9781422269534

The Himalaya-Karakoram mountain range is the world’s greatest mountain range on land. It contains 96 of the world’s 109 peaks over 24,000 feet (7,315 m). Amazing! The longest land mountain range in the world is the Andes Mountain Range in South America. It stretches 4,700 miles (7,564 km) in length. However, the world’s longest mountain range is underwater. The Mid-Ocean Ridge stretches from the Arctic Ocean to the Atlantic Ocean. It is 40,000 miles long (64,374 km) and goes around Asia, Australia, and Africa, under the Pacific Ocean, and extends to the North American West Coast. Even more amazing! Divergent boundaries occur when two tectonic plates move away from each other. As the plates separate, magma rises to fill the gap, creating new crust. The movement and interaction of these plates can result in earthquakes, although they are generally less severe than those at convergent boundaries. The Mid-Atlantic Ridge is an example of a divergent boundary, which are also called normal faults because they create space between tectonic plates. Two examples are North America’s Basin and Range Province and the East African Rift Zone. Transform boundaries occur when two tectonic plates slide past each other horizontally. There is very little vertical movement. As the plates become interlocked, stress builds up due to friction along the fault line. When the stress overcomes the friction, the plates suddenly slip, releasing energy and causing an earthquake. These are also known as strike-slip faults. The San Andreas Fault in California is a well-known example of a transform boundary, as are the Anatolian Faults that ruptured during the February 2023 earthquake in Turkey. Transform boundaries are also called strike-slip faults.

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What Makes an Earthquake