Rates of Regional Denudation in the United States

Data, in large part collected since World War II, allow a recalculation of the rates of regional erosion in the United States. These data indicate a rate of denudation for the United States as a whole of 2.4 in./1000 years, or about twice that of older estimates. The most rapid rate, 6.5 in./1000 years, is recorded from the Colorado drainage. The slowest rate, 1.5 in./1000 years, is found in the Columbia basin. Other drainage areas and their rates are the Pacific slopes, California, 3.6 in/1000 years; the western Gulf of Mexico, 2.1 in./1000 years; the Mississippi River watershed, 2.0 in/1000 years; the South Atlantic and the eastern Gulf of Mexico, 1.6 in/1000 years, and the North Atlantic, 1.9 in/1000 years.