North-Central Section–40th Annual Meeting (20–21 April 2006)

Paper No. 5
Presentation Time: 1:20 PM-5:00 PM

SEDIMENTARY MAGNETIC RECORDS OF NATURAL AND ANTHROPOGENIC ENVIRONMENTAL CHANGE


PECK, John A., Department of Geology, University of Akron, University of Akron, Akron, OH 44325-4101, jpeck@uakron.edu

Environmental magnetism encompasses both paleomagnetic and rock magnetic measurements of natural samples. Paleomagnetic measurements have long been used to globally correlate and date sediments. Whereas, rock magnetic measurements of the concentration, grain size, and mineralogy of remanence-bearing magnetic minerals can provide insight on depositional systems because the nature of the accumulating magnetic minerals changes in response to varying sediment sources, transport mechanisms, weathering, and reductive diagenesis. In addition, wiggle matching of rock-magnetic records of environmental change to other dated environmental change records provides an important chronostratigaphic method.

An environmental magnetics laboratory was established at the University of Akron in 2001. Since then the lab has been used by numerous undergraduate and graduate students for both coursework and research. This poster presentation will summarize a variety of research projects undertaken at the University of Akron to show the widespread utility of the environmental magnetic method. Research project summaries include the application of rock-magnetic parameters as a proxy of heavy metal contamination in recent lake sediments. Rock magnetic parameters can provide important insight on sediment contamination issues because the pollution input is often highly magnetic. In addition, rock-magnetic records of natural environmental change aid in multiproxy reconstructions of environmental variability since deglaciation in Ohio. West African monsoon variability over the last 1 Ma is actively being studied at the University of Akron through the application of rock magnetic measurements of long drill cores from Lake Bosumtwi, Ghana.