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ECOSYSTEMS > INLAND OREGON > VALLEYS
A rift valley forms at areas where Earth's tectonic plates are moving apart, forming a lowland (or rift) between them. Because of this tectonic movement, they are sometimes referred to as "pull-apart valleys." Earthquakes and geothermal activity are not uncommon in these types of valleys. The Jordan Rift Valley where the Dead Sea is located between Israel and Jordan (see photo above) is one of the best known rift valleys. However, one of the largest valleys is the Great Rift Valley located in eastern Africa. This complex of geological features covers a combined area of over 3,000 square miles (4,828 square km) from the Red Sea to the Horn of Africa. The Salton Trough (which includes both the Coachella and Imperial Valleys) is a good example of a rift in the western United States. It formed between the north moving Pacific Plate and the south moving North American plate and is part of the larger San Andreas fault system. The Salton Sea (see photo to the left) is located in the center of this rift. Rift valleys are also found on the ocean floor where tectonic movement is more obvious. There are no rift valleys in Oregon. |