Rock Cycle Process

The Rock Cycle

• The rock cycle is the natural Earth process of how rocks form and convert between types.
• There are three types of rocks: igneous, metamorphic, and sedimentary.
• Rocks can take anywhere from hundreds to thousands of years, to millions of years to form or change types.

Igneous Rocks

• Igneous rocks form from magma or lava, which is liquid rock.
• Magma or lava crystallizes and forms igneous rocks.
• Igneous rocks can be transformed into metamorphic rocks through intense heat and pressure.
• Igneous rocks can be weathered and eroded into sediment and cemented into sedimentary rocks.
• Igneous rocks can also be transformed back into magma.

Sedimentary Rocks

• Sedimentary rocks form from sediments that are broken off other rocks and cemented back together.
• Sediments are formed from metamorphic and igneous rocks and even other sedimentary rocks.
• Weathering is the first step in the sedimentary rock cycle, where tiny pieces break off the original rock.
• Erosion moves the broken pieces of rock away, usually caused by water or wind.
• Sediments are transported and deposited through erosion processes.
• Compaction and cementation are the processes by which sediments stick together to form sedimentary rocks.

Types of Sedimentary Rocks

• Clastic sedimentary rocks form through the basic sedimentary process.
• Bioclastic sedimentary rocks contain pieces of living matter, such as shells or bones.
• Organic sedimentary rocks are formed from the remains of plants and animals, such as coal.
• Chemical sedimentary rocks are formed through the precipitation of minerals from a solution.

Metamorphic Rocks

• Metamorphic rocks are formed from igneous, sedimentary, or other metamorphic rocks through intense pressures and heat.
• Metamorphic rocks physically and chemically change as a result of these processes.
• There are two main processes of metamorphism: contact metamorphism and regional metamorphism.
• Metamorphic rocks can be foliated or non-foliated, with foliated rocks having visible layers.

Rock Cycle Examples

• Sediments and rocks can be buried through natural geological processes over time, leading to metamorphism.
• Metamorphic rocks can melt into magma and crystallize as igneous rocks.
• Igneous rocks can be weathered and eroded away, becoming sedimentary rocks again.
• These processes demonstrate the rock cycle, where rocks can change types through geological processes.