Metamorphic rock transforms into sedimentary rock through a process where it is broken down into sediment and then compacted. This transformation is a fundamental part of the Earth's rock cycle.
At the surface, metamorphic rocks will be exposed to weathering processes and may break down into sediment.
The Process: From Metamorphic to Sedimentary
Here's how metamorphic rock undergoes the change into sedimentary rock:
- Weathering: When metamorphic rocks are exposed at the Earth's surface, they are subject to weathering. This involves physical and chemical processes that break the rock into smaller pieces.
- Breakdown into Sediment: As a result of weathering, the metamorphic rock may break down into sediment. This sediment consists of loose grains of rock, mineral fragments, and other materials.
- Transport and Deposition: These sediments are often transported by natural forces like water, wind, or ice and eventually deposited in layers.
- Compaction: Over time, as more layers of sediment accumulate on top, the weight of the overlying material causes the sediments to be compressed. This squeezes out water and reduces the space between the sediment grains.
- Cementation (Implied by Formation of Sedimentary Rock): While the reference specifically mentions compression, the formation of solid sedimentary rock also typically involves cementation, where mineral-rich water flows through the sediment and deposits minerals that bind the grains together.
- Formation of Sedimentary Rock: The combination of compression and cementation turns the loose sediment into solid sedimentary rock.
This process effectively recycles the material from the metamorphic rock, forming a new sedimentary rock, which can start the entire cycle anew.
