![]() According to the world Atlas, there are nine major plates around the earth.These plates have been named after the landforms which were found on them.Therefore the names of the plates are: North American, Eurasian,African, Indo-Australian,Australian,Indian,South American and Antarctic. This theory was developed from the 1950's through 1970’s. Note: The continental drift theory was first proposed by Alfred Wegener. The outer layer is known as lithosphere which has a thickness of 100 km. Tectonic Plate theory is a scientific explanation that the outer covering of the earth is divided into several plates which slide over the mantle, which is the rocky inner layer above the core. When a divergent boundary takes place beneath the lithosphere,the convection current underneath it rises,which lifts the lithosphere,creating a mid oceanic ridge. Divergent boundaries often give rise to volcanic islands. The oceanic plates and mid-oceanic ridges are the most common places for a divergent boundary to occur. A mid-ocean ridge would then mark the boundary between the plates.Hint:Earthquakes are common in divergent boundaries and mantle is seen rising from the earth’s mantle to the surface which solidifies to create a new oceanic crust.Ĭomplete answer: Divergent boundary is a linear feature in the theory of plate tectonics that takes place between two tectonic plates when they pull away from each other.This occurs due to the rise in convection currents.When a divergent boundary occurs in the continents,it creates a rift and later on creates a rift valley. If the plates there continue to diverge, millions of years from now eastern Africa will split from the continent to form a new landmass. On land, giant troughs such as the Great Rift Valley in Africa form where plates are tugged apart. A single mid-ocean ridge system connects the world's oceans, making the ridge the longest mountain range in the world. The process renews the ocean floor and widens the giant basins. Mountains and volcanoes rise along the seam. Divergent BoundariesĪt divergent boundaries in the oceans, magma from deep in the Earth's mantle rises toward the surface and pushes apart two or more plates. An example of this is the Mid-Atlantic Ridge, where magma rises from. In the western part of the continent, divergent plate boundary forces are beginning to rip the continent apart, forming the Basin and Range Province and its adjacent eastern arm, known as the Rio Grande Rift. These types of collisions can also lead to underwater volcanoes that eventually build up into island arcs like Japan. Divergent boundaries: In such a boundary two plates are moving away from each other. In addition, the diving plate melts and is often spewed out in volcanic eruptions such as those that formed some of the mountains in the Andes of South America.Īt ocean-ocean convergences, one plate usually dives beneath the other, forming deep trenches like the Mariana Trench in the North Pacific Ocean, the deepest point on Earth. As the overlying plate lifts up, it also forms mountain ranges. These convergent boundaries also occur where a plate of ocean dives, in a process called subduction, under a landmass. Mount Everest, the highest point on Earth, may be a tiny bit taller tomorrow than it is today. As the mash-up continues, the mountains get higher. India and Asia crashed about 55 million years ago, slowly giving rise to the Himalaya, the highest mountain system on Earth. ![]() Where plates serving landmasses collide, the crust crumples and buckles into mountain ranges. They move at a rate of one to two inches (three to five centimeters) per year. The movement of the plates creates three types of tectonic boundaries: convergent, where plates move into one another divergent, where plates move apart and transform, where plates move sideways in relation to each other. Most geologic activity stems from the interplay where the plates meet or divide. ![]() (This includes the crust and uppermost part of the mantle.) Churning currents in the molten rocks below propel them along like a jumble of conveyor belts in disrepair. ![]() The plates make up Earth's outer shell, called the lithosphere. The tiny Juan de Fuca plate is largely responsible for the volcanoes that dot the Pacific Northwest of the United States. Though smaller in size, the minors are no less important when it comes to shaping the Earth. Six of the majors are named for the continents embedded within them, such as the North American, African, and Antarctic plates. There are a few handfuls of major plates and dozens of smaller, or minor, plates.
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