Petrology has three subdivisions&colon; igneous, metamorphic, and sedimentary petrology. Major focuses include geochronology, comparative geology, and petrology. Petrography, crystallography, and isotopic studies are common methods used in igneous petrology. Phase rule is very useful in diverse areas, such as metallurgy, mineralogy, and petrology. These concepts are also applicable to metamorphic and sedimentary petrology. He's also the vice-president of the "Chinese Society for Mineralogy, Petrology and Geochemistry". The scientific study of rocks is called petrology, which is an essential component of geology. They can be measured in numerous different ways, including surface heat flow, petrology, and seismology. The petrology of the Honolulu Volcanics is well studied. Melting of eclogite to produce basalt directly is generally not supported in modern petrology. Bowen ""revolutionized experimental petrology and our understanding of mineral crystallization"". He obtained a Ph.D. by studying petrology at the Heidelberg University. This book became "the" petrology handbook. This experiment yielded information on the petrology of the surface material on the Moon. Such temperatures have not yet been confirmed by petrology, however.