@book {344, title = {The bedrock geology of Massachusetts}, series = {U.S. Geological Survey Professional Paper}, volume = {1366}, number = {1366}, year = {1988}, publisher = {United States Geological Survey}, organization = {United States Geological Survey}, address = {Reston, VA}, abstract = {USGS Professional Paper 1366 A-D \& E-J: Books accompanying the 1983 State Bedrock Geologic Map, edited by Norman L. Hatch. Paper copies can be ordered via the USGS store (http://store.usgs.gov) using the USGS product numbers above or by clicking the links below.}, keywords = {$\#$MassGeology, $\#$MassGeologyMap, $\#$StateGeologicMap, bedrock map, GEOLOGIC MAP, Goldsmith, Hatch, Hatch 1991, State Geologic Map, Zen, Zen 1983}, issn = {978-0-607-71434-0 and 978-0-607-71433-3}, author = {Hatch, Norman L and Goldsmith, Richard and Robinson, P and Stanley, Rolfe S and Wones, David R and Zartman, Robert E and Marvin, Richard F} } @conference {369, title = {Latest Paleozoic through Mesozoic faults in north-central Massachusetts and their correlations with New Hampshire}, booktitle = {Geological Society of America - Northeastern section}, year = {2016}, publisher = {Geological Society of America}, organization = {Geological Society of America}, address = {Albany, NY}, abstract = {

Several faults in south-central New Hampshire can be extended into Massachusetts (MA) as a result of detailed mapping in both states since publication of the MA state bedrock geologic map in 1983. Many of these faults delineate and/or cut Devonian metamorphic isograds in the Silurian Merrimack Belt in northern MA, and juxtapose chlorite-grade rocks in the Nashua sub-belt (NSB) between lithologically similar middle- to upper amphibolite-facies rocks on either side.

Recent mapping in the NSB, combined with previous studies, suggest it may represent a graben initially formed during latest Paleozoic transtension contemporaneous with formation of the Narragansett Basin in southeastern MA and RI. Mylonites along the Silver Hill-Wekepeke Fault (Robinson, 1981), bounding the western edge of the NSB, show east-side-down normal motion and west-side down normal motion along the Clinton-Newbury Fault Zone (CNFZ; Goldstein, 1994) which bounds the NSB{\textquoteright}s southeastern margin. A possible extension of the Flint Hill fault system (NH) forms the eastern edge of the NSB offsetting the CNFZ with normal west-side down motion near Ayer, MA. Late brittle normal faults in the NSB are abundant.\ Late, low-To, west-side-down shear zones in the Nashoba Terrane and similar rocks to the south may also be related to down-dropping of the NSB.

AFT ages were collected across north-central MA to constrain its late uplift history. A ~127 Ma AFT age in the NSB is discontinuous with AFT ages in the belts adjoining it, with ~182-144 Ma ages west across the Wekepeke fault and ~160-167 Ma east across the CNFZ. To the west, the brittle southern extension of the Pinnacle Fault in NH (Stodge Meadow Pond fault of Peterson, 1984) follows the western edge of the Fitchburg plutons in MA while a well-exposed west-side down brittle normal fault system, possibly the southward extension of the Campbell Hill Fault (NH), is developed along their eastern edge. AFT ages of ~144-136 Ma immediately west of the Pinnacle Fault in MA are discontinuous with ~117-115 Ma ages immediately to the east within the Fitchburg plutons. A single ~106 Ma age in the plutons west of the Campbell Hill Fault in MA is discontinuous with ~128-123 Ma ages to the east of it. The discontinuities amongst AFT ages across these faults suggest that they may have been active through the Cretaceous.

