This process, which occurs in "regional" and "contact" subtypes, starts with a protolith and results in products such as marble, slate, and gneiss.
Pentti Eskola proposed a system for classifying the conditions under which this process occurs. The presence of the stishovite and coesite polymorphs of silicon dioxide may indicate the occurrence of a particularly violent type of this process. A saltwater-mediated hydrothermal type of this process that occurs at black smokers creates deep-sea deposits of copper and nickel ore. Akiho Miyashiro proposed the existence of parallel paired belts named for this process that have contrasting (*) mineralogy. The relative degree, or grade, of this process is measured by examining index minerals. Shearing forces during this process can result in foliation. This process, which occurs in "regional" and "contact" subtypes, starts with a protolith and results in products such as marble, slate, and gneiss. For 10 points, name this geological process in which the application of heat and pressure changes a rock from one type to another.
Pentti Eskola proposed a system for classifying the conditions under which this process occurs.
metamorphism