20th-century American geologists

American geologist and astronomer

American astronaut (born 1951)

American oceanographer and cartographer (1920–2006)

American geologist (1862–1945)

American schoolteacher (1900–1970)

American geophysicist and planetary scientist (1959-2015)

American geoscientist (1903–1989)

28th Governor of Nevada

American geophysicist and marine geologist (born 1942)

American volcanologist (1949–1980)

American geologist (1841–1912)

gymnast (1911-1997)

American geologist (1924-1977)

American geophysicist

American-Canadian geologist and palaeontologist (1937-2019)

American earth scientist, biogeologist, cosmologist, and paleontologist (1912–1991)

American astronomer

American geologist, geographer, researcher and university teacher

Under Secretary for Science and Research at the Smithsonian Institution

American paleoclimatologist

Italian-American scientist, geologist, micropaleontologist, and founder of paleoceanography

American scientist (1914–1995)

American geologist, mineralogist and historian of science (1921-2018)

American geologist and paleontologist

American geologist

American geologist, palaeontologist, teacher and philanthropist (d. 1906)

American paleontologist (1899-1995)

American petroleum geologist and paleomicrobiologist (1895-1972)

Croatian oil explorer (1855-1921)

U.S. botanist & paleoecologist (1910-1998)

American geophysicist (1903–1992)

American geomorphologist and hydrologist (1915–2006)

American geologist

American geologist and volcanologist

American scientist

American engineer and geodesist (1872–1940)

U.S. paleontologist, zoologist, and geologist (1910–1993)

American geologist who discovered the Missoula Floods (1882-1981)

American geologist (1882-1960)

American geologist

American paleontologist and zoologist (1893–1975)

American sedimentologist (1897-1985)

American geologist (1958-1991)

American ornithologist (1909–1962)

American geophysicist

American geologist (1902-1976)

American paleontologist and curator at the American Museum of Natural History (1909–2005)

Russian-born American geologist, friend of Lee Harvey Oswald (1911-1977)

U.S. paleontologist, cnidariologist, and geologist (1907–1994)

American geologist and crystallographer

American paleontologist (1914-2007)

American scientist (1888–1965)

American geologist and paleontologist (1916–2014)

American geologist (1841-1927)

American geologist (1873 - 1941)

American geologist (1839-1914)

American geologist (1904–1975)

American geologist

American paleontologist (1888-1971)

American geographer and oceanographer