@proceedings {272,
	title = {Characterizing fractured crystalline bedrock aquifers using hydrostructural domains in the Nashoba Terrane, eastern Massachusetts},
	volume = {38},
	year = {2006},
	note = {Accession Number: 2007-032741; Conference Name: Geological Society of America, 2006 annual meeting; Philadelphia, PA, United States; Conference Date: 20061022; Language: English; Coden: GAAPBC; Collation: 1; Collation: 25; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 200709; Monograph Title: Geological Society of America, 2006 annual meeting; Monograph Author(s): Anonymous; Reviewed Item: Analytic},
	month = {2006/10/01/},
	pages = {25 - 25},
	publisher = {Geological Society of America (GSA) : Boulder, CO, United States},
	address = {United States},
	abstract = {Fractured crystalline bedrock aquifers are good sources of potable water in many parts of the world. However, siting of highly productive wells in these rock units remains a challenging and expensive task because fracture development at the regional scale is both heterogeneous and anisotropic. Using low cost field data to define units of rock that have similar lithologic and fracture characteristics can significantly reduce time and energy spent on determining areas with better than average aquifer productivity. These physical characteristics that impart a particular hydraulic character on rocks are used to delineate regions with similar hydrologic characteristics called hydrostructural domains (Mackie, 2002). Hydrostructural domains are delineated from fracture characterization data that were collected from 79 outcrops located in the Nashoba Terrane of eastern Massachusetts. Information collected and used to delineate the domains include the number and distribution of fracture sets, types of fractures present or absent, the degree of fracture development, fracture intensity/density, fracture connectivity and rock type. Discrete fracture networks are generated from the fracture characterization data to simulate groundwater flow in the region. Conductivity of particular units is evaluated and compared to results from existing pumping tests obtained from the US Geological Survey. Preliminary results indicate that there is great value in utilizing fracture characteristic data obtained from surface outcrops to predict subsurface groundwater flow characteristics of fractured bedrock aquifers. Water managers, developers and decision makers are eager to know which areas are the most promising for encountering highly conductive zones in the subsurface. Collecting extensive structural data from surface outcrops, although not as accurate as drilling wells, is a cheaper alternative that could provide at least a rough estimate of the hydraulic properties of fractured rocks leading to effective siting of new water wells. Hydrostructural domain maps may pinpoint specific areas that have a high potential for wells to encounter highly conductive zones and could therefore be a powerful tool in transferring information from one site to another without having to repeatedly undertake extensive site characterization.},
	keywords = {$\#$StaffPubs, anisotropy, aquifers, BEDROCK, characterization, connectivity, crystalline rocks, eastern Massachusetts, fractures, ground water, heterogeneity, hydraulic conductivity, Hydrogeology 21, massachusetts, Nashoba terrane, outcrops, physical properties, site exploration, United States, water wells},
	isbn = {00167592},
	url = {https://gsa.confex.com/gsa/2006AM/finalprogram/abstract_113075.htm},
	author = {Alex K Manda and Stephen B Mabee and David F Boutt}
}
@proceedings {289,
	title = {Factors influencing groundwater inflows in a newly constructed cross-strike tunnel, eastern Massachusetts; 5, Geochemical interpretation of groundwater inflows},
	volume = {31},
	year = {1999},
	note = {Accession Number: 2001-037342; Conference Name: Geological Society of America, 1999 annual meeting; Denver, CO, United States; Conference Date: 19991025; Language: English; Coden: GAAPBC; Collation: 1; Collation: 348; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 200111; Monograph Title: Geological Society of America, 1999 annual meeting; Monograph Author(s): Anonymous; Reviewed Item: Analytic},
	month = {1999/01/01/},
	pages = {348 - 348},
	publisher = {Geological Society of America (GSA) : Boulder, CO, United States},
	address = {United States},
	abstract = {Samples of ground and surface waters in and above the tunnel (Curry et al., this volume) were collected to characterize the chemistry of groundwater discharging from fractures and faults. Forty-two water samples were collected: 32 along a transect of the tunnel and 10 from surface waters above the trace of the tunnel. All samples were analyzed for major anions and cations, and delta (super 18) O. Analysis of the anion/cation data indicated that these waters are dominated by sulfate+chloride and calcium+magnesium. However, five sub-classifications can be discerned based on the relative concentrations of ions in the samples. The five sub-classifications are Cl > HCO (sub 3) > SO (sub 4) > NO (sub 3) :Ca > Na+K > Mg (15 samples), Cl > HCO (sub 3) > SO (sub 4) > NO (sub 3) :Na+K > Ca > Mg (7 samples), Cl > HCO (sub 3) > SO (sub 4) > NO (sub 3) :Ca > Mg > Na+K (6 samples), Cl > SO (sub 4) > HCO (sub 3) > NO (sub 3) :Na+K > Ca > Mg (3 samples), and HCO (sub 3) > Cl > SO (sub 4) > NO (sub 3) :Ca > Na+K > Mg (2 samples). Results from statistical analyses indicate that alkalinity, calcium, sodium and potassium do vary as a function of bedrock type and that these differences are significant at the 95\% confidence level.In addition, preliminary oxygen isotope data indicate that two large, discrete water producing fault zones located in the eastern part of the tunnel are isotopically enriched (average delta (super 18) O = -7.75) relative to other water producing features in the tunnel (average delta (super 18) O = -8.96). The delta (super 18) O values obtained from all surface water bodies located above the tunnel average -7.56 whereas those values in surface ponds immediately above the fault zones average -6.71. Nitrate levels also show elevated levels in two water producing fault zones (>10 mg/L for some samples) and may result from accidental contamination during sampling, the use of explosives at discrete locations in the tunnel, or from leaking septic systems. The results of the oxygen isotope and nitrate analyses also suggest that some of the fault zones in the tunnel may have a rapid and direct hydraulic connection to the surface.},
	keywords = {$\#$StaffPubs, anions, BEDROCK, cations, classification, discharge, eastern Massachusetts, fault zones, faults, geochemistry, ground water, hydraulic conductivity, hydrochemistry, Hydrogeology 21, Isotope geochemistry 02D, isotope ratios, isotopes, massachusetts, movement, New England, nitrate ion, O-18/O-16, oxygen, samples, stable isotopes, surface water, tunnels, United States},
	isbn = {00167592},
	author = {Weaver, Rebecca A. and Stephen B Mabee and Williams, Katherine W. and Curry, Patrick J.}
}
@proceedings {308,
	title = {Lineaments; their value in assessing regional groundwater availability and quality in bedrock aquifers of glaciated metamorphic terrains; a case study},
	volume = {25},
	year = {1993},
	note = {Accession Number: 1993-017600; Conference Name: Geological Society of America, Northeastern Section, 28th annual meeting; Burlington, VT, United States; Conference Date: 19930322; Language: English; Coden: GAAPBC; Collation: 1; Collation: 35; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 1993; Monograph Title: Geological Society of America, Northeastern Section, 28th annual meeting; Monograph Author(s): Anonymous; Reviewed Item: Analytic},
	month = {1993/03/01/},
	pages = {35 - 35},
	publisher = {Geological Society of America (GSA) : Boulder, CO, United States},
	address = {United States},
	keywords = {$\#$StaffPubs, amphibolite, aquifers, Atlantic Coastal Plain, BEDROCK, central Maine, fractures, Georgetown Maine, ground water, hydraulic conductivity, hydrogeology, lineaments, Maine, metamorphic rocks, structural controls, United States, water quality},
	isbn = {00167592},
	issn = {0016-7592},
	author = {Stephen B Mabee}
}
@article {264,
	title = {A field study (Massachusetts, USA) of the factors controlling the depth of groundwater flow systems in crystalline fractured-rock terrain},
	journal = {Hydrogeology Journal},
	volume = {18},
	year = {2010},
	note = {Accession Number: 2011-042136; Language: English; Coordinates: N420000N425000W0695500W0714500; Collation: 16; Publication Types: Serial; Updated Code: 201124; Illustration(s): illus. incl. 3 tables, geol. sketch map; Number of References: 58; Reviewed Item: Analytic},
	month = {2010/12/01/},
	pages = {1839 - 1854},
	publisher = {Springer : Berlin - Heidelberg, Germany},
	address = {Federal Republic of Germany},
	abstract = {Groundwater movement and availability in crystalline and metamorphosed rocks is dominated by the secondary porosity generated through fracturing. The distributions of fractures and fracture zones determine permeable pathways and the productivity of these rocks. Controls on how these distributions vary with depth in the shallow subsurface (<300 m) and their resulting influence on groundwater flow is not well understood. The results of a subsurface study in the Nashoba and Avalon terranes of eastern Massachusetts (USA), which is a region experiencing expanded use of the fractured bedrock as a potable-supply aquifer, are presented. The study logged the distribution of fractures in 17 boreholes, identified flowing fractures, and hydraulically characterized the rock mass intersecting the boreholes. Of all fractures encountered, 2.5\% are hydraulically active. Boreholes show decreasing fracture frequency up to 300 m depth, with hydraulically active fractures showing a similar trend; this restricts topographically driven flow. Borehole temperature profiles corroborate this, with minimal hydrologically altered flow observed in the profiles below 100 m. Results from this study suggest that active flow systems in these geologic settings are shallow and that fracture permeability outside of the influence of large-scale structures will follow a decreasing trend with depth. Copyright 2010 Springer-Verlag},
	keywords = {$\#$StaffPubs, aquifers, boreholes, crystalline rocks, eastern Massachusetts, fractured materials, fractures, ground water, hydraulic conductivity, Hydrogeology 21, massachusetts, Nashoba terrane, permeability, porosity, preferential flow, shallow-water environment, substrates, United States},
	isbn = {1431217414350157},
	url = {http://link.springer.com/article/10.1007\%2Fs10040-010-0640-y},
	author = {David F Boutt and Diggins, Patrick and Stephen B Mabee}
}
