Sandidge, John Roy (1897–1976)

By: Samuel P. Ellison, Jr.

Type: Biography

Published: June 1, 1995

John Roy Sandidge, micropaleontologist, was born on December 15, 1897, to John Madison and Melanie Walter (Loucks) Sandidge in Fort Worth, Texas. He attended public school in Fort Worth and Wichita Falls and was granted his bachelor's degree by Texas Christian University in 1920. He earned a second bachelor's degree at TCU in 1921 and a master's degree in 1922 at Vanderbilt University. He then taught for two years at Erskine College in South Carolina. He entered Johns Hopkins University in 1924. During his graduate work there, he worked as summer assistant to the Texas Bureau of Economic Geology and the United States Geological Survey. He taught geology at Birmingham-Southern College in 1926–27 and received his Ph.D. at Johns Hopkins in 1928. Sandidge worked as a consultant for the Sinclair Exploration Company on foreign foraminifera samples. He also worked for a time in 1927 in the Joseph Cushman Foraminifera Laboratory near Boston, Massachusetts. He joined the faculty of Princeton University and served as an instructor for two years and as an assistant professor for three years. Sandidge married Ida Thompson, a librarian at Johns Hopkins, in March 1929. When the depression years ended his early teaching, he joined Magnolia Petroleum Company (later Mobil Oil Company) in San Antonio in 1933. At first he worked in micropaleontology but progressively turned to many other phases of exploration geology. His main work was the rejuvenation of the Luling oilfield, where he instigated additional drilling and treatment of old wells that resulted in record production in 1954. He continued to advance in his work and became Mobil's supervisor of exploration for the South Texas area. In 1960, after retiring from Mobil, he returned to teaching geology. He served as chairman of the Department of Earth Sciences at San Antonio College from 1960 to 1976. His leadership in professional societies included a fellowship in the Geological Society of America, the vice presidency (1940) and presidency (1946) of the Society of Economic Paleontologists and Mineralogists, and honorary life membership in the South Texas Geological Society (awarded in 1964). Sandidge died on November 13, 1976, in San Antonio, and was survived by his wife.

Samuel V. Ellison, Jr., "Memorial to John Roy Sandidge," Geological Society of America Memorials 8 (1978). San Antonio Express, November 15, 1976.

The following, adapted from the Chicago Manual of Style, 15th edition, is the preferred citation for this entry.

Samuel P. Ellison, Jr., “Sandidge, John Roy,” Handbook of Texas Online, accessed August 19, 2022,

Published by the Texas State Historical Association.

June 1, 1995

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