Final answer:
Metamorphic rocks are formed when a pre-existing rock is altered by heat, pressure, or chemical fluids, resulting in a new rock with a different mineral composition and texture, such as the transformation of limestone to marble or shale to slate.
Step-by-step explanation:
The process described in the question refers to the formation of metamorphic rocks, which occur when a pre-existing rock, known as the protolith or parent rock, is subjected to changes in temperature, pressure, or chemical reactions, particularly through the presence of fluids. This phenomena brings about a transformation, where the minerals within the rock recrystallize without melting, forming a new rock with a different mineral composition and structure. Factors like the nature of the original rock and the intensity of temperature and pressure influence the attributes of the resultant metamorphic rock. Examples include the transformation of limestone into marble, and shale into slate.
Metamorphism is often associated with mountain-building processes where rocks are buried or subjected to intense heat from nearby magma intrusions. This may lead to a foliated texture with minerals aligned in sheets or bands, as seen in rocks like schist and gneiss. The scale of the temperature, pressure, and the presence of chemically reactive fluids, define the type of metamorphic rock that will ultimately form.