What is tectonic plates, faults and crust? Explain in simple words.
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Earth has three main layers, just like an onion. At the center is the hot core, surrounded by the thick mantle, and finally the thin outer crust where we live. Think of it like an apple - the crust is as thin as the apple's skin compared to the whole fruit. This layered structure is important for understanding how our planet works.
Tectonic plates are massive pieces of Earth's crust that fit together like a giant jigsaw puzzle. These plates float on the hot, flowing mantle below and move very slowly - just a few centimeters each year. There are about 15 major plates covering the entire Earth's surface.
Faults are fractures or cracks in the Earth's crust where rocks have broken and moved. They form when the stress from moving tectonic plates becomes too much for the rocks to handle. Just like a cookie breaks when you bend it too far, rocks crack and create faults when they can't withstand the pressure.
The crust is Earth's outermost layer - incredibly thin compared to the planet's size. Imagine Earth as a basketball; the crust would be thinner than the ball's skin! There are two types: oceanic crust under the oceans is thinner, about 5-10 kilometers thick, while continental crust forming our land masses is thicker, ranging from 30 to 70 kilometers thick.
The crust is Earth's solid, rocky outer shell - the layer we live on. It's like the skin of an apple, very thin compared to the whole Earth. There are two types of crust. Oceanic crust is found under the oceans and is much thinner, only 5 to 10 kilometers thick. Continental crust forms our continents and is much thicker, ranging from 30 to 70 kilometers. Both types float on the hot, flowing mantle below.
The Earth's crust isn't one solid piece - it's broken into large sections called tectonic plates. Think of it like a cracked eggshell, where the pieces float on the liquid egg white underneath. These massive plates include the Pacific Plate, North American Plate, Eurasian Plate, and African Plate, among others. They move very slowly on the hot, flowing mantle below, just a few centimeters each year - about as fast as your fingernails grow!
Tectonic plates move because of convection currents in the hot mantle below. Just like when you heat soup on the stove, hot material in the mantle rises toward the surface while cooler material sinks back down. This creates circular flowing patterns called convection currents. These powerful currents act like conveyor belts, pushing and pulling the tectonic plates above them. The heat comes from Earth's incredibly hot core, which keeps the mantle flowing and the plates moving.
Faults are fractures in Earth's crust where rocks have broken and moved due to stress from tectonic plate movement. There are three main types of faults. Normal faults occur when rocks are pulled apart by tension, causing one block to drop down relative to the other. Reverse faults happen when rocks are pushed together by compression, forcing one block up over the other. Strike-slip faults occur when rocks slide horizontally past each other. When the stress becomes too great, rocks suddenly slip along these faults, releasing energy and causing earthquakes.