TWENHOFEL, WILLIAM HENRY

(b. Covington, Kentucky, 16 April 1875; d. Atlantic, Georgia, 4 January 1957)

geology.

Twenhofel’s parents, Ernst A. H. J. Twenhofel and Helena Steuwer Twenhofel, of German ancestry, obtained a scant livelihood from cultivating a small farm near Covington. Twenhofel became acquainted at an early age with the rigors of farm life, for he had to help earn his own way. As a result of his work on the farm, he developed the physique and self-reliance that were to serve him well in later life when he carried on his geologic fieldwork in remote parts of North America. He also developed a keen interest in the outdoors, and especially in the reaction of plants and animals to their environment. His interest in nature continued throughout his life, and some of his most important scientific work concerned the formation, erosion, and preservation of soils, the action of plants and animals in producing and modifying sediments, and the ultimate deposition of the sediments, and their organic constituents to form sedimentary rocks.

In 1899 Twenhofel married his childhood sweetheart, Virgie Mae Stephens; they had three children, Lilian Helena, Helen Vivian, and William Stephens Twenhofel. Observant and ambitious, and keenly interested in understanding nature, the youthful Twenhofel taught in the local schools for six years until he could earn enough to enter National Normal University at nearby Lebanon, Kentucky, in 1902. Awarded his baccalaureate in 1904, he next taught science and mathematics in East Texas Normal College from 1904 to 1907. He entered Yale University at age thirty-two. While earning three degrees in geology, the B.A. in 1908, M.A. in 1910, and Ph.D. in 1912, he came under the influence of Charles Schuchert and Joseph Barrell. Twenhofel became a devoted follower of both men, finding in their teachings the stimulation to extend and diversify his interest in nature.

Using the college campus as a base of operations, and teaching as a means of livelihood, he began his geological career while still a graduate student at Yale by accepting an assistant professorship at the University of Kansas in 1910. In 1916 he moved on to the University of Wisconsin, where he joined Charles R. Van Hise, Charles K. Leith, Alexander N. Winchell, Warren J. Mead, and Armin K. Lobeck. These men, Twenhofel’s colleagues for the next thirty years, had a great effect on his scientific career.

When Twenhofel entered Yale, Schuchert was involved in a controversy concerning the Ordovician-Silurian boundary, and had decided that the solution lay in rocks of the Maritime Provinces of Canada. Twenhofel joined him on a field reconnaissance expedition in 1908: he later chose as the subject of his doctoral thesis the critical section on Anticosti Island, Quebec. Later in his career Twenhofel published important papers and reports on the Silurian section at Arisaig, Nova Scotia (1908), the Ordovician-Silurian strata of Anticosti Island (1927), the geology of the Mingan Islands of Quebec (1938), the Mid-Paleozoic rocks of Newfoundlands (1937, 1954) and the Baltic Provinces of Europe (1916), and the Silurian of Maine (1941). These important contributions, which brought him international recognition as an authority on Ordovician and Silurian stratigraphy and paleontology, demonstrated the transitional nature of the Ordovician-Silurian boundary in northeastern North America.

While carrying on his stratigraphic studies and teaching his classes at the University of Wisconsin, Twenhofel also continued his interest in sedimentation. While at the University of Kansas Twenhofel studied the remarkable Wreford and Foraker cherts and the Comanchean deposits of central Kansas . Soon after going to Wisconsin he became involved in a far-reaching controversy with Edward O. Ulrich concerning the stratigraphy of some Upper Cambrian formations of the Upper Mississippi Valley. Ulrich argued for the traditional layer-cake concept, placing the Mazomanie glauconitic beds above the Franconia formation. Twenhofel considered the two sequences essentially contemporaneous and laterally transitional, which was a novel and revolutionary interpretation for the time, but one that and his graduate students ultimately established by their detailed fieldwork. First as member and later as chairman of the Committee on Sedimentation of the National Research Council during the three decades from 1919 to 1949, he greatly stimulated research in sedimentation, along with T. Wayland Vaughan, Edward M. Kindle, and Arthur C. Trowbridge. His work as author of the monumental Treatise on Sedimentation (1926; 2nd ed., 1932) was internationally recognized.

when Raymond C. Moore launched the Journal of Sedimentary Petrology in 1931, Twenhofel became one of the associate editors. He served as editor from 1933 to 1946, guiding the struggling publication through difficult times to an established position among geologic journals. Twenhofel’s discussions of black shales stimulated renewed interest in those controversial rocks; his papers on ancient coral reefs and related subjects contributed to increased emphasis on paleoecology; and his early concerns over soil erosion and conservation were ahead of their time. Studies that he and his students made of the sediments of Wisconsin lakes greatly stimulated limnological research, and his reports on the black sands of the Oregon beaches called attentio to those deposits of winnowed sands as possible sources of certain valuable minerals, as magnetite and ilmenite.

More than anyone else in his time, Twenhofel led and promoted the study of sedimentation as a branch of geology, and the present great strength and importance of the subject are largely the result of his leadership as investigator, teacher, author, and editor.

BIBLIOGRAPHY

I. Original Works. Twenhofe’s scientific writings cover a broad range of geologic subjects and reveal an unusual ability to organize and interpret large amounts of descriptive matter. He wrote more than seventy-five important articles and reports, and five widely used text-books, all on some aspect of sedimentation, stratigraphy, and paleontology. His writings are listed in the Bibliographies of North American Geology, published as Bulletins of the United States Geological Survey. His five major works are Treatise on Sedimentation (Baltimore, 1926; 2nd ed., 1932); Invertebrate Paleontology, with R. R. Shrock (New York, 1935); Principles of Sedimentation, (New York, 1939) : Methods of Study of Sediments, with S. A. Tyler (New York, 1941); and R. R. Shrock and W. H. Twenhofel, Principles of Invertebrate Paleontology (New York, 1953).

Major reports dealing with both stratigraphy and paleontology include“The Geology and invertebrate Paleontology of the Comanchean and ‘Dakota’ Formations of Kansas,”Kansas State Geological Survey, bulletin 9 (1924); et al.,“Geology of Anticosti Island,”Canadian Geological Survey, memoir 54 (1927);“The Building of Kentucky,”Kentucky Geological Survey, ser. 6, 37 (1931); et al.,“Geology and Paleontology of Mingan Islands, Quebec. . .,”Geological Society of America, Special paper 11 (1938);“Soil, the Most Valuable Mineral Resource; Its Origin, Destruction, and Preservation,”Oregon Department of Geology and Mineral Industries Bulletin, 26 (1944).

II. Secondary Literature. Additional biogrpahical and bibliographical data are included in R. R. Shrock,“William Henry Twenhofel—Honorary Member,”in Bulletin of the American Association of Petroleum Geologists, 31 (1947), 835-840;“Memorial William Henry Twenhofel (1875-1957),”in Journal of Sedimentary Petrology, 27 (1957), 203; “William Henry Twenhofel (1875–1957),” in Bulletin of the American Association of Petroleum Geologists, 41 (1957), 978-980; C. O. Dunbar,“Memorial to William Henry Twenhofel (1875-1957),”in Proceedings. Geological Society of America; annual report for 1960 (1962), 151-156.

Robert R. Shrock

Twenhofel, William Henry (1875–1957) An American geologist, Twenhofel was a professor at the University of Wisconsin. He made studies of American Palaeozoic sediments, but is best known for his work on the processes of sedimentation, described in his book Treatise on Sedimentation (1926, 1932).