Petrology and petrography

Petrology & Petrography Petrology - The branch of geology dealing with the origin, occurrence, structure, and history of rocks. Petrography - The branch of geology dealing with the description and systematic classification of rocks, especially by microscopic examination of thin sections. Petrography is a subfield of Petrology. In this course, most of the lecture material falls under the field of Petrology, while much of the laboratory material falls in the field of Petrography