%0 Conference Proceedings %B Abstracts with Programs - Geological Society of America %D 2011 %T Identifying and examining potential geothermal resources in non-traditional regions, examples from the northeastern U.S. %A Koteas, G. Christopher %A John Michael Rhodes %A Stephen B Mabee %A Goodhue, Nathaniel %A Adams, Sharon A. %K #StaffPubs %K Andover Granite %K Eastern U.S. %K Economic geology, geology of energy sources 29A %K exploitation %K exploration %K Fall River Granite %K field studies %K geochemistry %K geothermal energy %K identification %K mapping %K massachusetts %K models %K Northeastern U.S. %K overburden %K resources %K sampling %K southeastern Massachusetts %K spectra %K structural analysis %K technology %K temperature %K United States %K whole rock %K X-ray fluorescence spectra %X The search for geothermal resources is rapidly expanding into tectonic regions that have not been previously considered to be suitable for exploitation. Many of these regions, such as the northeastern U.S., have never been the site of extensive geophysical investigations and have few deep borehole temperature measurements. Nevertheless, large portions of the northeastern U.S. are underlain by granitic bedrock that may be a productive energy source by applying enhanced geothermal technologies. In the absence of traditional reconnaissance data, we utilize field studies and sampling together with geochemical analysis to develop models of geothermal resources that can be tested against data from deep boreholes. Heat production is calculated from the measured density of the samples, the concentrations of K, U, and Th from whole-rock geochemical analysis via X-ray fluorescence, and established radiogenic heat production values. Models for a particular area can then be generated by calculating depth-specific temperatures using heat production, measured thermal conductivity for each sample, and assumptions related to local stratigraphy and regional heat flow. Mapping and structural extrapolation are used to establish the subsurface characteristics at a study site and are combined with the thermal and chemical characteristics of contact rocks and overburden materials. Two examples of the application of this technique are the Fall River granite at the margin of the Narragansett Basin in southeastern Massachusetts and the Andover Granite in northeastern Massachusetts. Thermal models of the Fall River Pluton indicate average temperatures of 71 degrees C at depths of 4 km and 97 degrees C at 6 km. Average temperatures increase to 107 degrees C and 132 degrees C, respectively, when a 2 km thick sediment package is modeled overlying the granite. The Andover Granite, which is not associated with a sedimentary basin and is in a more structurally complex configuration, yields an average temperature of 74 degrees C at a depth of 4 km and 101 degrees C at 6 km. While this approach to modeling temperature-depth profiles requires some regional heat flow assumptions, the application of mapping and structural analysis with geochemistry and thermal conductivity studies can be an important reconnaissance tool for identifying non-traditional geothermal resources. %B Abstracts with Programs - Geological Society of America %I Geological Society of America (GSA) : Boulder, CO, United States %C United States %V 43 %P 40 - 40 %8 2011/10/01/ %@ 00167592 %G eng %N 55 %! Abstracts with Programs - Geological Society of America %0 Conference Proceedings %B Abstracts with Programs - Geological Society of America %D 2012 %T Implications for non-traditional geothermal resources in southern New England; variability in heat potential based on thermal conductivity and geochemistry studies %A Koteas, G. Christopher %A John Michael Rhodes %A Stephen B Mabee %A Ryan, Amy %A Schmidt, Joe %A League, Corey %A Goodhue, Nathaniel %A Adams, Sharon A. %A Gagnon, Teresa K. %A Thomas, Margaret A. %K #StaffPubs %K chemical composition %K Connecticut %K Economic geology, geology of energy sources 29A %K energy sources %K geothermal energy %K geothermal exploration %K granites %K heat flow %K igneous rocks %K massachusetts %K models %K New England %K plutonic rocks %K thermal conductivity %K United States %X 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. %B Abstracts with Programs - Geological Society of America %I Geological Society of America (GSA) : Boulder, CO, United States %C United States %V 44 %P 76 - 77 %8 2012/02/01/ %@ 00167592 %G eng %U https://gsa.confex.com/gsa/2012NE/finalprogram/abstract_200837.htm %N 22 %! Abstracts with Programs - Geological Society of America %0 Conference Proceedings %B Abstracts with Programs - Geological Society of America %D 2006 %T Implications of diurnal river fluctuations on mass transport in a valley-fill aquifer %A Brandon J Fleming %A David F Boutt %A Stephen B Mabee %K #StaffPubs %K aquifers %K BEDROCK %K clastic sediments %K controls %K diffusion %K diurnal variations %K drainage %K drift %K Eastern U.S. %K Environmental geology 22 %K floods %K fluctuations %K geochemical cycle %K geologic hazards %K ground water %K measurement %K mixing %K models %K Northeastern U.S. %K numerical models %K nutrients %K pollution %K processes %K pumping %K quantitative analysis %K residence time %K sediments %K shallow aquifers %K surface water %K three-dimensional models %K tracers %K transport %K United States %K valleys %K water pollution %K water resources %K water wells %X Aquifers located in isolated stratified drift deposits in the northeastern portion of the US are extremely fragile and important groundwater resources. These aquifers, when restricted to bedrock valleys, are often strongly coupled to significant surface water drainage systems. In northwestern Massachusetts, surface water associated with the Deerfield River watershed is highly regulated by dams to protect against flooding and to generate hydroelectric power. Regular releases of water from these dams cause diurnal fluctuations in river stage. In a previous study performed by the USGS, measurements from two clusters of wells show a significant response to river stage fluctuations in the aquifer. Fluctuations in river stage and resulting changes in head levels in the aquifer cause a switch from a losing to a gaining stream. The flow reversals have implications for mass transport and nutrient cycling within the hyporheic zone. In this paper we investigate the physical hydrologic controls on mass transport in the shallow aquifer. Using a coupled groundwater flow and transport code, we built a quasi three dimensional transient numerical model to approximate the head changes in the aquifer caused by the stage fluctuations in the river. Flow velocities and residence times were estimated in the aquifer for a variety of flow conditions. The mixing process driven by the aquifer head changes were quantified in the proximity of the hyporheic zone and shown to significantly influence both vertical and horizontal flow velocities in a region close to the stream-aquifer boundary. The diurnal river stage changes also appear to influence farfield hydrologic conditions and potentially hydrologically isolate the river and hyporheic zone. To further investigate these mixing processes we applied a mass transport code with conservative tracers to the aquifer. Fluctuation of the river stage combined with the heterogeneous nature of the aquifer creates a pumping mechanism that creates excess mixing within shallow portions of the aquifer. Aquifer dispersivity and molecular diffusion both contribute to the anomalous mixing modeled in the shallow aquifer. Mixing driven by stream stage changes has important implications for nutrient cycling as well as contaminant transport in the shallow aquifer. %B Abstracts with Programs - Geological Society of America %I Geological Society of America (GSA) : Boulder, CO, United States %C United States %V 38 %P 468 - 468 %8 2006/10/01/ %@ 00167592 %G eng %U https://gsa.confex.com/gsa/2006AM/finalprogram/abstract_115285.htm %N 77 %! Abstracts with Programs - Geological Society of America %0 Conference Proceedings %B Geological Society of America Abstracts with Programs %D 2013 %T Improving seismic hazard assessment in New England through the use of surficial geologic maps and expert analysis %A Becker, Laurence R. %A Patriarco, Steven P. %A Marvinney, Robert G. %A Thomas, Margaret A. %A Stephen B Mabee %A Fratto, Edward S. %K #StaffPubs %K earthquakes %K Environmental geology %K geologic hazards %K maps %K natural hazards %K New England %K risk assessment %K seismic risk %K seismic zoning %K surficial geology %K surficial geology maps %K technology %K United States %X In New England, earthquakes pose a risk to the built environment. New England state geological surveys partnered with the Northeast States Emergency Consortium to integrate geologic information