Murchison (Feb. 19, 1792 - Oct. 22, 1871) was a Scottish geologist who first differentiated the Silurian strata in the geologic sequence of Early Paleozoic strata (408-540 million years old). He believed in fossils as primary criteria. In 1831, he began researching the previously geologically unknown graywacke rocks of the Lower Paleozoic, found underlying the Old Red Sandstone in parts of Wales, which culminated in his major work the Silurian System (1839).
Murchison named the Silurian after an ancient British tribe that inhabited South Wales. He established the Devonian working with Adam Sedgwick (1839). He named the Permian (1841) after the Perm province in Russia where he made a geological survey in 1840-45. link
