Igneous petrology such as Science and Nature. Study material, overviews of certain topics and older works are often found as books. Many works before the plate tectonics paradigm shift in the 1960s and 1970s contains inaccurate information regarding the origin of magmas. 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
What Is the Third Estate? What Is the Third Estate? What Is the Third Estate? () is a political pamphlet written in January 1789, shortly before the outbreak of the French Revolution, by the French thinker and clergyman Abbé Emmanuel Joseph Sieyès (1748–1836). The pamphlet was Sieyès' response to finance minister Jacques Necker's invitation for writers to state how they thought the Estates-General should be organized. In the pamphlet, Sieyès argues that the third estate – the common people of France – constituted a complete nation within itself and had no need of the "dead weight" of the two other orders, the first and second