Question

what kinds of processes can cause rocks to change?

Answer 1

1.Heat:Heat can cause rock to melt,forcing real changes in its chemical and physical makeup;forcing some elemental components to chemically react with each other,both internal and external,chemical components to form entirely new material. 
another way is erosion 

Answer 2

lets see here 1.Heat:Heat can cause rock to melt,forcing real changes in its chemical and physical makeup;forcing some elemental components to chemically react with each other,both internal and external,chemical components to form entirely new material. 
another way is erosion