and GIS analysis for risk communication. Connecticut, Maine, Massachusetts, and Vermont employed surficial geologic maps, deglaciation history, glacial stratigraphy, and professional judgment to reclassify surficial geologic materials into one of the five National Earthquake Hazard Reduction Program (NEHRP) site classifications (A, B, C, D, and E). These new classifications were used in the HAZards U.S. Multi-Hazard (HAZUS-MH) risk assessment application as a substitute for site class value of "D," used in HAZUS-MH throughout New England as a default value. Coding of surficial geologic materials for the five NEHRP site classifications was then compared with classifications using the Wald methodology, a method using slope analysis as a proxy for shear-wave velocity estimates. Comparisons show that coding to site classes using the Wald methodology underestimates categories A (high-velocity shear-wave materials, least relative hazard) and E (lowest-velocity shear-wave materials, greatest relative hazard) when evaluated side by side with coding done with the aid of surficial geologic maps. Geologic maps provide insights into the location of buried low shear wave velocity materials not afforded by the Wald methodology. North of the glacial limit, derangement of drainage resulted in extensive ponding of meltwaters and the subsequent deposition of thick sequences of lacustrine mud. Inundation by the sea immediately following deglaciation in New England resulted in the deposition of spatially extensive and locally thick sequences of glacial marine mud. Surficial geologic maps better capture these circumstances when compared with the Wald methodology. Without the use of surficial geologic maps, significant areas of New England will be incorrectly classified as being more stable than actual site conditions would allow. By employing surficial geologic information, HAZUS-MH earthquake loss estimates are improved, providing local and regional emergency managers with more accurate information for locating and prioritizing.

%B Geological Society of America Abstracts with Programs %I Geological Society of America (GSA) : Boulder, CO, United States %C United States %V 45 %P 50 - 51 %8 2013/02/01/ %@ 00167592 %G eng %U https://gsa.confex.com/gsa/2013NE/webprogram/Paper214837.html %N 11 %! Abstracts with Programs - Geological Society of America %0 Conference Proceedings %B Geological Society of America Abstracts with Programs %D 2008 %T The influence of ductile structure and rheological heterogeneity on brittle structures as exhibited by Avalonian granites in southeastern Massachusetts %A Joseph P Kopera %K #StaffPubs %K acadian %K alleghenian %K avalon %K BEDROCK %K dikes %K foliation %K fracture %K fracture system %K fracture trace %K fractures %K granite %K granites %K Hopkinton %K joints %K l-tectonites %K lineaments %K lineation %K Milford %K Upton %X The orientation and geographic distribution of joints, veins, and brittle faults show a conspicuous correlation with the heterogeneous distribution of foliation and lineation intensity in Neo-Proterozoic granites and their deformed counterparts in southeastern Massachusetts. Field mapping and stereonet analysis of brittle and ductile structural data collected during 1:24,000-scale geologic mapping of the Milford quadrangle yielded the following general observations, which suggest that the ductile deformational history of this region appears to have strongly influenced the later development of brittle structures in the same rocks: The behavior of these fractures in relation to ductile structure have implications for rheological constraints on tectonic models of the post-Alleghenian core of the New England Appalachians, hydrogeologic models of regional fractured bedrock aquifers, and the interpretation of topographic lineaments. %B Geological Society of America Abstracts with Programs %7 2 %I Geological Society of America (GSA) : Boulder, CO, United States %C Buffalo, NY %V 40 %P 3 %8 03/2008 %G eng %U https://gsa.confex.com/gsa/2008NE/finalprogram/abstract_134899.htm %0 Journal Article %J Water Resources Research %D 2009 %T Implications of anthropogenic river stage fluctuations on mass transport in a valley fill aquifer %A David F Boutt %A Brandon J Fleming %K #Hydro %K #WaterResources %K aquifers %K boundary conditions %K Charlemont %K Deerfield River basin %K fluctuations %K fluvial features %K Franklin County