}, keywords = {$\#$Bibliography, $\#$StaffPubs, AFT, apatite, apatite fission track, brittle, Campbel Hill, Clinton Newbury, Cretaceous, extension, fault, fault zone, fault zones, faults, fission track, Fitchburg, Fitchburg Plutons, Flint Hill, I-290, Johnny Appleseed, Jurassic, merrimack, mesozoic, Nashua Trough, Normal Faults, Oakdale formation, Permian, Pinnacle, Rt 2, Sterling, Stodge Meadow Pond, Triassic, Wachusett, Wekepeke, Worcester Formation}, doi = {10.1130/abs/2016NE-272576}, url = {https://gsa.confex.com/gsa/2016NE/webprogram/Paper272576.html}, author = {Kopera J.P. and Roden-Tice, M.K. and Robert P Wintsch} } @proceedings {268, title = {Age-constraints on fabric reactivation in the Tusas Range, northern New Mexico, using electron-microprobe monazite geochronology; implications for the nature of regional approximately 1400 Ga deformation}, volume = {34}, year = {2002}, note = {Accession Number: 2004-044516; Conference Name: Geological Society of America, 2002 annual meeting; Denver, CO, United States; Conference Date: 20021027; Language: English; Coden: GAAPBC; Collation: 1; Collation: 180; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 200413; Monograph Title: Geological Society of America, 2002 annual meeting; Monograph Author(s): Anonymous; Reviewed Item: Analytic}, month = {2002/10/01/}, pages = {180 - 180}, publisher = {Geological Society of America (GSA) : Boulder, CO, United States}, address = {United States}, abstract = {A key issue in constructing models for the southward growth of Laurentia during the Proterozoic is distinguishing the effects of approximately 1650 Ma and approximately 1400 Ma tectonism. These events share similar styles of deformation and metamorphism, making it difficult to assign structures, fabrics, and metamorphic phases to a particular event. The fundamental geometry of this orogen in the southwestern United States is defined in many areas by fold-fault pairs and isolated synclines of thick approximately 1700 Ma quartzite. In-situ EMP chemical dating of monazite, combined with detailed structural analysis, indicates that such synclines within the Tusas Range of northern New Mexico (locally F (sub 3) ) were substantially modified, if not developed, during approximately 1400 Ma tectonism. Monazite grains from the Ortega quartzite in the central Tusas Range display a shape preferred orientation parallel to the axial-planar fabric of these folds (S (sub 3) ), with overgrowth rims preferentially developed in the X direction of strain. These monazite grains have either >1700 Ma cores or approximately 1650 Ma cores with approximately 1400 Ma overgrowth rims, or are entirely approximately 1400 Ma in age. Field and microstructural observations show that the upright, east-west trending F (sub 3) and S (sub 3) are reactivations of older, northwest-trending fabrics and structures. The presence of approximately 1650 Ma overgrowth rims on monazite grains from the central and northern Tusas Range implies that these folds and fabrics may have nucleated prior to approximately 1400 Ma tectonism. Previous studies have shown an increase in approximately 1400 Ma monazite ages from north to south within the range, consistent with a similar increase in metamorphic grade. This gradient suggests that the central and northern Tusas may have been at progressively shallower crustal levels during approximately 1400 Ma tectonism, thus increasing the preservation of older fabrics, structures, and metamorphic monazite from south to north within the range. These observations support the hypothesis that approximately 1400 Ma tectonism locally reactivated and utilized pre-existing structures and fabrics, but had also profoundly shaped the geometry and metamorphic character of the orogen.}, keywords = {$\#$StaffPubs, dates, deformation, electron probe data, fabric, folds, geochronology, Geochronology 03, geometry, in situ, Laurentia, Mesoproterozoic, metamorphism, monazite, New Mexico, northern New Mexico, orogeny, Ortega Group, overgrowths, phosphates, Precambrian, preferred orientation, proterozoic, reactivation, Southwestern U.S., strain, structural analysis, Structural geology 16, synclines, tectonics, Tusas Mountains, United States, upper Precambrian, zoning}, isbn = {00167592}, url = {http://silk.library.umass.edu/login?url=http://search.ebscohost.com/login.aspx?direct=true\&db=geh\&AN=2004-044516\&site=ehost-live\&scope=site}, author = {Joseph P Kopera and Williams, Michael L. and Jercinovic, Michael J.