Hans Cloos, German geologist and academic (d. 1951)
Hans Cloos (8 November 1885 – 26 September 1951) was a prominent German structural geologist.

Born in Magdeburg, Germany, Hans Cloos earned his doctorate at Freiburg in 1910, then worked in Indonesia and Namibia up until the start of First World War. During the war his geological skills were put to use along the western front.

Following the war, he began a study of plutons and their interior structure. In 1919 he became professor of geology at the University of Breslau. His younger brother, Ernst Cloos, who was born in 1898, would come to study geology at Breslau under his brother and later became a prominent geologist and professor at Johns Hopkins University.

In 1926 Cloos left Breslau to become professor of geology at the University of Bonn. He made additional geological trips to explore the Scandinavian region, England, and North America.

Professor Hans Cloos made pioneering studies of rock deformation, including granite tectonics. He employed scaled analogue models to study the physical mechanics of faulting, and examined how continents developed their structure. He was also noted for his artistic abilities, including music and draftsmanship.

Cloos died in Bonn, Germany in 1951.