According to the U.S. Geological Survey website, tectonic plates are massive, irregular-shaped slabs of solid rock, composed of oceanic and continental lithosphere. The continental crust is made up of lightweight minerals like feldspar and quartz, while the oceanic crust is made of heavier and denser basaltic rocks.
The sizes of these plates vary greatly. The Antarctic and Pacific Plates have been recorded as some of the largest. The boundaries between tectonic plates are usually unseen as they lie beneath the ocean. However, the boundaries for oceanic plates are mapped out accurately by measurements known as GEOSAT satellites. Volcanic activity and earthquakes occur close to these boundaries.Learn More
Continental and oceanic are the two types of tectonic plates. Continental plates tend to be larger than oceanic and bear the majority of a continent's mass. Continental plates tend to be much thicker on average, but less dense.Full Answer >
Earth has between 10 and 20 crustal plates, each moving at a different rate. The slowest is the Eurasian plate, which moves less than an inch per year, while the plate with fastest known movement is the Cocos plate, which grinds against the west coast of Central America at an estimated 8.55 inches per year.Full Answer >
Earth's tectonic plates move due to the movement of magma in the mantle underneath the crust. Extreme temperatures inside the planet's core cause a convection cycle in which hot magma rises to the surface and eventually sinks back toward the core as it cools.Full Answer >
Tectonic plates move at the rate of about 1 to 2 inches each year. Tectonic plates can move in various directions, causing them to collide at certain points on Earth and pull away at other points.Full Answer >