} } @proceedings {273, title = {Comparison of lineaments with bedrock structures along a cross-strike transect, eastern Massachusetts}, volume = {30}, year = {1998}, note = {Accession Number: 1999-032582; Conference Name: Geological Society of America, 1998 annual meeting; Toronto, ON, Canada; Conference Date: 19981026; Language: English; Coden: GAAPBC; Collation: 1; Collation: 278; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 199912; Monograph Title: Geological Society of America, 1998 annual meeting; Monograph Author(s): Anonymous; Reviewed Item: Analytic}, month = {1998/01/01/}, pages = {278 - 278}, publisher = {Geological Society of America (GSA) : Boulder, CO, United States}, address = {United States}, abstract = {Lineament data derived from three platforms, 1:58,000 color infrared photography (N = 770), 1:80,000 black and white photographs (N = 1106), and 1:250,000 SLAR imagery (N = 521), were used to determine the degree of coincidence between mapped faults and lineaments along a cross strike transect in eastern Massachusetts. The study area extends 27 km in an east-west direction and 8 km north-south and is located along the trace of a tunnel currently being constructed approximately 90 m below grade. Structural data are presently being collected from surface exposures along the tunnel trace and from within the 5 m diameter tunnel bore. These structural data will be compared with lineament data in the future. Reported here are the results of a comparison between the locations of lineaments and the position of major faults mapped on the Bedrock Geologic Map of Massachusetts (1:250,000). Lineaments were first mapped on acetate overlays in two independent trials and compared to determine which lineaments could be reproduced at the same geographic location. Reproducibility results indicate that 21 to 33\% of the lineaments can be reproduced at the same spatial position and are comparable to results obtained from other studies. The length of reproducible lineaments proximal to and approximately parallel with mapped faults was compared with the total length of faults (137 km) within the study area. Results show that a small percentage of the faults are coincident with reproducible lineaments. Three percent of the lengths are mapped by reproducible lineaments observed on the SLAR imagery, 7\% by the 1:80,000 scale photographs, and 5\% by the 1:58,000 color infrared photography. This indicates that 97\%, 93\%, and 95\% of the reproducible lineaments, respectively, are related to other geologic features in the bedrock or nothing at all.}, keywords = {$\#$StaffPubs, aerial photography, BEDROCK, eastern Massachusetts, faults, geophysical surveys, imagery, lineaments, massachusetts, remote sensing, SLAR, Structural geology 16, surveys, tectonics, United States}, isbn = {00167592}, author = {Curry, Patrick J. and Williams, Katherine W. and Stephen B Mabee and Hardcastle, Kenneth C.} } @proceedings {288, title = {Factors influencing groundwater inflows in a newly constructed cross-strike tunnel, eastern Massachusetts; 4, Occurrence and characterization of groundwater inflows}, volume = {31}, year = {1999}, note = {Accession Number: 2001-037345; 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 = {All occurrences of groundwater inflows in a 9 km long, 5-m diameter section of tunnel, 70 to 90 m below grade, were compared with subsurface fracture density, bedrock topography, surface topography, type of surficial deposits, proximity to surface water bodies, and the geographic distribution (domains; Mabee et al., this volume) of surface and subsurface fractures. Subsurface fracture density was calculated for the 320 fractures (through-going fractures) that intersect the entire circumference of the tunnel. Bedrock topography was determined using bore hole data collected during the design phase of the tunnel project. Surface topography is from 1:25,000 scale topographic maps and surficial geology is based on maps of the Framingham and Natick Quadrangles. Seven surface water bodies, primarily brooks and rivers, overlie the tunnel. Five surface fracture domains are based on 1513 fracture measurements collected from 21 outcrops within 3 km of the tunnel. In the tunnel, 413 fractures (all fractures, dips>45 degrees ) comprise seven subsurface fracture domains. High groundwater inflows generally correlate with areas of high subsurface fracture density and where four or more subsurface fracture domains overlap. In addition, high groundwater inflows are also generally located near surface water bodies and below permeable surficial deposits and topographic depressions, especially those with corresponding lows in the bedrock surface. Moreover, subsurface structures which correlate with prominent surface fracture domains produce the highest volume of groundwater inflow. However, not all tunnel sections exhibiting high fracture density and overlapping fracture domains exhibit high groundwater inflows. Also, there is no correlation between areas where two or more surface fracture domains overlap and the volume of groundwater discharging to the tunnel.