Geology topics
Research about Maine
Source-linked reports with geographic coverage including Maine.
The geology of the Perry Basin in southeastern Maine
The geologic examination of the Perry district, in southeastern Maine, was undertaken at the request of the Survey Commission of the State of Maine. During the 1902-3 session of the Maine legislature an effort was made by petitioners resident in Washington County to obtain from the State an appropriation of $10,000 for coal exploration. The resolve proposed contained a ,proviso necessitating an additional contribution of $5,000 by individuals or corporations interested. The $15,000 thus procured was to be expended in drilling for coal at the most promising localities. The resolve failed to pass, but the Maine Survey Commission decided that the same results could be accomplished by the expenditure of a small portion of the general appropriation for geologic work in cooperation with the United States Geological Survey.
Integrated geophysical characterization of the Winthrop Landfill Southern Flow Path, Winthrop, Maine
The U.S. Geological Survey (USGS), in cooperation with United Technologies Corporation, used an integrated suite of borehole, surface, and water-borne geophysical methods near the site of the former Winthrop Landfill, Winthrop, Maine, to investigate the hydrogeology controlling the transport of leachate from the landfill to nearby Annabessacook Lake. During the fall of 2000 and summer of 2001, the USGS conducted borehole electromagnetic (EM) induction and gamma logging, and inductive terrain-conductivity, two-dimensional (2D) resistivity, continuous seismic reflection, and magnetic surveys. The objectives of this integrated geophysical study were to provide constraints on the location and extent of the southern flow path(s) of contamination from the landfill to the lake; identify shoreline seep geophysical signatures; identify potentially hidden seeps in the lake; and determine depth to bedrock below Annabessacook Lake in the study area. Interpretation of surface 2D resistivity, magnetic, and inductive terrain-conductivity data and borehole EM logs delineates an electrically conductive anomaly consistent with a leachate plume moving from the current landfill boundary southward through the overburden to the shores of Annabessacook Lake. Surface and borehole geophysical data collected south and southeast of the landfill indicate the presence of discrete, shallow conductive anomalies at the southeastern edge of the landfill and near the lakeshore. The conductive anomalies appear at increasing depths closer to the lake. Magnetic anomalies offshore confirm the presence of iron-rich landfill leachate discharging into the lake south of the landfill. High-resolution swept-frequency seismic data used to map sediment and grain size distribution in the lake sub-bottom along the shoreline identified sediment-infilled bedrock lows that may act as conduits for contaminant migration.