Earth's lithosphere<span> includes the crust and the uppermost mantle, which constitute the hard and rigid outer layer of the Earth. The </span>lithosphere is<span>subdivided into tectonic plates. ... The </span>lithosphere is<span>underlain by the asthenosphere which </span>is<span> the weaker, hotter, and deeper part of the upper mantle</span>
Answer:
Movement in the mantle caused by variations in heat from the core, cause the plates to shift, which can cause earthquakes and volcanic eruptions.