Career
In 1913, senior lecturer at the University of Oslo in 1914, and Professor of geology there from 1920 to 1956. Holtedahl was among the last of a generation of geologists that mastered the subject in all its breadth. He delivered a significant contribution, not only in Norway but also for large areas of the Arctic and Antarctic.
His first geological work dealt with the Oslo Rift in kambrosilur, and he was part of the 1909-1911 expeditions to Svalbard, 1914-1917 he explored Lapland Geology, 1918, he worked at Bear Island.
In 1921 he led a Norwegian expedition to Novaya Zemlya and was 1927-1928 with the Lars Christensen"s Antarctic expeditions, from these expeditions he edited the scientific results. He was Doctoral advisor of Professor Bjørn G. Andersen, and was the main initiator of his Quaternary geological works.
Olaf Holtedahl was the father of Professor of geology Hans Holtedahl (1917–2001).