Cushman, Joseph Augustine

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Cushman, Joseph Augustine

(b. Bridgewater, Massachusetts, 31 January 1881; d. Sharon, Massachusetts, 16 April 1949)

micropaleontology.

Cushman pioneered the use of Foraminifera(an order of microscopic shelled Protozoa)in the search for petroleum. His work stimulated other investigators and initiated a period of unprecedented study of the order.

The son of Darius and Jane Frances Fuller Pratt Cushman, he grew up in the small college town of Bridgewater, where his father sold and repaired shoes. Cushman’s early schooling was in Bridgewater, then at Harvard College, where cryptogamic botany was his initial interest. Because of the influence of Robert Tracy Jackson, however, he changed to paleontology. After graduation in 1903 he became a curator at the Museum of the Boston Society of Natural History and spent some summers on botanical collecting trips.

Cushman spent the summers of 1904 and 1905 at the U.S. Fish Commission station at Woods Hole, where Mary J. Rathbun urged him to study rich collections of Foraminifera recently obtained by the commission’s steamer Albatross. Thus began his systematic identification and description of Holocene Foraminifera. When he started his studies, Foraminifera were regarded as primitive, highly variable organism having geologic ranges from Cambrian to Holocene and having no value other than as curiosities.

Cushman began his work within the framework of Brady’s classification of ten families, which was based on morphology of adult forms. Within a short time he began to formulate a radically different classification that resulted from application of Haeckel’s law of recapitulation, in which development of the individual repeats phylogenetic development of the species. Cushman’s classification, consisting of forty–five families, was first published in outline form in 1927 and was republished the next year in a textbook, Foraminifera, Their Classification and Economic Use, which went through four editions.

Cushman was employed in 1912 by the U. S. Geological Survey as a specialist on Foraminifera and in 1914 made his first diffident attempt at age determination of well samples by Foraminifera (Stephenson, pp. 79–81). By 1918 he was confident enough about Foraminifera to use species as indicators of formations and to include interpretations of their paleoecology. In 1921 he stated that Foraminifera “faunas of the various members of these formations [in the American Gulf Coast plain] are easily recognizable.” By that time some economic paleontologists had independently realized the truth of this statement and were using Forminifera as stratigraphic tools.

In January 1923, Cushman was employed in Mexico by the Marland Oil Company to apply his knowledge of Foraminifera in correlating surface rock outcrops and drill holes. He returned in March to Sharon, Massachusetts, where he build a private laboratory for consulting work. He continued consulting for another year, then retired from commercial work to devote all his time to research. In 1925 Cushman stated his privately financed journal, Contributions From the Cushman Laboratory for Foraminiferal Research, to contain the numerous papers that came from his prolific pen. He offered his services as teacher without stipend for students from Harvard and Radcliffe and also accepted private students. In 1927 and 1932 he visited Europe to examine type specimens and to collect from type localities.

In the 1920’s Cushman’s interest expanded from formal description of Foraminifera in the Albatross collections to include systematic descriptions of faunas from geologic formations and, in the 1930’s, monographic studies of families and genera. In the 1940’s Cushman began to realize the potential of planktonic species as a means of stratigraphic zonation, and worldwide zonation by planktonic Forminifera found wide acceptance shortly after Cushman’s death. As his work on Holocene faunas increasingly provided a basis for comparison, paleoecologic interpretation became part of Cushman’s work on fossil faunas. During nearly fifty years he produced more than 550 papers. His extensive collections were bequeathed to the U. S. National Museum, where they constitute the world’s largest collection of Foraminifera.

During Cushman’s lifetime the study of Foraminifera progressed from being an obscure hobby of some few dozen investigators, mostly European, to become a major factor in the oil industry, involving thousands of investigators and large sums of money. Cushman evaluated his own success as being “due to the very thing for which I have been criticized… the tendency to split species” (Schuchert, p.549). His classification, now largely superseded by more detailed ones, nevertheless constituted the basic structure for these later ones. Although additional microfossils and other methods are now used in oil exploration, Foraminifera are still an invaluable tool in biostratigraphy and paleoecology.

BIBLIOGRAPHY

I. Original Works. A complete bibliography of Cushman’s works is in Todd et al. (see below), pp. 40–68. Cushman’s writings include Some Pliocene and Miocene Foraminifera of the Coastal Plain of the United States, U. S. Geological Survey Bulletin no. 676 (Washington, D. C., 1918); “Use of Foraminifera in Determining Underground Structure Especially in Petroleum Mining,” in Bulletin of the Geological Society of America, 33 (1921), 145–146, an abstract; “An Outline of a Re-classifications of the Foraminifera,” in Contributions From the Cushman Laboratory for Foraminiferal Research3 pt. 1 (1927), 1–105, pls, 1–21; and Foraminifera, Their Classification and Economic Use, Cushman Laboratory for Foraminiferal Research, special publication no. 1(Sharon, Mass., 1928).

II. Secondary Literature. Additional information can be found in the following (listed chronologically): L. W. Stephenson, A Deep Well at Charleston, South Carolina, U. S. Geological Survey, professional paper 90–H (Washington, D. C., 1914); T. W. Vaughan, “On the Relative Value of Species of Smaller Foraminifera for the Recognition of Stratigraphic Zones,” in Bulletin of the American Association of Petroleum Geologists, 7, no. 5 (1923), 517–531; Charles Schuchert, “The Value of Microfossils in Petroleum Exploration,” ibid., 8 no. 5 (1924), 539–553; J. A. Waters, “Joseph Augustine Cushman, 1881–1949,” ibid., 33, no.8 (1949), 1457–1468; Ruth Todd et al., Memorial Volume (Sharon, Mass., 1950). final publication from the Cushman Laboratory for Foraminiferal Research; and L. G. Henbest, “Joseph Augustine Cushman and the Contemporary Epoch in Micropaleontology,” in Geological Society of America Proceedings, Annual Report for 1951 (July 1952), 95–101.

Ruth Todd

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