Understanding the Rock Cycle

The rock cycle deals with the changes that rocks undergo over time due to natural influences of weathering, erosion, pressure, and heat. While short-term changes may not be noticeable even in one’s life time over millions of years these changes are often quite extraordinary. The concept of the rock cycle was pioneered by James Hutton.  His work led him to be known as the father of modern Geology. It explains how rocks are never truly destroyed. Instead they are constantly being recycled and changing forms becoming other rocks in the process.

Deep within the earth molten lava boils and churns with incredible heat and pressure. Over time as this rock cools it produces igneous rock that reaches the surface through uplift or processes of erosion. Igneous rock that reaches the surface this way is called intrusive igneous rocks and the cool in the outer layers of the Earth’s crust. Igneous rock is also distributed to the surface effectively during volcanic eruptions. Rocks deposited this way are known as extrusive igneous rock as cool rapidly once reaching the surface. Metamorphic rocks are also created deep in the Earth depending on the heat and pressures involved reach the surface through erosion and uplift. Once these rocks reach the surface they are immediately exposed to weathering and erosion. Rain and wind constantly bombard these rocks eventually causing particles or sediments to break off. Wind and rain then carried these sediments depositing them elsewhere.

Over time sediments will begin to become compacted as more and more material is added. As the pressure increases sediments begin to bond together as sedimentary rock. Once sedimentary rock has formed in will either be influenced by erosion and break off into smaller sediments or be subjugated to the heat and pressure deep in the Earth’s surface. Sedimentary rocks that react to heat and pressure will eventually become metamorphic rock. Once they reach this state they may surface and be exposed to the elements eventually breaking down into sediments to begin the process of becoming sedimentary rock once again. If they don’t surface they will melt down becoming magma where they will surface through volcanic activity to begin the process all over again.

The rock cycle is a looped process and at any given time a rock will be at some stage of the process. The crust is constantly recycling itself over millions and millions of years. Understanding the rock cycle is incredibly important to geologist. They can use this information to learn about geological features of a particular area. Understanding geological features helps better predict how interactions with elements may change the rock. Features of rock are studied to locate resources such as oil, gas, and water. Understanding rock and the processes that created in makes locating these resources much easier. Understanding rock cycles may one day help scientist to better predict earthquakes and volcanic eruptions.