Igneous petrology Igneous petrology Igneous petrology is the study of igneous rocks—those that are formed from magma. As a branch of geology, igneous petrology is closely related to volcanology, tectonophysics, and petrology in general. The modern study of igneous rocks utilizes a number of techniques, some of them developed in the fields of chemistry, physics, or other earth sciences. Petrography, crystallography, and isotopic studies are common methods used in igneous petrology. The composition of igneous rocks and minerals can be determined via a variety of methods of varying ease, cost, and complexity. The simplest method is observation of hand samples with the
What Is Literature? What Is Literature? What Is Literature? (), also published as "Literature and Existentialism",) is an essay by French philosopher and novelist Jean-Paul Sartre, published by Gallimard in 1948. Initially published in freestanding essays across French literary journals "Les Temps modernes", "Situations I" and "Situations II", essays "What is Writing?" and "Why Write?" were translated into English and published by the Paris-based literary journal Transition 1948. The English translation by Bernard Frechtman was published in 1950. Sartre attempts to devise an understanding of the effect literature has on those who are subjected to it. In the foreword Sartre addresses his critics