}, keywords = {$\#$StaffPubs, BEDROCK, boreholes, characterization, design, discharge, eastern Massachusetts, flows, fractures, Framingham Quadrangle, ground water, Hydrogeology 21, massachusetts, movement, Natik Quadrangle, occurrence, outcrops, surface water, topography, tunnels, United States}, isbn = {00167592}, author = {Williams, Katherine W. and Stephen B Mabee and Hardcastle, Kenneth C. and Curry, Patrick J.} } @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 {285, title = {Factors influencing groundwater inflows in a newly constructed cross-strike tunnel, eastern Massachusetts; 1, Lineaments and subsurface structures}, volume = {31}, year = {1999}, note = {Accession Number: 2001-037333; Conference Name: Geological Society of America, 1999 annual meeting; Denver, CO, United States; Conference Date: 19991025; Language: English; Coden: GAAPBC; Collation: 2; Collation: 347-348; 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 = {347 - 348}, publisher = {Geological Society of America (GSA) : Boulder, CO, United States}, address = {United States}, abstract = {Lineaments derived from three platforms; 1:250,000 Side-Looking Airborne Radar (SLAR) images, 1:58,000 Color Infrared (CIR) and 1:80,000 Black and White aerial photographs (BW), were compared to water bearing structures (n = 99) within a 9 km, 70 to 90 meter deep, east-west tunnel being constructed in eastern Massachusetts. Lineaments were drawn by three observers during two independent trials to produce 18 sets of lineaments (n = 9137) covering approximately 1,000 km (super 2) centered over the tunnel. All lineaments for each platform were compared. Three or more overlapping lineaments (azimuths within 5 degrees and within 1 mm at the scale of the imagery) define a single coincident lineament. This analysis generated three sets of coincident lineaments (n = 794), of these 37 cross the tunnel. Buffers were placed around the coincident lineaments at a distance of 1 mm from the center of the lineament at the scale of the platform (e.g. 250 m for the SLAR image). The Mann-Whitney U test was used to determine if the median flow from all tunnel structures which underlie the lineament buffer zones is significantly greater than that of all structures outside of the buffer zones. Results indicate that median flow (11,000 l/day) from structures located within the buffer zones of the BW are significantly greater at the 90\% confidence level than the median flow (5,500 l/day) of structures located outside the buffer zones. No significant differences in flow were found for the other two platforms. Subsurface structures that parallel coincident lineaments (all platforms) and occur within the buffer zones have higher median flow (10,500 l/day) than those structures outside the buffer zones (6,600 l/day). However, this difference is significant at the 70\% confidence level. These results suggest that, in some instances, a thorough lineament analysis can predict water-bearing subsurface structures in poorly exposed, glaciated, metamorphic terrain that has a high degree of suburban development.}, keywords = {$\#$StaffPubs, BEDROCK, eastern Massachusetts, fractures, geophysical surveys, ground water, Hydrogeology 21, lineaments, massachusetts, metamorphic rocks, movement, New England, remote sensing, SLAR, strike, surveys, tectonics, tunnels, United States}, isbn = {00167592}, author = {Curry, Patrick J. and Hardcastle, Kenneth C. and Stephen B Mabee and Williams, Katherine W.