%0 Conference Proceedings %B Abstracts with Programs - Geological Society of America %D 2004 %T Fracture characterization of crystalline bedrock for groundwater investigations; an example from the Marlborough Quadrangle, Massachusetts %A Scott A Salamoff %A Stephen B Mabee %A Joseph P Kopera %A Donald U Wise %K #StaffPubs %K aquifers %K Assabet River Fault %K BEDROCK %K characterization %K controls %K crystalline rocks %K fractured materials %K fractures %K geographic information systems %K ground water %K Hydrogeology 21 %K hydrology %K information systems %K joints %K Marlborough Quadrangle %K massachusetts %K Middlesex County Massachusetts %K permeability %K preferential flow %K recharge %K style %K testing %K theoretical models %K United States %X Integration of a wide array of structural data with well-field hydrologic testing is increasingly recognized as a critical step in understanding groundwater flow behavior and recharge in crystalline bedrock aquifers (Lyford et al., 2003, Walsh and Lyford, 2002). The Marlborough Quadrangle, about 40 km west of Boston, was selected as a test case of how a state geological survey can most effectively and efficiently collect and present such data in order to better constrain conceptual models of groundwater flow in general and to be of maximum use for hydrologists and consultants working on specific local problems. In this study, 3200 structural measurements were taken by a two-person team over a nine-week period at 68 stations distributed throughout the quadrangle and keyed into a GIS database. Specialized data sheets allowed efficient recording and digitization of orientations, lengths, spacing and mineralization, and separation of various classes of joints and veins. Fault data also included motion direction and sense. Summary maps in GIS format include standard geologic map bases overlain by typical rose diagrams and stereograms and maps such as fracture domains and trajectories, sheeting distribution, foliation trajectories, bedrock elevations, generalized piezometric surface configuration, and overburden type and thickness with separations into permeability class. Geology of the quadrangle can be separated into three zones: (a) north of the Assabet River Fault (ARF), (b) the area between the ARF and 1.5 km-wide Bloody Bluff Fault Zone (BBFZ), and (c) south of the BBFZ. Generalized foliations in the zones are: (a) 215, 50N, (b) 240, 65N, and (c) 270, 45N. Two pervasive, steeply-dipping (>60 degrees ) fracture sets occur throughout the quadrangle: an older 150 degrees set that includes sulfide-bearing veins and fracture surfaces along the ARF and a 015 degrees set of largely unmineralized common joints, macrojoints (>3 m length) and joint zones (av. 1.2 m width). Sheeting and unloading joints are generally coincident with shallow dipping foliation in (c) but cross-cut foliation in (a) and (b). We believe this approach will provide hydrologists and consultants with basic framework data that will expedite and improve the planning of subsurface investigations, construction activities and groundwater exploration. %B Abstracts with Programs - Geological Society of America %I Geological Society of America (GSA) : Boulder, CO, United States %C United States %V 36 %P 113 - 113 %8 2004/03/01/ %@ 00167592 %G eng %U https://gsa.confex.com/gsa/2004NE/finalprogram/abstract_70321.htm %N 22 %! Abstracts with Programs - Geological Society of America %0 Conference Proceedings %B Abstracts with Programs - Geological Society of America %D 2004 %T An update of geologic mapping in Massachusetts %A Joseph P Kopera %A Stephen B Mabee %A Scott A Salamoff %A Hildreth, Carol %K #StaffPubs %K data %K data acquisition %K data processing %K digital data %K Geologic maps 14 %K mapping %K massachusetts %K National Cooperative Geologic Mapping Program %K programs %K publications %K regional %K review %K STATEMAP %K United States %X Despite the state's relatively high population density and decades of detailed study of the bedrock geology, only about half of the 7.5' quadrangles in Massachusetts have been published as GQ series geologic maps. As the state's population continues to grow, the availability of basic geologic data becomes increasingly crucial for informed land-use and water-management decision making. Much of the published 1:24000 scale geologic mapping predates recent advances in the understanding of regional tectonics, and needs to be updated. The Office of the State Geologist has begun a geologic mapping program in Massachusetts to address these needs. Two mapping projects were conducted through the STATEMAP component of the National Cooperative Geologic Mapping program in 2003. These projects focused on 7.5' quadrangles along the I-495 corridor, which is experiencing extensive population growth and development. The first project involved conversion of published 1:24,000-scale surficial geology to digital form for 10 quadrangles in southeastern Massachusetts. A semi-automated process was developed for this project that easily converts published paper geologic maps into vectorized, georeferenced datalayers. The second project involved 1:24000-scale geologic mapping of the Marlborough quadrangle in east-central Massachusetts. Products include traditional maps of bedrock and surficial geology as well as two new prototype products: a fracture characterization map and a surficial materials map. These projects mark the first time in Massachusetts' history that quadrangle-scale geologic data will be available in digital form to consultants and stakeholders, thus greatly expediting and improving the use and analysis of all geologic data. In addition, the inclusion of fracture characterization and surficial materials maps adds substantially to the value of traditional geologic map products. The new maps provide supplemental data on the hydrologic characteristics of the bedrock and the vertical stacking of surficial deposits that previously was unavailable. STATEMAP projects in 2004 will continue to focus along the I-495 corridor, and will involve revision and new mapping in the Wilmington, Reading, South Groveland, Lawrence, Hudson, and Oxford quadrangles. %B Abstracts with Programs - Geological Society of America %I Geological Society of America (GSA) : Boulder, CO, United States %C United States %V 36 %P 58 - 58 %8 2004/03/01/ %@ 00167592 %G eng %N 22 %! Abstracts with Programs - Geological Society of America %0 Map %D 2006 %T Fracture characterization map of the Marlborough quadrangle, Massachusetts %A Stephen B Mabee %A Scott A Salamoff %K #FractureMaps %K #MGSPub %K Ashland %K Berlin %K fault %K fracture %K fracture trace %K groundwater %K Hopkinton %K Hudson %K hydrostructural domains %K joint %K lineament %K Malborough %K Northborough %K Southborough %K water resources %K Westborough %B Geologic Map %7 GM-06-02 v 2.1 %I Massachusetts Geological Survey %G eng %2

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