How is this circular motion achieved? heat ‘"pushes" the magma up, and when it hits the lithosphere it is pushed back down towards the core. heated magma is magnetic and is drawn to the lithosphere where it loses its magnetic force and drops back down due to gravity. heated magma rises from the core, but rocks in the asthenosphere block the magma on each side, causing it to move in small circles. hot magma rises and pushes up toward the lithosphere, and as it cools it cycles back down toward the core to be heated again.