@proceedings {281, title = {Deep geothermal resource potential in Connecticut; progress report}, volume = {44}, year = {2012}, note = {Accession Number: 2012-090080; Conference Name: Geological Society of America, Northeastern Section, 47th annual meeting; Hartford, CT, United States; Conference Date: 20120318; Language: English; Coordinates: N405900N420300W0714800W0734400; Coden: GAAPBC; Collation: 1; Collation: 77; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 201247; Monograph Title: Geological Society of America, Northeastern Section, 47th annual meeting; Monograph Author(s): Anonymous; Reviewed Item: Analytic}, month = {2012/02/01/}, pages = {77 - 77}, publisher = {Geological Society of America (GSA) : Boulder, CO, United States}, address = {United States}, abstract = {The Connecticut and Massachusetts Geological Surveys are collaborating on a National Geothermal Data Project funded by the US Department of Energy through the Association of American State Geologists.Geothermal resources in Connecticut (CT) to date have been exploited using near surface ground source heat pump technology. This is the first investigation of CT deep geothermal resources. Many CT granitoids contain heat producing elements. The goal is to identify geologic units capable of producing enough heat, at reasonable drilling depths, to operate a viable geothermal power plant. Target rock units must contain enough uranium, thorium and potassium (U/Th/K) in combination with heat generated through the natural geothermal gradient of the Earth to generate electricity and co-produced direct heating. Heat at depth can be concentrated by an overlying insulating layer of sedimentary rocks and glacial sediments. 27 CT bedrock units were selected for sampling using existing mapping. 120 samples were analyzed using X-Ray Fluorescence Spectrometry. Heat production values (HPVs) at or greater than 4 mu W/m (super 3) were considered to be of interest. Values ranging from 4 to 18 mu W/m (super 3) were calculated for 7 of the 27 rock units. Elevated concentrations of thorium, ranging from 10.5 ppm to 245 ppm, were the primary contributors to increased HPVs. Initial results indicate that the warmest rocks are Permian and Precambrian, which is consistent with earlier results from granitoid bodies underlying the Atlantic Coastal Plain of Virginia (Speer et al., 1979). Additional bedrock samples will be analyzed to further characterize geochemical variations and potential HPVs of target rock units. Direct thermal conductivity measurements are being made of select bedrock samples in addition to sedimentary rocks of the Hartford Basin. Theoretical thermal profiles derived from rock geochemistry will provide an estimate of heat generated at depth for geologic units of interest and assist in determining the potential for an insulating layer overlying heat producing granitoids. Direct thermal conductivity measurements of unconsolidated materials throughout CT are also being made to support the ground-source heat pump industry. All data and mapping will be accessible via the National Geothermal Data System (NGDS).}, keywords = {$\#$StaffPubs, Connecticut, Economic geology, geology of energy sources 29A, energy sources, geothermal energy, geothermal exploration, geothermal gradient, granites, heat flow, igneous rocks, New England, plutonic rocks, temperature, thermal conductivity, United States}, isbn = {00167592}, url = {https://gsa.confex.com/gsa/2012NE/finalprogram/abstract_200494.htm}, author = {Gagnon, Teresa K. and Koteas, G. Christopher and Thomas, Margaret A. and Stephen B Mabee and John Michael Rhodes} } @proceedings {298, title = {Granite as a geothermal resource in the Northeast}, volume = {44}, year = {2012}, note = {Accession Number: 2012-090078; Conference Name: Geological Society of America, Northeastern Section, 47th annual meeting; Hartford, CT, United States; Conference Date: 20120318; Language: English; Coden: GAAPBC; Collation: 1; Collation: 76; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 201247; Monograph Title: Geological Society of America, Northeastern Section, 47th annual meeting; Monograph Author(s): Anonymous; Reviewed Item: Analytic}, month = {2012/02/01/}, pages = {76 - 76}, publisher = {Geological Society of America (GSA) : Boulder, CO, United States}, address = {United States}, abstract = {In the absence of volcano-derived hydrothermal activity and high heat flow, granitic plutons provide an alternative geothermal resource from which heat may be usefully extracted. Compared with other crustal rocks, granites contain higher concentrations of the heat producing elements (K, U, Th). Additionally, they are more homogeneous and have simpler fracture systems than surrounding country rock, allowing for stimulation through hydro-fracking of large (>1 km (super 3) ) geothermal reservoirs. However, not all granites are created equal! Those with heat production > 5 mu W/m (super 3) , or with deep batholithic roots, are the most promising. Estimated temperatures at a given depth are related to the heat production, thickness and thermal conductivity of the granite. For example, the Carnmenellis Pluton in Cornwall, England (which will be drilled in 2012) is estimated to have temperatures in excess of 170 degrees C at a depth of 5 km, which is sufficient for co-production of electricity and hot water for heating. More importantly, granite bodies that are buried beneath thick sequences of thermally insulating sediments are also potential geothermal targets. Most successful examples to date include the Soultz sur Foret project in France, with temperatures of 200 degrees C at a depth of 5 km. (and which is currently producing electricity), Innamincka, Australia, with temperatures of 250 degrees C at a depth of 4 km. (which will be producing in 2012), and the seismically ill-fated project in Basel, Switzerland. Surely, if such projects involving the geothermal potential of granites, can succeed elsewhere, they can succeed here in the granite-rich Northeast? The geothermal potential of the Conway Granite, NH has long been recognized. Other possibilities include the Fitchburg Pluton, MA, and granites buried beneath the Carboniferous sediments of the Narragansett Basin and the Triassic sediments of the Connecticut River valley.