Rift

This article does not cite any references or sources. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (November 2007)

This article may need to be rewritten entirely to comply with Wikipedia's quality standards. You can help. The discussion page may contain suggestions. (May 2009)

USGS image

Plates in the crust of the earth, according to the plate tectonics theory

In geology, a rift is a place where the Earth's crust and lithosphere are being pulled apart^[1] and is an example of extensional tectonics.^[2]

Typical rift features are a central linear downdropped fault segment, called a graben, with parallel normal faulting and rift-flank uplifts on either side forming a rift valley, where the rift remains above sea level. The axis of the rift area commonly contains volcanic rocks and active volcanism is a part of many, but not all active rift systems.

Most rifts occur along the central axis of a mid-ocean ridge, where new oceanic crust and lithosphere is created along a divergent boundary between two tectonic plates.

Failed rifts are where continental rifting began, but then failed to continue to the point of break-up. Typically the transition from rifting to spreading develops at a triple junction where three converging rifts meet over a hotspot. Two of these evolve to the point of seafloor spreading, while the third ultimately fails, becoming an aulacogen.

Examples

• The East African Rift
• The Red Sea Rift
• The Baikal Rift Zone, the bottom of Lake Baikal is the deepest continental rift on the earth.
• The Gulf of Suez Rift
• Lake Timiskaming in Temiskaming Shores, Ontario
• Throughout the Basin and Range Province in North America
• The Rio Grande Rift in the southwestern US
• The rift zone that contains the Gulf of Corinth in Greece
• The Reelfoot Rift, an ancient buried failed rift underlying the New Madrid Seismic Zone in the Mississippi embayment
• The Rhine Rift, in south western Germany, known as the Upper Rhine valley
• The Taupo Volcanic Zone in the north east North Island of New Zealand
• The Oslo Graben in Norway
• The Ottawa-Bonnechere Graben in Ontario and Quebec
• The Northern Cordilleran Volcanic Province in British Columbia, Yukon and Alaska
• The West Antarctic Rift in Antarctica
• The Midcontinent Rift System, a late Precambrian rift in central North America
• The Fundy Basin, a Triassic rift basin in southeastern Canada

References

Wikimedia Commons has media related to: Rift