You probably understand by now that the inside of Earth is anything but still. You're about to find out how layers of rock collide, slide, and pull apart in a geologic dance that creates the landscapes we call home.
Watch this animation to find out more about how the movement of tectonic plates causes geologic events and shapes landforms. Then answer the questions in the Take Notes box below.
Before you watch, you might want to check the definitions of specific vocabulary terms. In addition to geosphere, the terms asthenosphere, convection currents, lithosphere, earthquakes, magma, and volcanoes will be defined, and tectonic plates and their movement will be described.. You may pause the animation, rewatch it as many times as you like, and read the transcript.
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Our geosphere - the rock portion of our planet - is made up of layers that quite literally move the Earth under our feet.
The rigid upper portion of our geosphere is called the lithosphere (crust + upper mantle) which is separated into different plates of various sizes, thickness and densities. Below these lithospheric plates is a section of gooey, hot mantle called the asthenosphere.
Powered by the core’s heat, the asthenosphere warms, rises, cools, and sinks again (aka convection currents). And as it does, it moves the plates above it - they collide, slide and pull apart, and the lithosphere is created and destroyed in some geologically awe-inspiring ways.
Where plates collide, mountains form, volcanoes erupt, the crust melts back into the mantle, and earthquakes occur.
When plates slide past each other, we get earthquakes.
And as plates get pulled apart, liquid rock (magma) rises to create new earth (volcanoes) and yes–more earthquakes.
All this is happening slowly. But even at a rate of centimeters per year, these plate boundaries are the scene of some pretty epic earth-making.
Type the answer to these questions in the Notes Box, below:
1. What is the rigid, upper portion of the geosphere called?
3. What are three ways tectonic plates move?