Page 94 - Science Course 2 (Book 2)
P. 94
Mo10-L3a: What is the Plate Tectonics Theory?
lithosphere
The Earth’s crust and uppermost part of the mantle
make up the lithosphere.
The lithosphere forms a rigid shell on the outside of
Earth which is broken into tectonic plates.
Scientists have identif ed 15 large tectonic plates.
The partially melted portion of the mantle below the
lithosphere is the asthenosphere. asthenosphere
The asthenosphere is hotter than the lithosphere and
can bend more easily.
SUMMARY
What is the Plate Tectonics Theory?
Earth’s lithosphere is broken into pieces called plates.
These plates move on Earth’s surface and interact in three different ways.
Ocean Crust Continental Crust
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