The process by which rock is gradually brought up to the earth's surface is called uplift. Uplift can occur due to a variety of factors, including tectonic plate movement, volcanic activity, and erosion. When tectonic plates collide, one plate may be forced beneath the other, causing the rocks on the upper plate to be uplifted. Volcanic activity can also cause uplift, as the magma rises and pushes the rocks above it upwards. Finally, erosion can cause uplift by removing the overlying layers of rock, exposing the rocks beneath.