Wanless was a well-known, respected geologist. He was a professor at the University of Illinois, a researcher, and a member of many organizations. Wanless was truly committed to his job. His research and publications not only continued but even increased until shortly before his death on June 3, 1970. He was 72 when he died. His final career effort was Our Changing Shorelines with Francis P. Shepard in 1971, it was published after his death.His most significant discovery was cyclothems. In 1932, Harold R. Wanless introduced the term cyclothem to describe the succession of sedimentary rock layers found in coal-bearing formations. The understanding of cyclothems remains an important tool for predicting the location of coal deposits and for defining the way sea levels change. Cyclothems are also important to the oil industry because the repeating sequences help in identifying the location of oil. It is this discovery that is displayed on a plaque at UIUC. There is also a portrait of Harold Wanless in a conference room named “Wanless Room” located in the geology building at UIUC that was named after Wanless. Geology students at U of I continue to learn about him and appreciate what he has done for the department. His papers can still be bought through the GSA.

Pictured above is the Wanless Room located within the Computing Applications Building at UIUC. There is a hallway also named after Wanless in the Natural History Building but it is currently under construction. Students use this room to study and work on projects.