Question

why do igneous and sedimentary rocks sometimes get changed? what are the new rocks called?​

Answer 1

Answer:

If the original igneous and sedimentary rock is subjected to heat (greater than 150 degree Celcius) and pressure (greater than 1500 bars), it changes into new a new type of rock. The new rock type is called metamorphic rock. Examples are change of granite into gneiss and the change of shale into slate.

Answer 2

If the original igneous and sedimentary rock is subjected to heat (greater than 150 degree Celcius) and pressure (greater than 1500 bars), it changes into new a new type of rock. ... The new rock type is called metamorphic rock.