Thomas Henry Clark, Ph.D., FRSC (December 3, 1893 – April 28, 1996)[1] was a Canadian geologist who is considered to have been one of the nation's top scientists of the 20th century.
In 1924, Clark moved to Montreal to take an assistant professor position in the Geology Department at McGill University.
In 1926, Clark began a major project to map the geology of the Quebec Appalachian Mountains along the U.S. border in the Eastern Townships.
By the late 1960s, Montreal's development and various projects along the St. Lawrence seaway necessitated a revision of Clark's previous geological studies of the area.
This time the work involved capturing information from the many oil and gas and engineering projects, as well as acquiring core samples from excavations for future research.