When two continental plates collide neither plate can be subducted due to their high bouyancy. With this type of collision there are no features such as a subduction zone, trench or acretionary wedge. After collision the oceanic lithosphere breaks off and sinks into the mantle.

Lithospheric plates are part of a planetary scale thermal convection system. The energy source for plate tectonics is Earth’s internal heat while the forces moving the plates are the “ridge push” and “slab pull” gravity forces. It was once thought that mantle convection could drive plate motions.

If two tectonic plates collide, they form a convergent plate boundary. Usually, one of the converging plates will move beneath the other, a process known as subduction.

The heat from radioactive processes within the planet’s interior causes the plates to move, sometimes toward and sometimes away from each other. This movement is called plate motion, or tectonic shift.

What happens when two continental plates collide? Instead, a collision between two continental plates crunches and folds the rock at the boundary, lifting it up and leading to the formation of mountains and mountain ranges.

Oceanic plates are much thinner than the continental plates. At the convergent boundaries the continental plates are pushed upward and gain thickness. The rocks and geological layers are much older on continental plates than in the oceanic plates. The Continental plates are much less dense than the Oceanic plates.

An example of an oceanic plate is the Pacific Plate, which extends from the East Pacific Rise to the deep-sea trenches bordering the western part of the Pacific basin. A continental plate is exemplified by the North American Plate, which includes North America as well as the oceanic crust…

The Nazca plate is an oceanic tectonic plate in the southeastern Pacific Ocean that shares both convergent and divergent boundaries, corners multiple triple junctions, contains three seamount chains, overrides four hotspots, and is responsible for the creation of the Andean orogeny (Figure 1).

Because of their heavy ferromagnesian elements, oceanic plates are much denser than continental plates. The average density of ocean plates is approximately 200 pounds per cubic foot, while continental crust ranges between about 162 and and 172 pounds per cubic foot.

Plates are on average 125km thick, reaching maximum thickness below mountain ranges. Oceanic plates (50-100km) are thinner than the continental plates (up to 200km) and even thinner at the ocean ridges where the temperatures are higher.

Continental crust has a lower density due to a higher content of lighter silicates compared to ocean crust – which makes oceanic plates heavier than continental plates.

When two plates carrying oceanic crust collide, the plate carrying older oceanic crust will be forced below the other in a process called subduction….

When two plate move towards each other they converge or come together. The collision between two plates that are moving towards each other is called a convergent boundary. The collision results in large damaging earthquakes. When two continental plates converge the result is the formation of large folded mountains.

Are They Dangerous Places to Live? Mountains, earthquakes, and volcanoes form where plates collide. If we choose to live near convergent plate boundaries, we can build buildings that can resist earthquakes, and we can evacuate areas around volcanoes when they threaten to erupt.

When oceanic or continental plates slide past each other in opposite directions, or move in the same direction but at different speeds, a transform fault boundary is formed. No new crust is created or subducted, and no volcanoes form, but earthquakes occur along the fault.

In this lesson, we explore the causes of plate movement, including thermal convection, ridge push and slab pull.

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. They move at a rate of one to two inches (three to five centimeters) per year.

There are four types of boundaries between tectonic plates that are defined by the movement of the plates: divergent and convergent boundaries, transform fault boundaries, and plate boundary zones.

Tectonic plates are pieces of Earth’s crust and uppermost mantle, together referred to as the lithosphere. The plates are around 100 km (62 mi) thick and consist of two principal types of material: oceanic crust (also called sima from silicon and magnesium) and continental crust (sial from silicon and aluminium).

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Three-dimensional diagram showing crustal generation and destruction according to the theory of plate tectonics; included are the three kinds of plate boundaries—divergent, convergent (or collision), and strike-slip (or transform).

Why do plates move? One explanation for plate movements is slab pull. Plates are extremely heavy so gravity acts upon them, pulling them apart. Alternatively, as shown in the diagram, convection currents under the Earth’s crust transfer heat, which rises through the surface and cools back down in a circular motion.

Scientists believe that Pangea broke apart for the same reason that the plates are moving today. The movement is caused by the convection currents that roll over in the upper zone of the mantle. About 200 million years ago Pangaea broke into two new continents Laurasia and Gondwanaland.

Plate tectonics affects humans in several important ways. What would Earth be like without plate tectonics? We’d have many fewer earthquakes and much less volcanism, fewer mountains, and probably no deep-sea trenches. In other words, the Earth would be a much different place.

If all plate motion stopped, Earth would be a very different place. Erosion would continue to wear the mountains down, but with no tectonic activity to refresh them, over a few million years they would erode down to low rolling hills.

UNIVERSITY PARK, Pa. — There may be more habitable planets in the universe than we previously thought, according to Penn State geoscientists, who suggest that plate tectonics — long assumed to be a requirement for suitable conditions for life — are in fact not necessary.

Over millions of years, continents drift across Earth’s surface, going from one climate zone to another. Without plate tectonics, Earth would not have its diverse geography, which provides a wide range of habitats. Plate tectonics is also responsible for hydrothermal vents on the ocean floor.

If earth’s mountains were magically instantly removed, there would be immediate repercussions. All that stone has mass, and the crust beneath which had been pressed into the mantle would rebound, causing worldwide earthquakes. Volcanoes would erupt as their plugs of stone were removed or weakened.

At convergent plate boundaries, where two continental plates collide earthquakes are deep and also very powerful. In general, the deepest and the most powerful earthquakes occur at plate collision (or subduction) zones at convergent plate boundaries.

Dinosaurs lived on all of the continents. At the beginning of the age of dinosaurs (during the Triassic Period, about 230 million years ago), the continents were arranged together as a single supercontinent called Pangea. During the 165 million years of dinosaur existence this supercontinent slowly broke apart.