Sir Roderick Impey Murchison ( 1792-1871), developed the modern classification of the Palaeozoic period, through his research emphasising biostratigraphy; the deposition of strata indicated by fossils. In the course of his career he successively defined the Silurian, Devonian and Permian strata, which replaced Greywacke and Coal Measures in the scientific literature.
After serving with the army in the Peninsula War and a period of time pursuing his interest in hunting, the independently wealthy Murchison began attending lectures at the Royal Institution. In 1825 he joined the Geological Society of London. Shortly afterwards he read the society his first paper, on the geology of parts of Sussex, Hampshire and Surrey. In the following five years Murchison made field explorations to Scotland, France, and the Alps with either Adam Sedgwick or Charles Lyell. In 1831 he began a study of the Early Palaeozoic rocks in South Wales. These studies were the basis of his defining work The Silurian System, ( 1839) . Further geological research in south western England and the Rhineland, in collaboration with Adam Sedgwick, defined the Devonian System. Russian field expeditions, in conjunction with French colleagues, became the basis for the definition of the Permian System. These expeditions also resulted in his works The Geology of Russia in Europe, ( 1845) and The Ural Mountains, ( 1845) . Successive editions of his expanded treatise on the Silurian System, Siluria, ( 1854) (5th ed. 1872) were also prepared. Latterly he became interested in encouraging geographical exploration and colonialism.
Murchison was president of the Geological Society of London in both 1831-1832 and 1842-1843 and became long term president of the Royal Geographical Society in 1844. As one of the founders of the British Association he was elected president for 1846. He was knighted in 1846 and also awarded the Russian Order of St. Stanislaus of the 1st Class. Appointments as director general of the Geological Survey of Great Britain, and director of the Government School of Mines and the Museum of Economic Geology, London, followed in 1855. From 1863-1871 he was Patron of the Edinburgh Geological Society during which time he was raised to a Baronet. In 1871 he founded a Chair of Geology and Mineralogy at the University of Edinburgh.