Catastrophism

Catastrophism is the argument that Earth's features—including mountains, valleys, and lakes—primarily formed and shaped as a result of the periodic but sudden forces as opposed to gradual change that takes place over a long period of time.

Although geologists may argue about the extent of catastrophism in shaping the earth, modern geologists interpret many formations and events as resulting from an interplay catastrophic and uniform forces that result in more slowly evolving change.

For example, according to strict catastrophe theory, one might interpret the origins of the Rocky Mountains or the Alps, as resulting from a huge earthquake that uplifted them quickly. When viewing the Yosemite Valley in California a catastrophist might not assert they were carved by glaciers , but rather the floor of the valley collapsed over 1,000 ft (305m) to its present position in one giant plunge. Strict catastrophic theory also argues for long periods of inactivity following catastrophic events.

In terms of modern geoscience, strict catastrophic theory (e.g., a world shaped by large single floods , or massive earthquakes) finds little evidence or support. Catastrophism developed in the seventeenth and eighteenth centuries when, by tradition and even by law, scientists used the Bible and other religious documents as a scientific documents.

For example, when a prominent theologian, Irish biblical scholar Bishop James Ussher in the mid-1600's work, Annals of the World, counted the ages of people in the Bible and proclaimed that Earth was created in 4004 b.c. (In fact, Ussher even pronounced an actual date of creation as the evening of October 22), geologists tried to work within a time frame that encompassed only around six thousand years. (Current research estimates Earth at 4.5 billion years old.) In its original form, catastrophism eventually fell from grace with the scientific community as they reasoned more logical explanations for natural history. A new concept, known as uniformitarianism , eventually replaced catastrophism. Uniformitarianism is the argument that mountains are uplifted, valleys carved, and sediments deposited over immense time periods by the same physical forces and chemical reactions in evidence today.

Modern catastrophism—increasingly popular since the late 1970s—argues evidence that catastrophic forces can have a profound influence on shaping Earth. For example, modern catastrophic theory argues that large objects from space (Asteroids , Comets , etc.) periodically collide with Earth and that these collisions can have profound effects on both the geology and biology of Earth. Based on the extrapolation of experimental data and the observation of large-scale events (e.g., major volcanic eruptions ), scientists speculate that when these objects strike, they clog the atmosphere with sunlight-blocking dust and gases, ignite forest fires, and trigger volcanism. One hypothesis advances that a large asteroid impact lead to the extinction of dinosaurs roughly 65 million years ago.

See also Cambrian Period; Fossil record; Fossils and fossilization; Geologic time; Historical geology; Impact crater; K-T event; Origin of life; Orogeny; Plate tectonics; Precambrian; Torino scale

Catastrophism

In geology, catastrophism is the belief that Earth's features—including mountains, valleys, and lakes—were created suddenly as a result of great catastrophes, such as floods or earthquakes. This is the opposite of uniformitarianism, the view held by many present-day scientists that Earth's features developed gradually over long periods of time.

Catastrophism developed in the seventeenth and eighteenth centuries when tradition and even the law forced scientists to use the Bible as a scientific document. Theologians (religious scholars) of the time believed Earth was only about 6,000 years old (current scientific research estimates Earth to be 4.5 billion years old). Based on this thinking and the supernatural events described in the book of Genesis in the Bible, geologists concluded that fossils of ocean-dwelling organisms were found on mountain tops because of Noah's flood. The receding flood waters also carved valleys, pooled in lakes, and deposited huge boulders far from their sources.

Over the next 200 years, as geologists developed more scientific explanations for natural history, catastrophism was abandoned. Since the late 1970s, however, another form of catastrophism has arisen with the idea that large objects from space periodically collide with Earth, destroying life. Scientists speculate that when these objects strike, they clog the atmosphere with sunlight-blocking dust and gases. One theory holds that the most famous of these collisions killed off the dinosaurs roughly 65 million years ago.

[See also Uniformitarianism ]

catastrophism , in geology, the doctrine that at intervals in the earth's history all living things have been destroyed by cataclysms (e.g., floods or earthquakes) and replaced by an entirely different population. During these cataclysms the features of the earth's surface, such as mountains and valleys, were formed. The theory, popularly accepted from the earliest times, was attacked in the late 18th cent., notably by James Hutton, who may be regarded as the precursor of the opposite doctrine of uniformitarianism .

Catastrophism, however, was more easily correlated with religious doctrines (e.g., the Mosaic account of the Flood) and remained for some time the interpretation of the earth's history accepted by the great majority of geologists. It was systematized and defended by the Frenchman Georges Cuvier , whose position as the greatest geologist of his day easily overbore all opposition. In the 19th cent., it was attacked by George Poulett Scrope and especially by Sir Charles Lyell , under whose influence the contrary doctrine gradually became more popular. Recent theories of meteorite, asteroid, or comet impacts triggering mass extinctions can be interpreted as a revival of catastrophism.

Bibliography: See R. Huggett, Catastrophism: Asteroids, Comets, and Other Dynamic Events in Earth History (1998); T. Palmer, Controversy: Catastrophism and Evolution: The Ongoing Debate (1999).

Catastrophism

Catastrophism is a doctrine originally proposed by French zoologist Georges Cuvier (1769–1832) in 1810 to explain large geological and biological changes in the earth's history. The discovery of extinct animal and plant species under a coarse superficial deposit (diluvium) lead English geologist William Buckland (1784–1856) and others to suggest that this was caused by the biblical flood, which was then followed by the divine recreation of the animal and plant species living today (creationism). Scottish geologist Charles Lyell (1797–1875) rejected catastrophism and suggested that the same geological forces apparent today had always been at work on the earth, gradually changing the earth's surface and its biological species (gradualism). Today diluvium is attributed to glacial drift.

See also Creationism; Gradualism

arn o. gyldenholm

catastrophism A theory that associates past geological change with sudden, catastrophic happenings. Early geologists, including William Buckland (1784–1856), Cuvier, and Adam Sedgwick (1785–1873), claimed that catastrophism was a sound scientific theory. Although it met with considerable scorn in more recent times, many modern geologists acknowledge some degree of catastrophic change and so would describe themselves as ‘neocatastrophists’.

catastrophism A theory that associates past geological change with sudden, catastrophic happenings. Early geologists, including Buckland, Cuvier, and Sedgwick, claimed that catastrophism was a sound scientific theory. Although it met with considerable scorn in more recent times, many modern geologists would describe themselves as ‘neocatastrophists’.

catastrophism Theory that associates past geologic change with sudden, catastrophic happenings. Early geologists, including Cuvier, Buckland, and Sedgwick, claimed that catastrophism was a sound scientific theory. Although it met with considerable scorn in more recent times, many modern geologists would describe themselves as ‘neocatastrophists’.

ca·tas·tro·phism / kəˈtastrəˌfizəm/ n. • Geol. the theory that changes in the earth's crust during geological history have resulted chiefly from sudden violent and unusual events. Often contrasted with uniformitarianism. DERIVATIVES: ca·tas·tro·phist n. & adj.