The Sangamon Paleosol in Brown County, Kansas

Abstract

A previously unstudied Sangamon paleosol was examined in Brown County, Kansas, to determine its characteristics and geographic distribution. The paleosol is buried by Wisconsinan loesses on uplands, where it is enriched in base elements eluviated from the loess. On shoulder slopes the soil is exhumed and leached. Stratigraphic evidence suggests that the soil is developed in thin Loveland loess over pre-Illinoian till beneath uplands while downslope, in exhumed locations, the Loveland member has been eroded and the truncated paleosol is formed only in till. The paleosol appears to have been a very strongly developed Ultisol or Mollisol at the time of burial. Evidence of the Sangamonian interglacial stage is well preserved in Kansas by the extensive and widespread occurrence of the Sangamon paleosol or geosol, as used by Morrison (1965). Although the type area for this paleosol is in Illinois (Follmer, 1978), its presence has been documented from Indiana (Hall, 1973; Ruhe et al., 1974; Ruhe and Olson, 1980) through Illinois (Follmer, 1979; Bushue et al., 1974), Nebraska (Schultz and Stout, 1945; Thorp et al., 1951), Iowa (Simonson, 1941; Ruhe, 1956, 1969), and Kansas (Frye and Leonard, 1952). In Kansas, the paleosol is best developed in the area adjacent to the Missouri River valley, as at the Loveland type section (Frye and Leonard, 1952) or the now destroyed exposure near Iowa Point (Frye and Leonard, 1949), both in Doniphan County. Research by Bayne et al. (1971), Caspall (1970), and Tien (1968) on the Sangamon soil in Doniphan County constitute additional studies of the paleosol in northeastern Kansas. Examinations of exposures of Quaternary deposits, coupled with numerous upland soil cores, have resulted in new data on the Sangamon soil in Brown County. Previous research on this paleosol had been mainly confined to adjacent Doniphan County. The purpose of this report is to document the presence of numerous exposures, many recent, of the Sangamon soil in This content downloaded from 207.46.13.124 on Wed, 22 Jun 2016 05:15:48 UTC All use subject to http://about.jstor.org/terms VOLUME 89, NUMBERS 3-4 153 Brown County, and to describe the characteristics and geographic extent of this paleosol. Data and results are summarized from Schaetzl (1983).