@proceedings {275, title = {Connecticut geothermal map series; tools for exploration and development}, volume = {45}, year = {2013}, note = {Accession Number: 2014-021035; Conference Name: Geological Society of America, Northeastern Section, 48th annual meeting; Bretton Woods, NH, United States; Conference Date: 20130318; Language: English; Coden: GAAPBC; Collation: 1; Collation: 50; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 201414; Monograph Title: Geological Society of America, Northeastern Section, 48th annual meeting; Monograph Author(s): Anonymous; Reviewed Item: Analytic}, month = {2013/02/01/}, pages = {50 - 50}, publisher = {Geological Society of America (GSA) : Boulder, CO, United States}, address = {United States}, abstract = {The CT and MA Geological Surveys are collaborative partners in the National Geothermal Data Project funded by DOE through the Association of American State Geologists. The goal is to develop information to assist in locating State geothermal resources and provide data for better design of EGS systems in bedrock or unconsolidated sediments. The first 2 yrs of the investigation focused on data collection to explore the heat generating potential of CT bedrock and thermal conductivity (TC) properties of CT sediments. Rock chemistry, density, and TC were used to calculate heat production, heat flow, and thermal profiles at depth for >240 samples of 55 bedrock units. Heat production values (hpvs) were determined using concentrations of radiogenic (K, U, Th) and measured sample density. Heat flow values were determined using the calculated hpvs for the samples and hpvs of avg crustal material of New England (Rhodes, personal com., 2012). Thermal profiles at depths up to 6 km were generated using hpv, heat flow, and TC values for each sample. Results indicate that areas with highest heat flow values are in southeastern CT bedrock. 100 sediment samples were collected from 20 units targeted using the Surficial Materials and Quaternary Maps of CT. TC Measurements were made using a Decagon KD2-Pro Meter. Physical profiles of sediment (grain size, sand, silt, clay percent, bulk density, porosity) were created. Current efforts involve synthesis of calculated hpvs with direct heat flow measurements from existing geothermal installations to compile a geothermal resource map series. The series includes heat production, inferred heat flow, TC, and thermal profile maps for bedrock, and a TC map for sediments. These maps will assist geothermal contractors in site plan and system design. Heat production and inferred heat flow maps summarize model results for bedrock units. Thermal profile maps depict models of inferred temperature increases at depth, providing estimates for 3,4,5, and 6 km at specific locations, and provide depths needed to achieve desired temperature for either EGS or larger direct heat applications. TC mapping of sediments depict favorable areas for geothermal installations, and may be used in design of various ground source heat pump systems. All data and mapping is accessible via the National Geothermal Data System.}, keywords = {$\#$StaffPubs, BEDROCK, Connecticut, Economic geology, geology of energy sources 29A, geothermal energy, heat flow, information management, maps, technology, United States}, isbn = {00167592}, url = {https://gsa.confex.com/gsa/2013NE/webprogram/Paper216450.html}, author = {Gagnon, Teresa K. and Thomas, Margaret A. and John Michael Rhodes and Stephen B Mabee} } @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 {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.} }