@proceedings {280,
	title = {Deep geothermal potential of New England granitoids; the Fall River Pluton, southeastern Massachusetts},
	volume = {43},
	year = {2011},
	note = {Accession Number: 2012-031359; Conference Name: Geological Society of America, Northeastern Section, 46th annual meeting; Geological Society of America, North-Central Section, 45th annual meeting; Pittsburgh, PA, United States; Conference Date: 20110320; Language: English; Coden: GAAPBC; Collation: 1; Collation: 63; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 201217; Monograph Title: Geological Society of America, Northeastern Section, 46th annual meeting; Geological Society of America, North-Central Section, 45th annual meeting; Monograph Author(s): Anonymous; Reviewed Item: Analytic},
	month = {2011/03/01/},
	pages = {63 - 63},
	publisher = {Geological Society of America (GSA) : Boulder, CO, United States},
	address = {United States},
	abstract = {Devonian-aged plutonic rocks that are interpreted to be part of the Fall River pluton, along the southern edge of the Narragansett Basin, appear to have potential as a source of deep geothermal energy. The Narragansett Basin covers a approximately 1500 Km (super 2) area in southern Massachusetts and is dominated by complexly deformed and metamorphosed, Pennsylvanian-aged, fluvial and alluvial deposits. A northeast-striking series of brittle faults and discrete shear zones define the southern margin of the basin. Preliminary modeling of igneous and gneissic fabrics from outcrops along the southern edge of the basin show that the granite dips predominantly north, northeast. This pattern suggests that granitoids along the southern edge of the basin continue beneath the Narragansett Basin and correlate with granitoids exposed to the north. Regional joint sets in the Fall River pluton can be grouped into three dominant clusters at 350 degrees , 90 degrees , and 250 degrees based upon 86 field measurements. Low-angle sheeting joints are also common and suggest interconnected fracture networks at depth. Preliminary geochemistry from the Fall River pluton suggests that feldspars and accessory minerals contain the appropriate concentrations of heat producing elements, primarily U, Th, and K, to be a reasonable geothermal resource. K (sub 2) O values range from 2.4 to 5.0 weight percent. U and Th values (in ppm) range from 0.9 to 6.2 and 2.9 to 30.1 respectively. Assuming a relatively consistent composition at depth, a density of 2.6 kg/m (super 3) , and a thermal conductivity of 2.9 W/m degrees C, initial temperature modeling suggests average temperatures of 81 degrees C at depths of 5 kilometers and 93 degrees C at depths of 6 kilometers. Temperature estimates increase to approximately 150 degrees C and approximately 170 degrees C respectively when a two kilometer thick sediment package is modeled overlying the granitoids. The goal of current and future work is to improve assumptions about compositional uniformity as well as the regional position of granitoids at depth. At the conclusion of this work we hope to develop a protocol for studying geothermal potential of buried granitoids in New England in the absence of reliable drill-hole data. Preliminary estimates from this project suggest that basins underlain by granitoids of compositions similar to that of the Fall River pluton have reasonable potential as a deep geothermal resource.},
	keywords = {$\#$StaffPubs, depth, Economic geology, geology of energy sources 29A, Fall River Pluton, geochemistry, geothermal energy, gneisses, granites, Igneous and metamorphic petrology 05A, igneous rocks, intrusions, massachusetts, metamorphic rocks, plutonic rocks, plutons, southeastern Massachusetts, United States},
	isbn = {00167592},
	url = {https://gsa.confex.com/gsa/2011NE/finalprogram/abstract_185900.htm},
	author = {Goodhue, Nathaniel and Koteas, G. Christopher and John Michael Rhodes and Stephen B Mabee}
}
@proceedings {284,
	title = {Evidence for arsenic-mineralization in granitic basement rocks, Ayer Granodiorite, northeastern Massachusetts},
	volume = {42},
	year = {2010},
	note = {Accession Number: 2010-100047; Conference Name: Geological Society of America, Northeastern Section, 45th annual meeting; Geological Society of America, Southeastern Section, 59th annual meeting; Baltimore, MD, United States; Conference Date: 20100314; Language: English; Coordinates: N420800N424400W0710200W0715300; Coden: GAAPBC; Collation: 1; Collation: 160; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 201052; Monograph Title: Geological Society of America, Northeastern Section, 45th annual meeting; Geological Society of America, Southeastern Section, 59th annual meeting; joint meeting, abstracts volume; Monograph Author(s): Anonymous; Reviewed Item: Analytic},
	month = {2010/03/01/},
	pages = {160 - 160},
	publisher = {Geological Society of America (GSA) : Boulder, CO, United States},
	address = {United States},
	abstract = {Core samples of the Ayer Granodiorite along the eastern margin of the Merrimack Belt in northeastern Massachusetts host a series of sulfide and oxide phases that resulted from interaction with sulfide-bearing meta-sedimentary host rocks. Euhedral arsenopyrite grains are found with ilmenite, apatite, and REE phosphates in zones that generally mimic the intersection between a gneissic fabric and a relict magmatic foliation. Arsenopyrite crystals are typically elongate with this lineation. Euhedral to subhedral pyrite crystals have also been observed, but are localized to areas without As-bearing phases. Micro-fractures that parallel either a steep NW-striking joint set or gently-dipping sheeting joints are commonly filled with interwoven calcite cements and As-bearing Fe-oxides. Surface coatings of major fracture sets are also characterized by Fe-As-rich rinds that host micron-scale sub-angular particles of quartz, feldspars, and phyllosilicates. Where micro-fractures are most concentrated, sulfide-bearing minerals are less common; however, subhedral to anhedral arsenopyrite grains do occur along some open micro-fractures. These crystals preserve lobate grain boundaries and are associated with As-bearing Fe-oxide-rich coatings along adjacent fractures. The presence of 1) pyrite, 2) arsenopyrite associated with phosphates, and 3) As-bearing fracture coatings suggests multiple stages of mineralization. We propose that intrusion-related fluid-rock interaction associated with heating of nearby sulfide-bearing schists of the Berwick Formation during Acadian orogenesis may have provided the necessary constituents for growth of sulfide phases in the Ayer. It appears that Late Devonian greenschist facies metamorphism and metasomatism led to mineralization that generated arsenopyrite and accompanying phosphates; however, the role of the cross-cutting Clinton Newbury Fault Zone as a conduit for hydrothermal fluids may also be important. Lower temperature As-bearing Fe-oxide and calcite coatings on open fractures surfaces may be associated with a change from lithostatic- to hydrostatic-pressures during post-glacial regional uplift. This mineralization appears to be synchronous with intense microfracturing that post-dates all other mineralization.},
	keywords = {$\#$StaffPubs, acadian, arsenic, arsenides, arsenopyrite, Ayer Granodiorite, Berwick formation, fractured materials, geochemistry, granodiorites, Igneous and metamorphic petrology 05A, igneous rocks, lower Paleozoic, massachusetts, Merrimack Synclinorium, metals, metamorphic rocks, metamorphism, metasedimentary rocks, metasomatism, Middlesex County Massachusetts, migration of elements, mineralization, Mineralogy of non-silicates 01C, northeastern Massachusetts, orogeny, Paleozoic, plutonic rocks, pollutants, pollution, pyrite, sulfides, United States},
	isbn = {00167592},
	url = {https://gsa.confex.com/gsa/2010NE/finalprogram/abstract_169998.htm},
	author = {Koteas, G. Christopher and Keskula, Anna J. and Stein, Carol L. and McTigue, David F. and Joseph P Kopera and Brandon, William C.}
}
