The rifting of Iceland The Mid-Atlantic Ridge passes through Iceland, where the island is splitting in two different areas (see FIGURE3 ). This can be seen where Iceland’s volcanoes are located, at the point where the North American Plate is drifting to the west and the Eurasian Plate is drifting to the east (see FIGURE4 ). New crust is being formed in a rift below the sea, and eventually water from the Atlantic Ocean will fill the widening and deepening gaps between the separated parcels of land.
FIGURE4 A volcanic fissure in Iceland
The Great Rift Valley, Africa The Great Rift Valley is in Africa (see FIGURE5 ) is about 5000 kilometres long, and stretches from Syria in the north to Mozambique in the south. The valley varies in width from 30 kilometres at its narrowest point to 100 kilometres at its widest. In some places it is a few hundred metres deep; in others it can be a few thousand metres deep. The Great Rift Valley was created through separation that began 35 million years ago, when the African and Arabian plates began pulling apart in the northern region. About 15 million years ago, east Africa began to separate from the rest of Africa along the East African Rift. The volcanic activity in this region has produced many volcanic mountains, such as Mount Kilimanjaro, Mount Kenya and Mount Elgon. As these rifts continue to grow, new ocean waters will flow into the valleys, separating the landmasses.
396 Jacaranda Humanities Alive 8 Victorian Curriculum Third Edition
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