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非洲东部有一个著名的地理奇观,这就是东非大裂谷。它处于非洲最高的地带,总面积500多万平方千米,占非洲面积的1/6左右。有人形象地把它叫作“地球表皮上的一条大伤痕”。那么,东非大裂谷是怎么形成的呢?板块构造学说认为,地壳的断裂作用形成了这一巨大的陷落带。裂谷带是陆地板块分离的地方,非洲东部正好处于地幔物质上升运动强烈的地带。在上升流的作用下,东非地壳抬升形成高原,上升流向两侧相反方向的分散作用使地壳脆弱部
There is a famous geographical wonders in eastern Africa, which is the Great Rift Valley in East Africa. It is in the highest zone in Africa, with a total area of more than 5 million square kilometers, accounting for about 1/6 of the African area. Someone vividly called it “a big scar on the epidermis of the earth.” So, how is the Great Rift Valley formed? Plate tectonics theory that the fracture of the crust formed this huge fall belt. The rift zone is where the land plate separates, and the eastern part of Africa is exactly where the mantle material is rising strongly. Under the action of upwelling, the crust in East Africa uplifted to form a plateau. The dispersion of the upwelling direction in opposite directions made the crust vulnerable