Get Chapter 8 - Plate Tectonics - Quiz Questions 1- 6

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 made plate tectonics a dominant process only on Earth? How did the planet cool down before plate tectonics? Was the Earth's crust formed during the early stages of its evolution or is it the result of a gradual distillation of the mantle that continues today along with crustal recycling?

Researchers from Yale University said that tectonic plates beneath the Earth's surface, which normally shift over the course of tens to hundreds of millions of years, sometimes move abruptly.

And the rate at which a plate sinks depends mostly on its age/temperature/density: older plates are cooler/denser, thus they sink at a higher velocity than younger plates. Save this answer.

The Pacific Plate is the fastest at over 10 cm/year in some areas, followed by the Australian and Nazca Plates. The North American Plate is one of the slowest, averaging around 1 cm/year in the south up to almost 4 cm/year in the north.

What happens at divergent plate boundaries in the continental crust? What are the moving plates of the Earth's crust called? Is the continental crust heavier than the oceanic crust? How does the mantle affect the Earth's crust?

Even though plates move very slowly, their motion, called plate tectonics , has a huge impact on our planet. Plate tectonics form the oceans, continents, and mountains. It also helps us understand why and where events like earthquakes occur and volcanoes erupt.

Most plates move less than a millimeter per day; this movement is imperceptible to human senses. However, this daily motion translates to 1-10 centimeters of movement over a year, and that yearly motion translates to 10-50 kilometers of movement over a million years.

convection currents are a process in which the materials inside the mantle heat up and rise to the surface whilst the cooler liquid sinks; as it sinks it then heats up and rises again. This continuous cycle is established: hot liquid rising, cold liquid descending. These currents cause the tectonic plates to move.