Did you know that all of the rocks and minerals on Earth are products of the rock cycle? Here's how it works...
When magma melts and then crystallizes, it forms igneous rocks. There are two different types of igneous rocks: intrusive and extrusive. Intrusive igneous rocks are formed by magma that cools slowly beneath the surface of the Earth. These rocks have a course-grained texture; this means that there are many crystals present on their surfaces. Extrusive igneous rocks, which form from magma that cools quickly on Earth’s surface, have a fine-grained texture created by an absence of crystals.
Weathering encompasses all the processes that occur on or close to the surface of the Earth and that break down rocks and minerals into smaller pieces. Erosion happens when Earthen materials are transported by natural forces. Weathering breaks down rocks to create sediments, which are then moved by erosion.
What happens next?
After sediment is created, a process called lithification occurs. In this process, small pieces of sediment are compacted and cemented together to form sedimentary rocks. There are three types of sedimentary rocks: clastic, chemical, and organic. Clastic sedimentary rocks form when separate pieces of sediment are joined together to form a larger rock. Chemical rocks are composed of dissolved minerals, and organic rocks are formed from the remnants of living things (such as coal and fossils). Sedimentary rocks can sometimes melt to create magma that becomes igneous rocks.
Increases in temperature and pressure can then transform sedimentary and igneous rocks into metamorphic rocks. Foliated metamorphic rocks have dark and light stripes, while unfoliated rocks have an absence of banding. Metamorphic rocks can be broken down (via the processes of weathering and erosion) into sediments that are compacted and cemented into sedimentary rocks. They can also melt into magma that cools to become igneous rocks.