Page 142 - Science Course 2 (Book 2)
P. 142
Mo11-L3a: Types of Plate Boundaries
Let’s Begin
The Plate Tectonics Theory
The theory of plate tectonics, proposed in the late 1960s, states that Earth’s surface is made of rigid
slabs of rock, or plates, that move with respect to each other.
Plate tectonics suggests that Earth’s surface is divided into large plates of rigid rock and each plate moves
over Earth’s hot and semi-plastic mantle.
Geologists use the word tectonic to describe the
Key Concept forces that shape Earth’s surface and the rock
Types of Plate Boundary structures that form as a result.
What is Plate Tectonics? The cold and rigid outermost rock layer of the Earth
is called the lithosphere.
The lithosphere is made up of the crust and the
solid, uppermost mantle.
lithosphere
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