Which is needed to turn an igneous rock or sedimentary rock into a metamorphic rock?(1 point)
Responses
freezing and cementation
freezing and cementation
erosion and deposition
erosion and deposition
melting and cooling
melting and cooling
heat and pressure
heat and pressure
The correct answer is heat and pressure.
The correct answer is "heat and pressure."
To understand why heat and pressure are needed to turn an igneous rock or sedimentary rock into a metamorphic rock, let's break it down:
1. Heat: Heat refers to an increase in temperature. When an igneous or sedimentary rock is subjected to high temperatures, it undergoes metamorphism. This increased heat causes the minerals within the rock to recrystallize, resulting in the formation of metamorphic rock.
2. Pressure: Pressure refers to the force applied uniformly over an area. When an igneous or sedimentary rock is subjected to high pressure, it also undergoes metamorphism. The increased pressure causes the minerals within the rock to rearrange and align, resulting in the formation of a metamorphic rock.
Combining heat and pressure alters the mineral composition, texture, and structure of the rock, transforming it into a metamorphic rock.
Now, let's look at the other answer choices and explain why they are incorrect:
- Freezing and cementation: Freezing and cementation are processes associated with the formation of sedimentary rocks. They involve the solidification of sediment particles, such as grains or fragments, through the binding of materials like minerals or organic matter. However, these processes do not lead to metamorphic rock formation.
- Erosion and deposition: Erosion and deposition are part of the processes that create sedimentary rocks. Erosion involves the wearing away and transport of rock and sediment, while deposition is the settling and accumulation of these materials. Although these processes are important in the rock cycle, they do not directly contribute to the formation of metamorphic rocks.
- Melting and cooling: Melting and cooling are related to igneous rock formation. When rocks melt due to increased temperatures, they form molten magma. Upon cooling and solidification, this magma forms igneous rocks. However, melting and cooling alone do not create metamorphic rocks.
In summary, the processes that are specifically required to transform an igneous or sedimentary rock into a metamorphic rock are heat and pressure.