GEOARCHAEOLOGY OF THE ANDROSCOGGIN RIVER IN WESTERN MAINE

Archaeological excavations conducted over a thirty-year period focus on the deeply stratified Holocene deposits of the river terraces.

The Holocene archaeological deposits in the Rumford Falls empoundment are stratified above a glacial lake of the late Pleistocene. Deep, stratified deposits are radiocarbon dated from 9,500 B.P. to 350 B.P. at select locations. The geological analysis at 10 sites included stratigraphic profiles with grain-size analysis at 5 to 10 cm increments to characterize fluvial activities associate with the deposition within prehistoric sites. The analysis of geochemistry is with a Niton portable XRF unit and is utilized to characterize integrity and preservation quality of stratigraphic units within site and between site locations.

The excavation and stratigraphy in the Rumford Falls empoundment are compared to other radiocarbon dated archaeological and geological studies upriver and downriver to Merrymeeting Bay. Further comparisons are extended to the Saco and Presumpscot Rivers to the west and to the Kennebec River to the east. The Rumford Falls sites document recent (past 1,000 years) flood deposits that are discrete and well-defined. Several of these events may represent broad, regional events in the Late Ceramic Period.