Geomorphic implications of Pre-Wisconsin soils on the White River Plateau erosion surface of northwestern Colorado

Abstract

The White River Plateau erosion surface (Miocene-Pliocene) at an elevation of approximately 2850 m (9500 ft) is dominated by weakly developed Holocene soils which commonly possess simple A-C horizonation. However, Pre-Wisconsin soils occur on the surface in isolated areas at both high and low topographic sites, most notably in Triangle Park. These Pre-Wisconsin soils consist of composite, polygenetic profiles having truncated, clayey subsoils which are overlain by stone or pebble lines, colluvium, soil creep, and probable local eolian deposits Truncation of the paleosols preceded development of the Holocene soils, which have formed on bedrock surfaces and have been superposed on the truncated, buried paleosols Soil distribution and character, in relation to structure of bedrock on the erosion surface, indicate that the surface as it now exists is structurally controlled and has a topography generated in late Tertiary to Pre-Wisconsin time.