An introduction to metamorphic petrology / Введение в петрологию метаморфических горных пород

Metamorph;c processes have been taking place on a massive scale throughout the Earth's history, and have affected the bulk of the rocks now present in the crust. Despite this, they are not as well understood as sedimentary or volcanic processes, because metamorphism can scarcely ever be observed directly, and the study of metamorphic rocks is instead based on observation, inference and logic, founded in relatively simplistic experimental studies and the basic principles of chemistry and physics