Petrology Petrology Petrology (from the Greek πέτρος, "pétros", "rock" and λόγος, "lógos", "subject matter", see -logy) is the branch of geology that studies rocks and the conditions under which they form. Petrology has three subdivisions: igneous, metamorphic, and sedimentary petrology. Igneous and metamorphic petrology are commonly taught together because they both contain heavy use of chemistry, chemical methods, and phase diagrams. Sedimentary petrology is, on the other hand, commonly taught together with stratigraphy because it deals with the processes that form sedimentary rock. Lithology was once approximately synonymous with petrography, but in current usage, lithology focuses on macroscopic hand-sample or outcrop-scale
What Is History? and were instead products of their own places and times, which in turn decided what "facts of the past" they determined into "facts of history". British historian Richard J. Evans said "What Is History?" caused a revolution in British historiography in the 1960s. Australian historian Keith Windschuttle, a critic of Carr, said "What Is History?" is one of the most influential books written about historiography, and that very few historians working in the English language since the 1960s had not read it. What Is History? What Is History? is a study that was written by the English historian E. H.