The Rock Cycle This is a picture explaining the rock cycle. The place to start at is the magma chamber. As you can see the magma comes out of the volcano and cools into igneous rocks. Next, the igneous rocks erode and turn into sediments. The sediments go through years of pressure and cementation which turns the sediments into sedimentary rock layers. Once again the rocks go through heat and pressure and turn into metamorphic rocks like at the start. Then the new metamorphic rocks go through heat and turn into magma. That is how the rock cycle works.