What is plate tectonics?
Plate tectonics is the theory that Earth’s outer shell is divided into several plates that glide over the mantle, the rocky inner layer above the core. The plates act like a hard and rigid shell compared to Earth’s mantle.
What causes tectonic plates to float around the Earth?
This slow but incessant movement in the mantle causes the rigid tectonic plates to move (float) around the earth surface (at an equally slow rate). What happens at tectonic plate boundaries?
What causes tectonic features on the Earth?
This plate motion causes them to collide, pull apart, or scrape against each other. Each type of interaction causes a characteristic set of Earth structures or “tectonic” features. The word, tectonic, refers to the deformation of the crust as a consequence of plate interaction.
How fast do tectonic plates move?
How fast do plates move? Typically ~50 mm/yr (2 in/year), but up to 240 mm/yr (10 in/yr). Geologic evidence shows that rates and directions change over time What is the geologic record of plate tectonics?
Plate tectonics is a scientific theory that explains how major landforms are created as a result of Earth’s subterranean movements. The theory, which solidified in the 1960s, transformed the earth sciences by explaining many phenomena, including mountain building events, volcanoes, and earthquakes.
How is the asthenosphere involved in plate tectonics?
Through convection, hot regions of the asthenosphere heated from below rise closer to the surface, propelling the plates, and displace colder, denser material, which sinks back to lower parts of the mantle.
How do plate tectonics build supercontinents?
For billions of years, plate tectonics built and fragmented supercontinents—land masses made of multiple continents merged together. The plate tectonic cycle begins with a supercontinent balanced by a super ocean.
How does drilling of the seafloor provide evidence for plate tectonics?
Drilling of the seafloor provides evidence for plate tectonics. The age of seafloor rocks varies systematicallywith distance from the mid ocean ridge. Rocks of the seafloor are young compared to most rocks on the continents