The asthenosphere is a soft, partially molten layer of the upper mantle, located beneath the lithosphere. It is characterized by its ductility, meaning it can flow and deform under pressure. This plasticity is crucial for plate tectonics, as it allows the lithospheric plates to move and interact with each other.

While the asthenosphere is not entirely liquid, it contains pockets of molten rock called magma. These pockets can rise to the surface, causing volcanic eruptions.

Here's a breakdown:

* Lithosphere: The rigid outer layer of Earth, consisting of the crust and the uppermost part of the mantle.

* Asthenosphere: The partially molten layer beneath the lithosphere, characterized by its ductility.

* Magma: Molten rock found beneath the Earth's surface.

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