MAGNETIC PARAMETER OF A SOIL AND LOESS SEQUENCE FROM ROSS COUNTY, OHIO, AND IT'S MEANING FOR PALEOCLIMATIC AND ENVIRONMENTAL CHANGE IN OHIO

The significance of this research was to determine if sediment of different depositional environments have different magnetic properties. Twenty samples were collected from a soil/loess sequence in Ross County, Ohio. The sediment consisted of a sequence of soil/loess/delta front sand/glacial lake clay, each representing different depositional environments. Magnetic parameters of concentration, grain size, and mineralogy were used to characterize the deposit of each environment. These magnetic parameters provide information on the processes operating in those environments. Due to pedogenic processes, the surface soil was expected to have the highest concentration of ferrimagnetic, superparamagnetic (SPM) grains in comparison to the other sediments. The results somewhat supported this expectation as the soils had ferrimagnetic concentration but not SPM as expected. Magnetite or maghemite were found to be the dominant magnetic minerals. The loess was magnetically high coercivity, coarse in size, and lower in concentration compared to the soil. The sand had ferrimagnetic concentration, coarse in size, and consisted of magnetite. The glacial clay had the lowest ferromagnetic concentration and finest in size.