Principles of igneous and metamorphic petrology \ Принципы магматической и метаморфической петрологии

Igneous petrology is the study of melts (magma) and the rocks that crystallize from such melts, encompassing an understanding of the processes involved in melting and subsequent rise, evolution, crystallization, and eruption or emplacement of the eventual rocks. Origin by crystallization from a melt seems a simple enough criterion for considering a rock to be igneous. But we can only rarely observe the formation of igneous rocks directly, and then only for some surface lavas. The history of the study of igneous rocks is a tribute to the difficulties involved (see Young, 2003, for a comprehensive review). Many humans, including the Greeks, Romans/Italians, Japanese, Icelanders, and Indonesians, have lived with volcanoes. In the Western world, early biblical and Greek references to volcanic phenomena are generally attributed to angry gods. The Greek Hephaestus and later the Roman god Vulcan were gods of fire, and Romans considered volcanoes (particularly the island of Vulcano north of Sicily) as the chimneys of Vulcan’s forge. The Greeks and Romans recognized that volcanoes emitted fiery-hot lava (or explosive ash) and that lava cooled to stone. Several ancient scholars even proposed theories of volcanism. <...>