Metamorphism is the solid-state change of a rock in response to a modification to its environment. From the list below, select four environmental changes that are most responsible for causing metamorphism. Change in groundwater pH Application of stress Increase in pressure Physical erosion Increase in temperature Exposure to hydrothermal fluids ⢠. . 2. In order to understand metamorphic rocks, it is important that we are able to use the nomenclature correctly. Below are several terms specific to metamorphic rocks. Match each term with its appropriate definition. Term Definition Protolith The apparent layering within a rock due to the alignment of minerals. Foliation A broad region of continental crust where Precambrian-aged rocks are exposed. Shield A set of metamorphic minerals formed at a specific range of pressures and temperatures. Metamorphic Facies The original rock that undergoes solid-state change during metamorphism.