Rift+Valley

Plate TectonicsRift Valley By: Ryan, Gary (moose) ,Nick,Crysta ,Sarah,and Josh One of the only rift valleys that exist on this planet is located in Africa. It is known as "The Great Rift Valley." It is a 6,000 foot fissure. It stretches from Mosambique to Lebanon, One of it's most dramatic sections slices right through Kenya splitting it into two halves.Elevations of the Great Rift Valley vary from 408 m (1,340 ft) below sea level at the shore of the Dead Sea to about 1,829 m (about 6,000 ft) above sea level at cliffs in Kenya. **(cotf.edu)**

What is a Rift Valley? A rift valley is a valley formed by the subsidence of a block of the Earth's crust between two or more parallel faults. They are long, deep valleys bounded by parallel faults. They form where Earth’s crust is being pulled apart. Rift valleys can appear on land or beneath bodies of water.**(encarta.msn.com PG 1)** Here is what a Rift Valley would look like. < The Great Rift Valley in Africa **(cache.virtualtourist.com)**

Well how did Rift Valleys form? One popular model for the EARS assumes that elevated heat flows from the mantle (strictly the asthenosphere) is causing a pair of thermal “bulges” in central Kenya and the Afar region of north-central Ethiopia. These bulges can be easily seen as elevated highlands on any topographic map of the area (Figure 1). As these bulges form, they stretch and fracture the outer brittle crust into a series of normal faults forming the classic horst and graben structure of **(geology.com/articles PG1)** [|rift valleys]**(homepage.mac.com PG1)<** Video Here **(geology.com/articles PG 1)** Well when did the Great Rift Valley Form? S ome 20 million years ago, the earth's crust weakened and tore itself apart creating a jagged rift, thousands of kilometers long, across the African continent. The land on either side erupted creating great volcanic mountains, while the valley floor gradually sank into a low flat plain. <This picture shows where the Great Rift Valley formed and where the plate boundries are. The picture below explains how rift valleys are formed**.(**[|**www.geocities.com**] **PG1)** What is the Rift Valley Fever? In the 1930s a disease broke out in Kenya known as Rift Valley Fever. The outbreaks broke out in irregular patterns but the disease showed up in Zimbabwe in 1999 after a great flood and in South Africa in 1999. This disease spread to many other continents later on and the Rift Valley Fever infested many places around the earth. The question was how did the disease leave the continent of Africa? The answer is thought to be that it leaves the continent being carried off by animals or insects that are shipped over the Red Sea of Jizan.
 * (**[|**www.tiscali.co.uk**] **PG1)**

Rift Valley Fever (RVF) is a viral zoonosis that primarily affects animals but also has the capacity to infect humans. Infection can cause severe disease in both animals and humans, leading to high rates of disease and death. The disease also results in significant economic losses due to death and abortion among RVF-infected livestock. **(www.fas.org PG1)** How do humans get RVF? Humans usually get RVF through bites from infected mosquitoes and possibly other biting insects that have virus-contaminated mouthparts. Humans can also get the disease if they are exposed to the blood, body fluids, or tissues of infected animals or species. Direct exposure to infected animals can occur during slaughter or through veterinary and obstetric procedures. Infection through aerosol transmission of RVF virus has occurred in the laboratory environment. Although the most common way a human gets RVF is through mosquito bites.The virus usually lies dormant in the eggs of Aedes mosquitoes. During heavy rains and floods, the eggs hatch large numbers of infected mosquitoes that feed on livestock and spread the virus. Other species of mosquitoes, and possibly other biting insects, can also become infected and spread the disease. The occurrence of disease in a large number of domestic animals is referred to as an "epizootic." The presence of a mosquito-borne epizootic can lead to an epidemic in humans. RVF is a viral disease and looks like this picture below:


 * (sumivector.com)**

·   Mild illness ·   Fever ·   Liver abnormalities ·   Hemorrhagic fever ·   Encephalitis ·   Ocular disease ·   Fever ·   Generalized weakness ·   Back pain ·   Dizziness ·   Extreme weight loss **(www.wrongdiagnosis.com PG1)**
 * Some ways to tell if you have Rift Valley Fever is if you have:**
 *  Shock
 *  Hemorrhage
 *  Headaches
 *  Coma
 * <span style="FONT-FAMILY: 'Cambria','serif'; mso-fareast-font-family: 'Times New Roman'; mso-bidi-font-family: Arial; mso-ascii-theme-font: major-latin; mso-hansi-theme-font: major-latin"> Seizures

<-- Rift valley fever is usually caused by large groups of mosquito Above this picture is where some of the RVF hit in afirca!
 * (www.globalsecurity.org PG1)**

Above is a picture of the areas affected by RVF in Madagascar! **How is RVF treated?** <span style="FONT-FAMILY: Arial, Helvetica, sans-serif"> Infected people usually get better in 2 days to 1 week after the start of the illness. Sometimes, however, the infection can cause severe bleeding, inflammation of the brain, or severe eye complications. There is no established course of treatment for patients infected with RVF virus. However, studies in monkeys and other animals have shown promise for ribavirin, an antiviral drug, for future use in humans. Additional studies suggest that interferon, immune modulators, and convalescent-phase plasma may also help in the treatment of patients with RVF.

** <span style="FONT-FAMILY: Arial, Helvetica, sans-serif">A person's chances of becoming infected can be reduced by taking measures to decrease contact with mosquitoes and other bloodsucking insects through the use of mosquito repellents and bednets. Avoiding exposure to blood or tissues of animals that may potentially be infected is an important protective measure for persons working with animals in RVF-endemic areas. <span style="FONT-FAMILY: Arial, Helvetica, sans-serif">** Who is at risk for RVF? ** The people that are at risk for RVF are people who sleep outdoors at night in areas where outbreaks occur.Other people such as animal herdsmen, slaughterhouse workers, veterinarians, and others who handle tissues of infected animals in areas where the virus is present are also at risk. International travelers who visit areas where the virus is present during periods when outbreaks or epidemics are occurring are at risk also. **(cdc.gov PG1)**
 * How is RVF prevented?

Work Cited Our main Search engine was the main/orginal of [|www.google.com] that is where we got most of our info pictures and sources from. http://www.dhpe.org/infect/rift.html http://www.tiscali.co.uk/reference/encyclopaedia/hutchinson/m0006339.html [|http://encarta.msn.com/media_701501799/Rift_Valley.html |[[http://encarta.msn.com/media_701501799/Rift_Valley.html|http://encarta.msn.com/media_701501799/Rift_Valley.html]]] http://encarta.msn.com/encyclopedia_761568078/Great_Rift_Valley.html#701501799 http://geology.com/articles/east-africa-rift.shtml http://www.jambokenya.com/jambo/location/rvalley.htm http://content.answers.com/main/content/wp/en/thumb/b/b8/300px-EAfrica.jpg <span style="FONT-FAMILY: 'Cambria','serif'; mso-fareast-font-family: 'Times New Roman'; mso-bidi-font-family: Arial; mso-ascii-theme-font: major-latin; mso-hansi-theme-font: major-latin">http://www.wrongdiagnosis.com/r/rift_valley_fever/symptoms.htm <span style="FONT-FAMILY: 'Cambria','serif'; mso-fareast-font-family: 'Times New Roman'; mso-bidi-font-family: Arial; mso-ascii-theme-font: major-latin; mso-hansi-theme-font: major-latin">http://www.fas.org/ahead/disease/rvf/outbreak/2000arabia.htm http://www.who.int/mediacentre/factsheets/fs207/en/ http://www.cdc.gov/ncidod/dvrd/spb/mnpages/dispages/rvf/rvf_qa.htm http://homepage.mac.com/hommocksearthscience/page7/files/page7_48.swf http://www.geocities.com/DaleEasley/Essays/RiftValley.gif