Continental Drift versus Plate Tectonics
How plates move The edges, or boundaries, of tectonic plates meet up in different ways. There are three main types of boundaries: transform, convergent, and divergent. At transform boundaries, plates move past each other. Earth's thin outer shell is broken into big pieces called tectonic plates. These plates fit together like a puzzle, but they're not stuck in one place. They are floating on Earth's mantle, a really thick layer of hot flowing rock. The flow of the mantle causes tectonic plates to move in different directions.
There are a few handfuls of major plates and dozens of smaller, or minor, plates. Six of the majors are named for the continents embedded within them, such as the North American, African, and Antarctic plates. Though smaller in size, the minors are no less important when it comes to shaping the Earth. The tiny Juan de Fuca plate is largely responsible for the volcanoes that dot the Pacific Northwest tectonic the United States.
How to get armpit stains out of shirts plates make up Earth's outer shell, called the lithosphere. This includes the crust tecronics uppermost part of the mantle. Churning currents in the molten rocks below propel them along like a jumble of conveyor belts in disrepair. Most geologic activity stems playe the interplay where the plates meet or divide.
The movement of the plates creates three types of tectonic movs convergent, where plates move into one another; divergent, where plates move apart; and transform, where plates move sideways in relation to each other. Where plates serving landmasses collide, the crust crumples and buckles into mountain ranges. India and Asia crashed about 55 million years ago, slowly giving rise to the Himalayathe highest mountain system on Earth. As the mash-up continues, the mountains get higher.
Mount Everest, the highest point on Earth, may be a tiny bit taller tomorrow than it is today. These convergent boundaries also occur where a plate of ocean dives, in a process called subduction, under a fectonics. As the overlying plate lifts up, it also forms mountain ranges.
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. At 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.
These types of collisions can also lead to underwater volcanoes that eventually build up into island arcs like Japan. At divergent boundaries in the oceans, magma from deep in the Earth's mantle rises toward the surface and pushes apart two or more plates.
Mountains and volcanoes rise along the seam. The process renews the ocean floor and widens the giant basins. A single mid-ocean ridge system connects the world's oceans, making the ridge the longest mountain range in the world.
On land, giant troughs such as the Great Rift Valley in Africa form where plates are tugged apart. If the plates there continue to diverge, millions of years from now eastern Africa will split from the continent to form a new landmass.
A mid-ocean ridge would then mark the boundary between the plates. The San Andreas Fault in California is an example of a transform boundary, where two plates grind past each other along what are called strike-slip faults. These boundaries don't produce spectacular features like mountains or oceans, but the halting motion often triggers large earthquakes, such as the one that devastated San Francisco.
All rights reserved. Lava spews out of a fissure in the Virunga mountains in the Democratic Republic of the Congo. The Virunga chain is part of the East African Rift Valley system, which marks the boundary between two plates: the Nubian plate to the west and the Somalian plate to the east.
The rift valley is a classic example of a divergent plate boundary. They move at a rate of one etctonics two inches three to five centimeters per jove. Convergent Boundaries Where plates serving landmasses tectonis, the crust crumples and buckles into mountain ranges. Divergent Tectoincs At divergent boundaries in the oceans, magma from deep in the Earth's mantle rises toward the surface and pushes apart two or more plates.
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Jan 18, · They move at a rate of one to two inches (three to five centimeters) per year. Convergent Boundaries Where plates serving landmasses collide, the . Mar 21, · The theory of plate tectonics states that the Earth’s solid outer crust, the lithosphere, is separated into plates that move over the asthenosphere, the molten upper portion of the mantle. Oceanic and continental plates come together, spread apart, and interact at boundaries all over the planet. Apr 09, · The concept of plate tectonics was formulated in the s. According to the theory, Earth has a rigid outer layer, known as the lithosphere, which is typically about km (60 miles) thick and overlies a plastic (moldable, partially molten) layer called the chesapeakecharge.com lithosphere is broken up into seven very large continental- and ocean-sized plates, six or seven medium-sized .
At transform boundaries, plates move past each other. This is one of the most common causes of earthquakes. At convergent boundaries, plates move toward each other.
They can push together and cause mountain ranges to form. At other times, one plate gets pushed down beneath the other plate. This can cause volcanoes. At divergent boundaries, plates move apart from each other.
When this happens, new plate material forms. Two plates pushed together create a convergent fault. If one plate is oceanic and the other continental, the edge of the oceanic plate will be pushed down.
Oceanic plate. Continental plate. When two plates move past each other, they create a transform fault. The movement is jerky, and can cause earthquakes. Moving plate. When two plates move away from each other they create a divergent boundary. When this happens under oceans, new ocean floor is created. Convergent Two plates pushed together create a convergent fault. Transform When two plates move past each other, they create a transform fault.
Divergent When two plates move away from each other they create a divergent boundary.