GILBERT, GROVE KARL (1843-1918), American geolo gist, was born at Rochester, N.Y., on May 6, 1843, and graduated at the University of Rochester in 1862. He began the study of geology and in 1869 went as a volunteer assistant on the second Ohio State survey. In 1871 he was assigned to the Wheeler survey and during his three years service took a remarkable trip by boat up the lower canyons of the Colorado river, by pack train through central Arizona and down the valley of the Gila, and again by boat down the Colorado to the Gulf of California. As a result of this trip he published two papers characterizing the basin range and plateau provinces and naming and describing ancient Lake Bonneville. He was transferred to the Powell survey in 1875 which took him to Utah, and with the formation of the U.S. geological survey in 1879, he was made one of the six senior geologists. In 1884 he was placed in charge of the Appalachian division of geology, and in 1889, upon the creation of the division of geologic correlation, he was placed at its head. After 1892 he relinquished most of his administrative duties and his position as chief geologist in order to return to the fuller study of some of his earlier problems. During this period his studies included the geology of Colorado, Mexico and Alaska, and he visited the latter with the Harriman expedition. The Bonneville Monograph, which he himself regarded as his magnum opus, was published in 189o. His report on the Geology of the Henry Mountains, in which the volcanic structure known as laccolite was first described, and his History of the Niagara River (189o) were of particular importance. He had much to do with planning the Federal Sur vey's bibliographic work and the adoption of principles of nomen clature and cartography, which form the basis of the survey's geologic map work. He died at Jackson, Mich. on May I, 1918.
See Bulletin of the Geological Society of America, vol. xxxi., pp. 26-64, which includes a complete bibliography of his publications; and N. M. Davis, American Journal of Science, 4th ser., vol. xlvi., pp. 669-681.