We are interested in the response of shorelines, and the people who live on them, to sea-level changes. The greatest changes in sea level are associated with glacial growth and disintegration. Where we have worked in Maine and Ireland, however, isostatic land-level changes caused by glacial loading and unloading, have dominated the regional sea-level signal. We have also worked in lake environments where lake-level changes were caused by tilting associated with isostasy. Much of the work we do involves using geophysical tools like side scan sonar, seismic reflection and ground-penetrating radar to remotely sense the underwater and underground environments.
Faculty
Daniel F. Belknap, Joseph T. Kelley.
Research
We have a project beginning in Northern Ireland this spring with colleagues at the University of Ulster, Northern Ireland. We will be collecting cores offshore Giants Causeway to follow up on geophysical work published last year regarding the complex sea-level history of the area (Cooper et al., 2003).
We are also studying the lowstand of sea level in the Gulf of Maine. We plan to collect underwater vibracores this summer off Saco Bay, Maine where earlier studies have indicated lowstand deposits (Kelley et al., 2003).
We are interested in land/sea connections as well. Drainage changes associated with land-level adjustments have been profound in Maine and in other glaciated areas. Our student, Greg Balco showed that Maine's largest lake has transferred its drainage as a result of isostatic adjustments in the Holocene (Balco et al., 1998). We are now investigating the offshore impact of those changes in drainage (Belknap et al., in press).
In the course of seaflor mapping in Maine (Barnhardt et al., 1996; Kelley et al., 1998), we have become interested in methane escape from the seabed (Kelley et al., 1994; Barnhardt and Kelley, 1996; Barnhardt et al., 1997; Gontz et al., 2003). We suspect that the source of carbon for the gas accumulations is terrestrial or estuarine from time of lower-than-present seavel.