Grove Karl Gilbert
Grove Karl Gilbert ( born May 6, 1843 in Rochester, New York, † May 1, 1918 in Jackson, Michigan), known in the scientific literature, especially under the abbreviation GK Gilbert, was an American geologist.
Gilbert graduated from the University of Rochester. In 1871 he joined the first geologist with the team to George M. Wheeler, which carried out a geographical exploration of the Western United States. Then in 1874 he became the first assistant of John Wesley Powell in his exploration of the Rocky Mountains and remained there until in 1879. During this time he published an important work on the geology of the Henry Mountains (The Geology of the Henry Mountains, 1877). After the founding of the United States Geological Survey (USGS ) in 1879, he was appointed Chief Geologist, and later as Managing Director, and remained with the USGS until his death. He was on 13 January 1888 the founding members of the National Geographic Society.
1890 Gilbert published a study of Lake Bonneville which existed in the Pleistocene in Utah and the rest of the Great Salt Lake is. He named the lake after the army officer Benjamin LE de Bonneville (1796-1878), who had explored this region before him.
In 1891, he declared in one of the most controversial theories of his career, the Barringer Crater in Arizona as the result of a maar - explosion and dismissed the statement by the impact of a meteorite. Gilbert based his conclusion that the volume of ejected material must be greater along with the meteorite than that of the ejected material around its edge, and that the meteoric should summon an anomaly of the geomagnetic field. Gilbert's studies and calculations led to the conclusion that the volume of the ejected material is approximately equal to the crater, and that no magnetic anomaly is present. The now and then at the edge of the crater to be found meteorite fragments he saw as a coincidence. Gilbert published his conclusions in a series of lectures in 1895. Later studies showed, however, that the crater is actually caused by a meteorite. This episode in Gilbert's life is not without a certain irony, since he was one of the first scientists rejected the volcanic origin of the lunar craters and led her back to meteorite impacts, and later undertook experiments formation of craters by meteorite impacts.
He joined in 1899 Harriman Alaska Expedition, the Alaskan coast skirted two months and attended by, among others, William Trelease, Theodore Pergande, Edward Curtis and Robert Ridgway.
Gilbert was one of the most influential early American geologists, a geo-scientific pioneer, and is regarded as one of the " giants " of the geomorphology. He contributed to the understanding of landscape development, gained important insights into erosion, cutting of rivers in their ground and the process of sedimentation.
In 1900 he won the Wollaston Medal of the Geological Society of America. The Mars crater Gilbert is named after him and the lunar crater after him Gilbert and physician William Gilbert. In his honor, the GK Gilbert Award, the Geological Society of America for work awarded in planetary geology and the GK Gilbert Award for Excellence in Geomorphic Research.