QUATERNARY SUPERFLOODS

There is a long history of controversy over the role of cataclysmic flooding in the origins of Quaternary landscapes and sedimentary sequences. A logically flawed doctrine of uniformitarianism greatly impeded scientific progress on this topic, and the pernicious consequences of flawed uniformitarian reasoning persist to the present day. During the later part of the 20th century there was a renaissance in cataclysmic flood studies, beginning with the controversy over the origin of the Channeled Scabland in the northwestern U.S. Following the resolution of that controversy, more recent discoveries revealed that cataclysmic flooding impacted the Quaternary margins the great ice sheets and the margins of large mountain glaciers in North America and Eurasia. Numerous spillways connected ice-marginal lakes and constituted flood-generated rivers in central North America and central Asia. The discharges of these temporary rivers greatly exceeded those of any modern river. Many of the largest floods produced flows equivalent in magnitude to those of ocean currents. Thus, they had immense capability to stimulate very rapid, short-term effects on Quaternary climate. They also greatly altered drainage evolution and the planetary patterns of water and sediment fluxes to the oceans.