Where Does It Begin?
The rock cycle is a concept originally attributed to James Hutton. He is most widely noted for developing the idea that these three types of rocks undergo a consistent, repetitive cycle. Essentially, the rock cycle is the basic geological theory of the Earth’s formation. It consists of the process that sedimentary, igneous and metamorphic rocks undergo to transition between rock forms, during which they move between forms in a gradual evolving process.
Every rock is composed of minerals, which are defined as crystalline solids made from a distinct chemical composition that have a specific formation, and which occur in nature. Rocks are defined as inanimate, firm masses of solid matter formed naturally which make up part of a planet. So how is the rock cycle formed?
What is the Igneous Transition?
The igneous transition is often considered to be the first step in the rock cycle. The transition to igneous rock occurs when they are pushed deep into the core of the Earth. This causes the rocks to melt into magma. Once the magma cools and no longer remains in the liquid state, it forms into a solid known as igneous rock. Igneous rocks will often later reappear in the rock cycle and once again be transformed into magma.
Igneous rocks can easily be broken down into smaller particles, thanks to the atmospheric decomposition of the Earth. As the rocks fall victim to the weathering process of the planet, such as rain and frost; the mineral components begin to change and break away. This can occur to such an extent that the rocks eventually become fine particles.
What is the Metamorphic Transition?
The metamorphic transition is the second form of the rock cycle. This transition begins when rocks are altered due to high pressures or temperatures. As a rule, this occurs thanks to the pressure of thousands of feet of bedrock above which crush the rocks or sediment. This causes the rocks to change physically and chemically into an entirely different rock form. All three forms of rocks included in the rock cycle can undergo the transition to become metamorphic rocks. Metamorphic rocks are even able to undergo the transition and become other forms of metamorphic rocks.
What is the Sedimentary Transition?
The sedimentary transition occurs when rocks are exposed to excessive weathering, which can then cause erosion. This causes the rocks to break down into smaller particles and even be carried away by rain water or other forms of erosion. This rock material that has been washed away then begins to accumulate in other areas. Eventually, these fragments will be fused together through cementing, compacting or hardening, as they undergo the sedimentary transition. In rare cases, the fusion can actually occur due to a chemical process. However, it’s more common that the fusion occurs as weight and pressure on top of the sediment crushes it together, causing the transition. The accumulation and fusion process can continue until the rocks undergo another transition of the rock cycle.
For more information on how the rock cycle is formed and examples of the various types of rock forms, click here.
“What is the Rock Cycle?” IMNHH.edu
"The Rock Cycle" RocksandMinerals.org
"The Rock Cycle" Washington.edu