Mark Gordon Inghram (November 13, 1919 – September 29, 2003) was an American physicist.
He worked in the Manhattan Project during World War II and at Argonne National Laboratories from 1945 to 1947.
He began teaching at the University of Chicago as an instructor in 1947 and remained there until his retirement in 1985.
Patterson, Tilton and Inghram assumed that iron meteorites, which contain lead but virtually no uranium, formed at the same time as the Earth.
Patterson, Tilton and Inghram did this and found that the Earth was approximately 4.5 billion years old.