Petrology description of rocks while petrography is the speciality that deals with microscopic details. In the petroleum industry, lithology, or more specifically mud logging, is the graphic representation of geological formations being drilled through, and drawn on a log called a mud log. As the cuttings are circulated out of the borehole they are sampled, examined (typically under a 10× microscope) and tested chemically when needed. Petrology utilizes the fields of mineralogy, petrography, optical mineralogy, and chemical analysis to describe the composition and texture of rocks. Petrologists also include the principles of geochemistry and geophysics through the study of geochemical trends
What Is Life love song – perhaps a "lovingly crafted paen" to Harrison's wife Pattie, as Alan Clayson puts it – or a devotional song like many of Harrison's compositions. Ian Inglis writes that the song title suggests a "philosophical debate about the meaning of life", yet its rendering as ""what is my life"" in the choruses "reshapes [the meaning] completely". Theologian Dale Allison finds no religious content in "What Is Life" but notes the "failure of words to express feelings" implied in the opening line (""What I feel, I can't say""), a recurring theme of Harrison's spiritual songs such as "That Is