Earthвђ™s Mantle Is Review
: Extending from the crust to about 410 km deep, it includes the lithosphere (the rigid top layer) and the asthenosphere , a semi-fluid zone that allows tectonic plates to slide.
: The mantle acts as a thermal blanket, slowly releasing the primordial heat from Earth’s formation and the radioactive decay of elements, maintaining the planet's internal temperature balance. Earth’s mantle is
The mantle is essential for life on Earth for several reasons: : Extending from the crust to about 410
The mantle is approximately 2,900 kilometers (1,802 miles) thick and is primarily composed of rocks rich in magnesium and iron, such as . While it is solid rock, it behaves like an extremely viscous fluid over millions of years—a property known as plasticity. It is generally divided into three main sections: While it is solid rock, it behaves like
: Stretching from 660 km down to the core-mantle boundary, this region is under such immense pressure that the rock remains solid despite temperatures exceeding 3,000°C. Why It Matters