} } @proceedings {287, title = {Factors influencing groundwater inflows in a newly constructed cross-strike tunnel, eastern Massachusetts; 3, Surface vs. subsurface fracture characteristics}, volume = {31}, year = {1999}, note = {Accession Number: 2001-037340; 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 = {Major fracture sets (dip >45 degrees ), their geographic distributions (domains), and their characteristics (spacing, trace length, and planarity) were measured in surface outcrops and in a 9 km section of the tunnel (Curry et al., this volume) to determine how well fracture data collected at widely-spaced surface exposures can be extrapolated to a depth of 70 to 90 meters. For the surface fracture data set, fracture sets and domains were determined from 1513 measurements collected at 21 outcrops located within 3 km of the trace of the tunnel. Spacing, trace length, and planarity were determined from scanline measurements (n = 899). For the tunnel data set, 413 fracture measurements were made to determine major sets and domains and a smaller subset (n = 156) was used to estimate fracture characteristics.Five fracture sets (14, 38, 86, 117, and 171) were identified in the outcrops and seven sets (13, 29, 41, 62, 132, 159, and 175) in the tunnel. The 14 and 171 sets correspond well with the 13 and 175 sets in the tunnel. The 38 set observed at the surface includes parts of the 29 and 41 sets in the tunnel. The 86 set does occur in the tunnel but is undersampled because it is aligned with the tunnel. The 62 and 159 sets occur in the tunnel but are not seen at the surface. Although large areas are devoid of outcrops, comparison of surface and subsurface fracture domains indicates that only the 14 and 171 sets show a reasonable overlap with the 13 and 175 domains in the tunnel. These latter sets are the fractures generating most of the groundwater inflow into the tunnel. Median fracture spacing and trace lengths for the 13 and 175 sets in the tunnel are significantly wider and longer than the corresponding 14 and 171 sets at the surface. Fracture planarities showed no significant differences between any of the surface and subsurface fracture sets.}, keywords = {$\#$StaffPubs, BEDROCK, controls, eastern Massachusetts, factors, fractures, ground water, Hydrogeology 21, massachusetts, measurement, movement, New England, outcrops, spatial distribution, tunnels, United States}, isbn = {00167592}, author = {Stephen B Mabee and Williams, Katherine W. and Curry, Patrick J. and Hardcastle, Kenneth C.} } @proceedings {286, title = {Factors influencing groundwater inflows in a newly constructed cross-strike tunnel, eastern Massachusetts; 2, Fracture-supported coincident lineaments and subsurface structures}, volume = {31}, year = {1999}, note = {Accession Number: 2001-037344; 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 = {As part of the evaluation of the ability of lineaments to map subsurface structures, the coincident lineaments which intersect the tunnel (Curry et al., this volume), were evaluated to isolate those lineaments considered to be "fracture-supported". By definition, fracture-supported coincident lineaments are those which parallel nearby surface fracture sets, mapped faults, lithologic contacts, and/or primary ductile structures; features which may be influential to subsurface groundwater flow. Of the 37 coincident lineaments delineated on the three scales of imagery studied, approximately 70\% are considered to be fracture-supported: 9 of the 13 on the 1:58,000 scale images, 10 of 14 on the 1:80,000, and 8 of 10 on the 1:250,000. However, the general lack of surface exposure precludes high confidence in the assignment of fracture-supported status to most lineaments. Large areas devoid of outcrops necessitated extrapolation of regional, surface fracture patterns (domains) to help define some fracture-supported coincident lineaments. There are two occurrences where fracture-supported coincident lineaments from all three scales overlap and are parallel. One occurrence successfully maps the zone of greatest fracture density and highest groundwater inflow (>560 l/min). The other occurrence maps an area of high fracture density and significant subsurface flow (95 l/min). In addition, one other high flow zone (>190 l/min) is mapped by a fracture-supported coincident lineament from the 1:80,000 scale imagery. However, many subsurface fractures and flow zones (<75 l/min) are not mapped by the coincident lineaments regardless of whether or not they are fracture-supported. When considering all fracture-supported coincident lineaments and parallel subsurface structures, the median flow (13,600 l/day) for the mapped structures is greater than the unmapped structures (6,800 liters/day). However, this difference is only significant at the 60\% confidence level.Although the tunnel sections with the greatest fracture density and highest groundwater inflows are successfully mapped by fracture supported coincident lineaments, not all water-bearing zones are delineated.