1. Geothermal Gradient: The Earth's interior is hot, and the temperature increases with depth. This natural heat flow, known as the geothermal gradient, provides a constant source of heat.
2. Magma Intrusions: When molten rock (magma) rises from the Earth's mantle and intrudes into existing rocks, it brings a tremendous amount of heat with it. This heat can bake and transform the surrounding rocks, creating metamorphic rocks.
These heat sources can work individually or together to transform existing rocks into metamorphic rocks.
Here's a breakdown:
* Contact Metamorphism: This type of metamorphism occurs when rocks are heated by the intrusion of magma or lava. It's characterized by localized changes in the rocks near the intrusion.
* Regional Metamorphism: This type of metamorphism occurs over large areas due to the geothermal gradient and the pressure exerted by tectonic forces. It often happens in areas where mountains are being formed.
In addition to heat, pressure also plays a crucial role in the formation of metamorphic rocks.
