A rift valley refers to a narrow, elongated depression bordered by high-angle normal faults on both sides.
Famous rift valleys on Earth include the East African Rift Valley, the Rhine Rift Valley, and the Grand Canyon.
Today, we are going to introduce the world's largest rift valley—the East African Rift Valley.
The East African Rift Valley is located in eastern Africa. Its southern starting point is the lower Zambezi River valley, extending north through the Shire River valley and Lake Malawi.
Here, the rift splits into two branches. The eastern branch extends to the northern end of the Red Sea, with a length of about 5,800 kilometers.
The western branch passes through the world's second-largest lake, Lake Tanganyika, and ultimately reaches the White Nile valley in Sudan, with a total length of about 1,700 kilometers.
Formation of the East African Rift Valley
The East African Rift Valley is located at the boundary between the African Plate and the Indian Ocean Plate. These two plates move in opposite directions, creating the current East African Rift Valley.
Its formation began about 30 million years ago.
Southeast of the eastern branch of the East African Rift Valley stands Africa's highest peak, Mount Kilimanjaro, with an elevation of 5,895 meters.
Nearby is Mount Kenya, with an elevation of 5,199 meters.
The formation of Mount Kilimanjaro is primarily due to the crustal rifting and intense volcanic activity of the East African Rift, with lava continuously accumulating.
Despite being near the equator, the summit temperature of Kilimanjaro is below freezing year-round due to its nearly 6,000-meter elevation, and it is perpetually snow-covered, earning it the nickname "Equatorial Snow Peak."
"Products" of the East African Rift Valley
The formation of the East African Rift Valley has created 30 large lakes on the African continent, including Lake Tanganyika, Lake Malawi, Lake Kivu, and Lake Mobutu.
These lakes are all very large.
Lake Tanganyika
Lake Tanganyika, located in the western branch of the East African Rift Valley, is the world's largest rift lake, with a length of about 679 kilometers from north to south and a width of about 50 kilometers from east to west. The total shoreline length is nearly 1,900 kilometers.
Lake Tanganyika covers an area of 32,900 square kilometers, ranking sixth in the world. Its average depth is 570 meters, with a maximum depth of 1,470 meters, making it the second deepest lake in the world after Lake Baikal.
The lake's water volume reaches 18,900 cubic kilometers, also second only to Lake Baikal's 23,600 cubic kilometers.
Lake Malawi
Lake Malawi is located at the southern end of the East African Rift Valley and is the third-largest lake in Africa, following Lake Tanganyika and Lake Victoria.
Lake Malawi is about 584 kilometers long from north to south, with a maximum width of nearly 80 kilometers from east to west, covering an area of nearly 30,000 square kilometers.
Due to its location in the East African Rift Valley, its maximum depth reaches 704 meters. Although not as deep as Lake Tanganyika's 1,470 meters, it is still one of the deepest lakes globally, ranking sixth.
The Future of the East African Rift Valley
The East African Rift Valley is located at a plate boundary where two plates are diverging. In the future, the width of the East African Rift Valley will continue to increase, possibly forming a sea similar to the Red Sea.
Over time, the part of the African continent east of the East African Rift Valley may become an independent continental plate, but this will take tens of millions or even hundreds of millions of years.
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