Evidence of Multiple Stades in the Lower Pleistocene of Northeastern Kansas

Abstract

Nebraskan and Kansan glacial and glacio-fluvial deposits in Kansas occur only in the northeastern part of Kansas. generalized four-fold history of continental glaciation has long been accepted in the United States. Generally the highest till was correlated with the youngest glaciation and an underlying till correlated with the next youngest glaciation. In areas where only early Pleistocene glaciations occurred, this same method of correlation was practiced. Recognition of a more complex system of advances and retreats of ice in the Wisconsinan Stage lead to the adoption of substage or stade division of this stage. Each of the glacial stages is separated from the succeeding glacial stage by an interglacial stage. This period was one of relative stability under comparatively warm conditions during which extensive interglacial soils were developed in the periglacial regions as well as in the glaciated regions. Buried profiles of weathering, or fossil soils, are perhaps the most usable criteria for stratigraphic correlation and classification of the Pleistocene sediments in Kansas. The top of a buried soil is unmistakably an unconformity, and where deep well-developed soil profiles occur, a significant interval of nondeposition and only slight erosion is indicated. Interpretation of the soils within the Pleistocene sequence involves the evaluation of the soil horizons as interglacial or interstadial and may lead to errors in correlation. The strength of soil development is believed to be the most important factor in this interpretation. Pronounced zones of clay enrichment in the B horizon, considerable depth of leaching, great depth of oxidation, and significant thicknesses of secondary lime accumulation are believed to be more important and better indicators of interglacial nature of soils than the thickness of the humic A horizon which often has been removed by erosion or scour. Frye and Leonard (1949, 1952) described the exposure of two tills in a quarry in the Missouri River Bluff near Iowa Point in northeastern Doniphan County. well-developed soil on the lower till was indicative of a long period of weathering prior to deposition of the upper till.