Metamorphic rock the foliation is called "gneissosity"), granoblastic (includes granulite, some marbles and quartzite), and hornfelsic (includes hornfels and skarn). Metamorphic rock Metamorphic rocks arise from the transformation of existing rock types, in a process called metamorphism, which means "change in form". The original rock (protolith) is subjected to heat (temperatures greater than 150 to 200 °C) and pressure ( or more), causing profound physical or chemical change. The protolith may be a sedimentary, igneous, or existing metamorphic rock. Metamorphic rocks make up a large part of the Earth's crust and form 12% of the Earth's land surface. They are classified by
Heat of 'heat content'. It is sometimes also called the heat function. In terms of the natural variables of the state function , this process of change of state from state 1 to state 2 can be expressed as It is known that the temperature is identically stated by Consequently, In this case, the integral specifies a quantity of heat transferred at constant pressure. As a common noun, English "heat" or "warmth" (just as French "chaleur", German "Wärme", Latin "calor", Greek θάλπος, etc.) refers to (the human perception of) either thermal energy or temperature. Speculation on thermal energy or "heat" as