Here's why:
* Contact metamorphism occurs when existing rocks are altered by the heat and pressure from an igneous intrusion. This process can transform various pre-existing rock types (sedimentary, igneous, or metamorphic).
* The resulting rock type depends on the original rock's composition and the intensity of the metamorphism.
For example:
* Limestone subjected to contact metamorphism can transform into marble.
* Sandstone might become quartzite.
* Shale can turn into hornfels.
So, instead of a single type, contact metamorphism produces various metamorphic rocks depending on the starting material.