Massachusetts %K ground water %K human activity %K Hydrogeology 21 %K hydrology %K massachusetts %K numerical models %K preferential flow %K rivers %K shallow aquifers %K streams %K surface water %K transport %K two-dimensional models %K United States %K valleys %X In humid regions a strong coupling between surface water features and groundwater systems may exist. In these environments the exchange of water and solute depends primarily on the hydraulic gradient between the reservoirs. We hypothesize that daily changes in river stage associated with anthropogenic water releases (such as those from a hydroelectric dam) cause anomalous mixing in the near-stream environment by creating large hydraulic head gradients between the stream and adjacent aquifer. We present field observations of hydraulic gradient reversals in a shallow aquifer. Important physical processes observed in the field are explicitly reproduced in a physically based two-dimensional numerical model of groundwater flow coupled to a simplistic surface water boundary condition. Mass transport simulations of a conservative solute introduced into the surface water are performed and examined relative to a stream condition without stage fluctuations. Simulations of 20 d for both fluctuating river stage and fixed high river stage show that more mass is introduced into the aquifer from the stream in the oscillating case even though the net water flux is zero. Enhanced transport by mechanical dispersion leads to mass being driven away from the hydraulic zone of influence of the river. The modification of local hydraulic gradients is likely to be important for understanding dissolved mass transport in near-stream aquifer environments and can influence exchange zone processes under conditions of high-frequency stream stage changes. %B Water Resources Research %I American Geophysical Union : Washington, DC, United States %V 45 %P @CitationW04427 - @CitationW04427 %8 2009/01/01/ %@ 0043139719447973 %G eng %U http://onlinelibrary.wiley.com/doi/10.1029/2007WR006526/full %N 44 %! Water Resources Research %0 Journal Article %J Special Paper - Geological Society of America %D 2012 %T Improving seismic hazard assessment in New England through the use of surficial geologic maps and expert analysis %A Becker, Laurence R. %A Patriarco, Steven P. %A Marvinney, Robert G. %A Thomas, Margaret A. %A Stephen B Mabee %A Fratto, Edward S. %K #StaffPubs %K civil engineering %K earthquakes %K Eastern U.S. %K Engineering geology 30 %K Environmental geology 22 %K geologic hazards %K mitigation %K natural hazards %K New England %K Northeastern U.S. %K risk assessment %K risk management %K safety %K seismic risk %K seismicity %K United States %X (GSA Special Paper) In New England, earthquakes pose a risk to the built environment. Emergency preparedness and mitigation planning are prudent in this region as older unreinforced masonry buildings and numerous critical facilities are common. New England state geological surveys cooperate with the Northeast States Emergency Consortium (NESEC) to improve risk communication with emergency managers. To that end, Connecticut, Maine, Massachusetts, and Vermont employed surficial geologic maps, deglaciation history, knowledge of the glacial stratigraphy, and professional judgment to reclassify surficial geologic material units into one of the five National Earthquake Hazards Reduction Program (NEHRP) site classifications (A, B, C, D, and E). These new classifications were used as a substitute for the HAZards U.S. Multi-Hazard (HAZUS-MH) site class value of "D," which is used throughout New England as a default value. In addition, coding of surficial geologic materials for the five NEHRP site classifications was compared with classifications using the Wald methodology, a method that uses a slope analysis as a proxy for shear-wave velocity estimates. Comparisons show that coding to site classes using the Wald methodology underestimates categories A (high-velocity shear-wave materials, least relative hazard) and E (lowest-velocity shear-wave materials, greatest relative hazard) when evaluated side by side with coding done with the aid of surficial geologic maps. North of the glacial limit, derangement of drainage resulted in extensive ponding of meltwaters and the subsequent deposition of thick sequences of lacustrine mud. Inundation by the sea immediately following deglaciation in New England