Mr. Jensen studied physics at the University of Chicago, graduating in 1935. He became a commercial photographer and founded the photography department at Procter & Gamble.
During World War II, Mr. Jensen worked for the Navy as part of a team developing anti-submarine technologies. He was a co-inventor of the magnetometer, still used today for anti-submarine patrols. During the war, he recognized the magnetometer's potential for exploring for oil and minerals.
In 1946, Mr. Jensen began working at Aero Service Corp., one of the world's oldest land surveying companies. In 1947, he employed the magnetometer commercially on a large-scale survey conducted in the waters off the Bahamas for six of the world's major oil companies.
Several months later, Mr. Jensen directed an airborne mineral survey, in eastern Pennsylvania for the Bethlehem Steel Co., which uncovered a major and previously unknown iron deposit, the Morgantown Mine, and firmly established the airborne magnetometer as an important new tool for the mining industry.
During the next four decades, under Mr. Jensen's direction, Aero Service Corp. surveyed for minerals and petroleum on every continent except Antarctica. Major surveys of the North Sea, the North Slope of Alaska, Venezuela, Australia and throughout the Middle East and Africa resulted in the development of some of the world's most significant oil fields and the discovery of mineral deposits.
In the 1970s, he turned his attention to the use of radar aboard aircraft to produce images of large areas of the earth's surface. In partnership with Goodyear Aerospace Corp., Mr. Jensen was instrumental in developing this former military technology, called side-looking airborne radar.
Mr. Jensen was a prolific inventor throughout his life and held 17 U.S. and two foreign patents.
He loved to travel and collected ethnic art objects and furniture. Mr. Jensen and his first wife, Jeanne Darack Jensen, had an avid interest in art and often opened their home to artists.
His son, Peter, said that growing up with his father was like being exposed to the whole world.
"As children, the thing that was most wonderful was that he brought the world into the family through his travel," Peter Jensen said. "We never knew who would be coming to dinner or what language would be spoken."
Mr. Jensen was a frequent contributor to scientific and technical journals, and wrote two articles for Scientific American. He was a former vice president of Litton Industries.
He is survived by his wife, Claire Forest; his five children, Peter,
Judith, Kristina Creighton, Lauren and Jeannie; five grandchildren, and his brother, John.
A memorial service is planned but has not been scheduled.