The Narmada River valley in central India
- The lower Godavari River valley in southern India
- Rima Ariadaeus on the Moon
[edit] See also
[edit] References
- McKnight, Tom L; Hess, Darrel (2000). “The Internal Processes: Graben”, Physical Geography: A Landscape Appreciation. Upper Saddle River, NJ: Prentice Hall, pp. 417. ISBN 0-13-020263-0.