rift valley


Also found in: Dictionary, Thesaurus, Medical, Wikipedia.
Related to rift valley: Rift Valley fever, Great Rift Valley

rift valley,

elongated depression, trough, or graben in the earth's crust, bounded on both sides by normal faults and occurring on the continents or under the oceans. The central flat block forming the trough slips downward relative to the crustal blocks on either side. The appearance is that of a fallen keystone in a broken arch. Rift valleys form by tensional forces, typically those associated with the initiation of plate separation (see plate tectonicsplate tectonics,
theory that unifies many of the features and characteristics of continental drift and seafloor spreading into a coherent model and has revolutionized geologists' understanding of continents, ocean basins, mountains, and earth history.
..... Click the link for more information.
). The development of a rift valley in a continent is believed to be a precursor to the breakup of the continent and the development of a new ocean basin by seafloor spreadingseafloor spreading,
theory of lithospheric evolution that holds that the ocean floors are spreading outward from vast underwater ridges. First proposed in the early 1960s by the American geologist Harry H.
..... Click the link for more information.
. Rift valleys, such as the Red Sea and the African rift valleys (see Great Rift ValleyGreat Rift Valley,
geological fault system of SW Asia and E Africa. It extends c.3,000 mi (4,830 km) from N Syria to central Mozambique. The northernmost extension runs S through Syria and Lebanon, the Jordan valley, the Dead Sea, and the Gulf of Aqaba.
..... Click the link for more information.
), are commonly the sites of volcanism and the locus of much earthquake activity.
The Columbia Electronic Encyclopedia™ Copyright © 2013, Columbia University Press. Licensed from Columbia University Press. All rights reserved. www.cc.columbia.edu/cu/cup/

rift valley

[′rift ‚val·ē]
(geology)
A deep, central cleft with a mountainous floor in the crest of a midoceanic ridge. Also known as central valley; midocean rift.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

rift valley

a long narrow valley resulting from the subsidence of land between two parallel faults, often associated with volcanism. The East African Rift Valley is an example
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
References in periodicals archive ?
Mr Buzeki said CCM will champion unity in the Rift Valley and warned a section of Jubilee politicians attempting to divide residents along tribal lines.
Complete genome analysis of 33 ecologically and biologically diverse Rift Valley fever virus strains reveals widespread virus movement and low genetic diversity due to recent common ancestry.
Kenya has already developed 190 MW of geothermal power through a 1980s World Bank-financed project at the Rift Valley site of Olkaria, and last year obtained financing to expand its capacity by an additional 280 MW.
"If you stripped away all of the ice here today, you'd see a feature every bit as dramatic as the huge rift valleys you see in Africa and in size as significant as the Grand Canyon.
Africa Railways is the largest shareholder in Rift Valley Railways and has management rights.
Prevalence of Rift Valley fever immunoglobulin G antibody in various occupational groups before the 2007 outbreak in Tanzania.
Julia Murugi, a local resident who was gang raped after the 2007 election, has taken her seven children out of their Rift Valley home in Nyakinyua and is staying with relatives 300km away.
The project was set up as a link between the Newcastle Law Society and the Rift Valley Law Society in Kenya and has benefited more than 3,000 children and parents as they provide legal advice, assistance and representation.
Working in Kenya's geologically active Rift Valley, where high subterranean temperatures are close to the surface, the consortium uncovered wells of steam able to generate 4-5 MegaWatts (MW) of electricity and one yielding 8MW.
The temporary measure, which will last until further notice, is a precautionary move following outbreak of bird flu in South Africa and Rift Valley Fever in Madagascar .
The movement created the valley that is known today as the Great Rift Valley. This valley is very rich in fossils but it is famous for the discovery of the bones of an early human who lived there 3 million years ago.
The highest drop in production was in regions west of the Rift Valley, where production fell by 50%, from 62 million kg registered during the same period last year to 31 million kg.