The science of geology in the United States developed almost simultaneously with the exploration of the continent, and the continent's geology profoundly affected the scientists who studied it. Geologists pondered such basic questions as the age and nature of the rocks, how they had been deposited, and the meaning of the fossils they contained. But geologists were also driven by the need to understand the rocks for mining and, later, petroleum exploration. In short, the history of geology in America is rooted in the physical context of the land and its natural resources.
After the first wave of European exploration, mapping, particularly geologic mapping, provided the benchmark for later study. Much of that early mapping was based on European ideas and methods; the Englishman William McClure completed the first widely published geologic map of the United States in 1809. Early geology was, for the most part, a subset of natural history, and much of the groundwork was done by faculty who taught natural history at American colleges. Yale's Benjamin Silliman established the American Journal of Science (1818), known colloquially as Silliman's Journal, and published extensively on geology. His student and son-in-law James Dwight Dana later took over the editorship of the journal and wrote books that helped to systematize mineralogy. Parker Cleaveland of Bowdoin College became famous for his landmark Elementary Treatise on Mineralogy and Geology (1816).
Gradually, geology emerged as a separate discipline. In 1840 the Association of American Geologists and Naturalists held its first annual meeting; eight years later it became the American Association for the Advancement of Science. Another sign of maturation was the establishment of state geological surveys, an early example of government-supported science in the United States. The North Carolina survey, launched in 1823, was first. Several prominent geologists of the early nineteenth century worked with these surveys, including James Hall of New York, David Dale Owen of Indiana, and William Barton Rogers of Virginia.
The accomplishments of these and other figures derived in part from the development of the nation's infrastructure. The construction of bridges, roads, canals and waterways, and railroads—combined with scientific curiosity and the economic importance of locating minerals such as salt and coal—provided ample motivation for detailed geological research. Pre–Civil War exploring expeditions set an example for the great federal surveys of the American West after the war. These surveys provided a wealth of knowledge about regional geology and often captured the public's imagination. Clarence King studied the mountain country of California, Nevada, and Utah. Ferdinand V. Hayden made detailed geologic studies in Colorado, Wyoming, and Nebraska, and did much to bring about the creation of Yellowstone National Park in 1872. George M. Wheeler took stock of Arizona and Nevada. The best-known of these intrepid early geologists, John Wesley Powell, a one-armed Civil War veteran, explored the Colorado Plateau and led a celebrated 1869 trip through the Grand Canyon. From all this activity grew the U.S. Geological Survey, created in 1879, with first King and then Powell as its head. Under Powell it became the premier example of government-sponsored science in America. In retrospect, this post–Civil War era assumed heroic status in American geology. With expansion across the West came a host of new natural knowledge, not only about mineral resources but about the history of the earth and life as well.
Fossil discoveries by such figures as Edward Drinker Cope, Othniel Charles Marsh, and Joseph Leidy contributed to American leadership in vertebrate paleontology and provided compelling evidence of organic evolution. The studies of Utah's ancient Lake Bonneville by Grove Karl Gilbert advanced the science of geomorphology. With hard-rock mining and especially the growth of the petroleum industry came extensive new information about subsurface geologic structures, such as anticlines. Studies of the Rocky Mountains and the Appalachian Mountains led to new theories of mountain formation. Examination of interbedded limestones and shales on the Great Plains improved understanding of sedimentation. Later, in the first half of the twentieth century, geophysical techniques, such as seismic reflection, became especially important, and various subdisciplines of geology, such as geochemistry, stratigraphy, sedimentology, and geohydrology, matured and grew.
The most notable development in twentieth-century geology was plate tectonics: the realization that the land could move. Building on the ideas of Germany's Alfred Wegener, geologists marshalled new evidence, such as that supplied by Americans Maurice Ewing and Harry Hess concerning sea-floor spreading, to support the concept and pave the way for the theory's general acceptance. After the 1960s and the advent of plate tectonics, geology became increasingly quantified and computerized. Geologists used a variety of new methods, such as deep-ocean drilling, planetary and space science, and remote sensing, to learn more about the earth. Late twentieth-century geologists faced issues of large social import: supplying energy and natural resources, dealing with environmental contamination, and mitigating geologic hazards such as earthquakes and volcanoes. They also encountered questions of popular interest, such as meteor-impact theories and the demise of the dinosaurs. And they continued to confront the basic intellectual challenges of understanding the earth's past and its deep subsurface, pondering places in the planet that no one had ever been to or seen.
Richard A. Bartlett, Great Surveys of the American West, 1962.Find this resource:
Mary C. Rabbitt, Minerals, Lands, and Geology for the Common Defence and General Welfare, 3 vols., 1979–1986.Find this resource:
Cecil J. Schneer, ed., Two Hundred Years of Geology in America: Proceedings of the New Hampshire Bicentennial Conference on the History of Geology, 1979.Find this resource:
Henry Faul and Carol Faul, It Began with a Stone: A History of Geology from the Stone Age to the Age of Plate Tectonics, 1983.Find this resource:
Ellen T. Drake and William M. Jordan, eds., Geologists and Ideas: A History of North American Geology, 1985.Find this resource:
Mott T. Greene, History of Geology, Osiris 1, 2d series (1985) 97–116.Find this resource: