My Research Interests...
The essence of my research is understanding how and why landscapes change over time. There are many "buzz words" used in the literature to describe such a lofty goal, but more popular ones include "landscape evolution", "paleoenvironmental record", "late Quaternary environments", "paleoclimatic implications", and "deglacial history of". The fundamental approach for such a large undertaking is to study the processes that work at the Earth's surface, and then use these modern analogues to make interpretations about past processes. Identifying the processes that worked thousands or tens of thousands of years ago under different climatic conditions involves multiple disciplines, including sedimentology, hydrogeology, pedology (study of soils and paleosols), paleolimnology, palenology, and even structural geology. Geomorphology is anything but mundane!
Currently I am working on several aspects of the late Pleistocene and Holocene evolution of the lower Ohio River Valley, which is the focus of my PhD research. The lower Ohio River Valley is interesting for a number of reasons. First, it was a major drainage outlet for the Laurentide Ice Sheet. The bedrock valley of the Ohio RIver was deep prior to glaciation, so there was plenty of accommodation space for glaciofluvial sediments, so deposits are thick in this part of the valley. These sediments include outwash, multiple loess sheets with paleosols, and complex deltaic and splay deposits that lie within and are interfingered with slackwater lake deposits. I even found a buried beach sand in one core.
The thick and diverse sediments In the lower Ohio Valley have implications for the seismic hazard of the region. This area is seismically active. In the past 20 years it has produced 4 earthquakes larger than M 5.0., and the sedimetns are susceptible to seismically induced grond failure (liquefaction) and amplification of shaking. I have found paleoliquefaction features that indicate there have been major earthquakes in the past. I have also found some compelling evidence that suggests neotectonic deformation diverted the course of the Ohio River at least once during the Holocene. And perhaps most the tantalizing possibility is, because this region lies between the Wabash Valley Seismic Zone and the New Madrid Seismic Zone, and the Ohio River from one zone and through the other, research here may one day reveal if and how the Wabash Valley and New Madrid Seismic Zones are related.
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