[Solved] Describe the main issues behind the debates regarding whether adolescents who text or email nude photos of themselves should be charged with child pornography. Mantle Convection: Movement of mantle material in response to variations in density, especially those caused by differences in temperature. Asthenosphere: A semi-fluid layer beneath the Earth's lithosphere on which the tectonic plates move, located in the upper mantle between approximately 100 and 250 kilometers deep. Density: A measure of mass per unit volume of a substance, influencing how materials interact, such as floating or sinking in water. Slab Pull: A mechanism that contributes to plate tectonics, involving the subduction of oceanic plates pulling the trailing lithosphere into subduction zones.