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
Here Is What Is Here Is What Is Here Is What Is is the fifth studio album by Canadian songwriter and record producer Daniel Lanois. It was first released in December 2007 as a high-quality download, and later released on CD on March 18, 2008. The album is the result of the same project that led to the 2007 documentary "Here Is What Is" that premiered at the 2007 Toronto International Film Festival in September. The movie documents the aesthetics and creative process behind Lanois' approach to music making and recording. The album has been presented as a direct soundtrack to this film, and