}, keywords = {$\#$StaffPubs, BEDROCK, controls, eastern Massachusetts, factors, fractures, ground water, Hydrogeology 21, imagery, lineaments, massachusetts, movement, New England, outcrops, Structural geology 16, tectonics, tunnels, United States}, isbn = {00167592}, author = {Hardcastle, Kenneth C. and Curry, Patrick J. and Williams, Katherine W. and Stephen B Mabee} } @proceedings {294, title = {Fracture characterization of crystalline bedrock for groundwater investigations; an example from the Marlborough Quadrangle, Massachusetts}, volume = {36}, year = {2004}, note = {Accession Number: 2005-077195; Conference Name: Geological Society of America, Northeastern Section, 38th annual meeting; Geological Society of America, Southeastern Section, 53rd annual meeting; Washington, DC, United States; Conference Date: 20040325; Language: English; Coordinates: N421800N421800W0713000W0713000; Coden: GAAPBC; Collation: 1; Collation: 113; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 200524; Monograph Title: Geological Society of America, Northeastern Section, 38th annual meeting; Geological Society of America, Southeastern Section, 53rd annual meeting; Monograph Author(s): Anonymous; Reviewed Item: Analytic}, month = {2004/03/01/}, pages = {113 - 113}, publisher = {Geological Society of America (GSA) : Boulder, CO, United States}, address = {United States}, abstract = {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.}, keywords = {$\#$StaffPubs, aquifers, Assabet River Fault, BEDROCK, characterization, controls, crystalline rocks, fractured materials, fractures, geographic information systems, ground water, Hydrogeology 21, hydrology, information systems, joints, Marlborough Quadrangle, massachusetts, Middlesex County Massachusetts, permeability, preferential flow, recharge, style, testing, theoretical models, United States}, isbn = {00167592}, url = {https://gsa.confex.com/gsa/2004NE/finalprogram/abstract_70321.htm}, author = {Scott A Salamoff and Stephen B Mabee and Joseph P Kopera and Donald U Wise} } @proceedings {299, title = {Ground truth? Relationship between lineaments and bedrock fabric}, volume = {21}, year = {1989}, note = {Accession Number: 1991-043915; Conference Name: Geological Society of America, 1989 annual meeting; St. Louis, MO, United States; Conference Date: 19891106; Language: English; Coden: GAAPBC; Collation: 1; Collation: A68; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 1991; Monograph Title: Geological Society of America, 1989 annual meeting; Monograph Author(s): Dymek, Robert F. [chairperson]; Shelton, Kevin L. [chairperson]; Reviewed Item: Analytic}, month = {1989/01/01/}, pages = {A68 - A68}, publisher = {Geological Society of America (GSA) : Boulder, CO, United States}, address = {United States}, keywords = {$\#$StaffPubs, aerial photography, BEDROCK, fabric, faults, fractures, granites, ground truth, igneous rocks, joints, lineaments, Maine, orientation, pegmatite, plutonic rocks, quartz veins, SLAR, structural analysis, Structural geology, Structural geology 16, United States, veins}, isbn = {00167592}, author = {Stephen B Mabee and Hardcastle, Kenneth C. and Donald U Wise} } @proceedings {306, title = {Landslides from Tropical Storm Irene in the Deerfield Watershed, western Massachusetts}, volume = {45}, year = {2013}, note = {Accession Number: 2014-027064; Conference Name: Geological Society of America, Northeastern Section, 48th annual meeting; Bretton Woods, NH, United States; Conference Date: 20130318; Language: English; Coordinates: N411500N425500W0695500W0733000; Coden: GAAPBC; Collation: 2; Collation: 83-84; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 201417; Monograph Title: Geological Society of America, Northeastern Section, 48th annual meeting; Monograph Author(s): Anonymous; Reviewed Item: Analytic}, month = {2013/02/01/}, pages = {83 - 84}, publisher = {Geological Society of America (GSA) : Boulder, CO, United States}, address = {United States}, abstract = {Four landslides (3 translational debris flows and 1 rotational slide) occurred along the Cold River within the Deerfield River watershed (1440 km (super 2) ) in northwestern Massachusetts closing a six mile section of Route 2, a major east-west transportation corridor, for 3.5 months. These are among the largest landslides to occur in Massachusetts since 1901. Tropical storm Irene dropped 180-250+ mm of