Hollis Dow Hedberg (May 29, 1903 – August 14, 1988; nickname: "El Doctor Hedberg") was an American geologist specializing in petroleum exploration. His contribution to stratigraphic classification of rocks and procedures is a monumental work which received universal acceptance. The firm he worked for, the Gulf Oil Corporation in Venezuela, trusted his findings and explored what had until then been uncharted territory. As a result, they reaped huge benefits from their petroleum findings.Hedberg taught at Princeton University from 1959 until his retirement in 1971. He was awarded the Mary Clark Thompson Medal by the National Academy of Sciences in 1973. In 1975 he was awarded the Wollaston Medal by the Geological Society of London. Hedberg won the Sidney Powers Memorial Award in 1963.