}, keywords = {$\#$StaffPubs, Cammenallis Pluton, Cornwall England, Eastern U.S., Economic geology, geology of energy sources 29A, energy sources, England, Europe, geothermal energy, geothermal exploration, granites, Great Britain, heat flow, hydrothermal conditions, igneous rocks, intrusions, Northeastern U.S., plutonic rocks, plutons, thermal conductivity, United Kingdom, United States, Western Europe}, isbn = {00167592}, url = {https://gsa.confex.com/gsa/2012NE/finalprogram/abstract_200603.htm}, author = {John Michael Rhodes and Koteas, G. Christopher and Stephen B Mabee} } @proceedings {301, title = {Implications for non-traditional geothermal resources in southern New England; variability in heat potential based on thermal conductivity and geochemistry studies}, volume = {44}, year = {2012}, note = {Accession Number: 2012-090079; Conference Name: Geological Society of America, Northeastern Section, 47th annual meeting; Hartford, CT, United States; Conference Date: 20120318; Language: English; Coordinates: N420000N473000W0670000W0733000; Coden: GAAPBC; Collation: 2; Collation: 76-77; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 201247; Monograph Title: Geological Society of America, Northeastern Section, 47th annual meeting; Monograph Author(s): Anonymous; Reviewed Item: Analytic}, month = {2012/02/01/}, pages = {76 - 77}, publisher = {Geological Society of America (GSA) : Boulder, CO, United States}, address = {United States}, abstract = {Estimating geothermal potential in southern New England in the absence of borehole heat flow data or geophysical studies has led to a focus on models based on thermal conductivity, geochemistry, and density-based heat production models. Preliminary estimates of geothermal potential generally match borehole-based heat flow data from similar tectonic environments. Nevertheless, microstructural and compositional heterogeneity with depth remain largely unconstrained. The extrapolation of regional structures based on detailed field mapping has helped to improve structural projections adjacent to major basins. However, an additional source of error in models of heat potential-with-depth are thermal conductivity estimates of igneous and meta-igneous rocks throughout Massachusetts (MA) and Connecticut (CT). Over three hundred granitoid localities in MA and CT have been analyzed to date. The southern New England region can be simplified into four major litho-tectonic zones: the Taconic-Berkshire Zone of western MA and northwestern CT, The Bronson Hill Zone associated with the CT River valley, the Nashoba Zone of central MA and eastern CT, and the Milford-Dedham Zone of eastern MA and eastern CT. Granitic rocks adjacent to the CT River valley and the Narragansett Basin vary considerably in thermal conductivity. Granites adjacent to the Narragansett Basin vary from 2.9 to 3.7 W/m * K. Average thermal conductivity values, combined with modeled heat production values, produce temperatures at 3 km depth along the Narragansett Basin that approach 85-115 degrees C. Values of meta-igneous rocks from the margin of the CT River valley in MA and CT vary more considerably in thermal conductivity, from 1.8 to 3.9W/m * K. Modeled heat potentials at 3 km depths along the eastern margin of the CT River valley vary between 74-122 degrees C and appear to be largely related to compositional variation. However, local rock composition is also related to metamorphic grade and fabric development, suggesting that both fabric and composition are first order controls on thermal conductivity. Modeling based on these data set to date suggests that combining thermal conductivity, whole rock geochemistry data, and density measurements can produce accurate reconnaissance estimates of geothermal potential in southern New England.}, keywords = {$\#$StaffPubs, chemical composition, Connecticut, Economic geology, geology of energy sources 29A, energy sources, geothermal energy, geothermal exploration, granites, heat flow, igneous rocks, massachusetts, models, New England, plutonic rocks, thermal conductivity, United States}, isbn = {00167592}, url = {https://gsa.confex.com/gsa/2012NE/finalprogram/abstract_200837.htm}, author = {Koteas, G. Christopher and John Michael Rhodes and Stephen B Mabee and Ryan, Amy and Schmidt, Joe and League, Corey and Goodhue, Nathaniel and Adams, Sharon A. and Gagnon, Teresa K. and Thomas, Margaret A.} } @article {335, title = {The Massachusetts Geothermal Data Project}, year = {2013}, publisher = {Massachusetts Geological Survey}, abstract = {A series of geothermal maps and datasets for Massachusetts derived from data collected by the MGS for Massachusetts and Connecticut. These data include whole rock geochemistry, rock and soil thermal conductivity, hot spring aqueous geochemistry, and derivative thermal and heatflow modeling. The project includes multiple datasets and products which can be accessed here or via the National Geothermal Data System (http://search.geothermaldata.org/dataset?q=Massachusetts). These datasets and products are: Maps: Comprising MGS Miscellaneous Maps 13-01 through 13-08 Data: can be downloaded from the links below