MARINE, COASTAL AND LACUSTRINE GEOARCHAEOLOGY IN MAINE – AN INTERDISCIPLINARY RESEARCH PERSPECTIVE

The coast of Maine preserves Archaic through Ceramic and contact-period archaeological sites primarily in shell middens. However, scattered finds offshore provide evidence for submerged occupation sites. For more than 23 years we have developed a program of offshore and estuarine seismic reflection profiling, sidescan sonar, and underwater vibracoring to investigate submerged areas near known archaeological sites. Recently, ground-penetrating radar surveys have been applied to well-known sites such as the Glidden Midden in Damariscotta. The Maine relative sea-level curve is complex due to the compound effects of glacioisostasy and eustasy, but the rise in sea-level over the period 7000 cal yrs. BP to present has been relatively smooth (-20 m to present) and is well constrained by radiocarbon dates in salt marshes. Offshore geophysical and coring surveys such as Lazygut Island reveal high-energy shoreface with little likelihood of site preservation. Protected bay, thorofare and estuarine locations, on the other hand, preserve oyster bioherms, salt marsh and tidal flat environments stratigraphically. Recent work involves survey of an extensive oyster bioherm ca. 5000-3000 cal. yrs. BP at 9 to 5 m below present sea level in the central Damariscotta River estuary, an analogue to the source area for the Glidden Midden upstream. As oysters are locally extirpated due to climate change or pre-historic predation, this is an important setting to understand the natural resource. Despite tantalizing structural forms on seismic reflection profiles, no submerged anthropogenic sites have been found, only natural bioherms. Neverthleless, reconstruction of the resources and paleogeography further illuminate the natural environment available to the peoples using these marine resources. In a similar approach, we have studied Sebasticook Lake inland in Maine, a site of a submerged fishing weir at its inlet stream. Geophysical and coring surveys document lake-level changes including –9 m submerged shoreline terraces, prior to 7000 cal. yrs. BP, which correlate with incision of the inlet. The combination of geology, geophysics, and archaeology provides a richer understanding of the changes in pathways for anadromous and catadromous fish as lake-levels fluctuated, and the setting for human exploitation at the fish weir.