resulted in the deposition of spatially extensive and locally thick sequences of glacial marine mud. Surficial geologic maps better capture this circumstance when compared with the Wald topographic slope analysis. Without the use of surficial geologic maps, significant areas of New England will be incorrectly classified as being more stable than the site conditions that actually exist. By employing surficial geologic information, we project an improved accuracy for HAZUS-MH earthquake loss estimations, providing local and regional emergency managers with more accurate information for locating and prioritizing earthquake planning, preparedness, and mitigation projects to reduce future losses. %B Special Paper - Geological Society of America %I Geological Society of America (GSA) : Boulder, CO, United States %C United States %V 493 %P 221 - 242 %8 2012/01/01/ %@ 007210779780813724935 %G eng %U http://specialpapers.gsapubs.org/content/493/221.abstract %! Special Paper - Geological Society of America %0 Journal Article %J Journal of Structural Geology %D 2008 %T Influence of rock fabric on fracture attribute distribution and implications for groundwater flow in the Nashoba Terrane, eastern Massachusetts %A Alex K Manda %A Stephen B Mabee %A Donald U Wise %K #StaffPubs %K foliation %K fractures %K ground water %K Hydrogeology 21 %K joints %K massachusetts %K movement %K Nashoba terrane %K preferred orientation %K statistical distribution %K structural analysis %K Structural geology %K style %K terranes %K United States %X Attributes (i.e. trace-length, spacing, termination and orientation) of joints and foliation-parallel fractures (FPFs) are used to assess the influence of lithology and fabric on fracture type and distribution in metamorphic and igneous rocks of the Nashoba terrane, Massachusetts. Orientations of NE-SW and NW-SE trending joints are consistent throughout the region, whereas FPFs are sub-parallel to the axis of the terrane. Joint spacing generally decreases to the northeast across the terrane reflecting lithologic changes from metamorphic to igneous rock types. Although trace-length and spacing frequency distributions of both joints and FPFs are best described by lognormal functions, FPFs possess narrower fracture spacing than joints. Median fracture trace-lengths of all FPFs are comparable to those of all steep joints, but the median fracture spacing is half that of all steep joints. Trace-lengths of FPFs vary as a function of the degree of development of foliation. Fracture attributes and groundwater flow models suggest that FPFs may significantly increase fracture connectivity and potential for groundwater recharge. FPFs may account for as much as 30% of flow in fracture networks suggesting that in addition to joints, FPFs play a significant role in groundwater hydraulics that may include imparting flow anisotropy on the groundwater system. %B Journal of Structural Geology %I Elsevier : Oxford, International %C International %V 30 %P 464 - 477 %8 2008/04/01/ %@ 01918141 %G eng %U http://www.sciencedirect.com/science/article/pii/S0191814107002362 %N 44 %! Journal of Structural Geology %0 Report %D 2001 %T An Information Survival Kit for the prospective geothermal heat pump owner %K #Geothermal %K #GeothermalHomeownerResources %K alternative energy %K geothermal %K green energy %K ground source heat pumps %K GSHP %K heat pump %K renewable energy %K renewables %K standing column %X Geothermal heat pumps (GHPs), although not a new technology, remain a small (but growing) player in the residential heating/cooling sector. Although somewhat higher in first cost, this technology can, in the right application, quickly repay this cost premium through savings in energy costs. Despite all the positive publicity on GHPs, they are not for everyone. Like any other heating and cooling system, GHPs tend to fit well in certain circumstances and poorly in others. Familiarizing yourself with the factors that effect the feasibility of GHPs will assist you in making an informed decision as to their suitability for your home. It is the intention of this package to provide that information and to address some of the commonly asked questions regarding the technology. Please feel free to contact us if you have questions not covered in this package. %I Geo-Heat Center, Oregon Institute of Technology %C Klamath Falls, OR %G eng %U http://geoheat.oit.edu/ghp/survival.pdf