GEOLOGY OF THE LAKE SUNAPEE AREA, NEW HAMPSHIRE

Several important features of the Acadian orogen in New Hampshire come together in the area surrounding Lake Sunapee, including plutons associated with all four groups of the NH Plutonic Series (NHPS), as well as a narrow septum of metasedimentary rocks potentially related to larger structures of the orogen. Mapping and other geological and geochemical studies in this area may help improve understanding of the relationships between structural development, magmatism and metamorphism during orogenic events. Results so far suggests that the Sunapee septum may include a significant shear zone, and that late brittle structures may be more important to interpreting the geology of this area than previously thought. In addition, a variety of cross-cutting relationships and igneous textures suggest an important role for the intrusion of magmas associated with the Spaulding Group of the NHPS. Our work may also have application to issues of ground water hydrology and water quality in the area.