The solid outer part of the Earth, elongating to a depth of about 100 km is the lithosphere. The lithosphere comprises both the crust and the upper brittle part of the mantle. The lithosphere is both the most rigid and the coolest layer of the Earth.
The asthenosphere is the weaker and denser layer below the lithospheric mantle. It is situated between 100 km and 410 km below the surface of the Earth. The pressure and the temperature of the asthenosphere are so much that the rocks soften and somewhat melts, turning into a semi-molten state.
The correct answer is C) At depths of about 50 to 200 hundred kilometers below the surface of the Earth.
To what depth below Earth's surface do you have to go before the pressure and temperature cause rocks to melt? At depths of about 50 to 200 hundred kilometers below the surface of the Earth.
The Asthenosphere is the layer of solid rock near its melting point. You can find magma at the Earth's core. Rocks melt into magma by three processes: Decompertion in the Mid-Ocean Ridge, the mountains chains under the water. Introducing volatile elements such as water or carbon dioxide. And Conductive heat.
The other options of the question were A) At depths of about 500 to 1000 hundred kilometers below the surface of the Earth, B) At the boundary of Earth's mantle and core, and D) At any point below Earth's crust.