rain in a 12 to 15-hour period on the Deerfield watershed preceded by 130-180 mm of rain in the 1.5 weeks leading up to Irene. Soils were saturated, an unusual condition for the month of August, and probably contributed significantly to slope failure. The three translational slides occurred at approximately 10 am on August 28, 2011, involved 765 m of slope at an average angle of 28-33 degrees , covered an area of 1.2 ha and moved about 7645 m (super 3) of material. Bedrock sheeting joints oriented parallel to the slope (284 degrees , 38-40 degrees dip) provided the slip surface upon which the overlying 0.6-1.2 m of colluvium and glacial till slid. The rotational slide occurred along an unarmored section of the Cold River. The slip surface was a 4-8 foot thick layer of laminated lake-bottom sediments overlain by 12-19 feet of stream terrace and debris flow/alluvial fan deposits transported by Trout Brook, a smaller tributary to the Cold River. This section of Route 2 has experienced chronic failures beginning with the storm of 1938. The cost to repair this six-mile section of Route 2 was $22.5 million. Flooding within the Deerfield watershed was extreme with a record-breaking peak flow of 3100 m (super 3) /s (72 year record) where the Deerfield enters the Connecticut River. Approximately 1.6x10 (super 8) m (super 3) of water was discharged through the Deerfield during the event indicating that approximately 112 mm of Irene{\textquoteright}s rainfall was converted directly to runoff, a yield of between 45\% and 62\%. Clays and silts locked in storage in the glacial sediments within the watershed were mobilized resulting in record-breaking sediment loads 5-times greater than predicted from the pre-existing rating curve. Approximately 1.2 Mtonnes of sediment was discharged by the river during Irene. Where the Deerfield and Connecticut Rivers meet, the Deerfield watershed area is one tenth the size of the Connecticut River, yet the Deerfield produced as much as 40\% of the total sediment observed on the lower Connecticut.}, keywords = {$\#$Landslides, $\#$NaturalHazards, $\#$StaffPubs, Cold River, Deerfield Watershed, effects, Environmental geology, geologic hazards, Irene, landslide, landslides, mass movements, massachusetts, natural hazards, storms, Tropical Storm Irene, United States, western Massachusetts}, isbn = {00167592}, url = {https://gsa.confex.com/gsa/2013NE/webprogram/Paper215998.html}, author = {Stephen B Mabee and Jonathan D Woodruff and Fellows, John and Joseph P Kopera} } @proceedings {320, title = {Subtle modification of glacially derived materials along Massachusetts{\textquoteright} southern coast by passing summer storms}, volume = {47}, year = {2015}, pages = {136}, publisher = {Geological Society of America (GSA) : Boulder, CO, United States}, edition = {3}, address = {Northeastern Section - 50th Annual Meeting (23{\textendash}25 March 2015), Bretton Woods, NH}, abstract = {Engineered resupply of sand to coastal environments, i.e. nourishment, offers an attractive short-term strategy to address beach erosion in Massachusetts. For efficient nourishment, site-specific knowledge of seasonal grain size and sediment volume variability at eroding beaches is essential. We have begun measuring grain size and profile at 22 eroding Massachusetts beaches, capturing summer and winter conditions at each site through four to nine representative transects perpendicular to the shore and spaced 100-500 meters apart. Our recently completed first summer field season (August/September 2014) visited eight beaches along Massachusetts{\textquoteright} south coast from Rhode Island to Nantucket. These environments should reflect regional glacial history and a summer interval of reduced storm activity. Where unstratified surficial materials characterize the coast, erosion of glacial till (Horseneck and East beaches, Westport) and end moraine (Barges Beach, Cuttyhunk Island; Town and Sylvia State beaches, Oak Bluffs/Edgartown) can yield cobble berms capping steep intertidal zones. We noted that increased wave activity during storms strips a thin (inches-thick) layer of intertidal sand to reveal gravel and cobble below, while leaving beach profile essentially unchanged. In contrast, where (cobble-free) glacial outwash intersects the coast (Surf Beach, Falmouth; Miacomet and Low beaches, Nantucket) sand and gravel are distributed more evenly across beach facies. Here passing summer storms modify beach profile but not grain size: high surf cuts sandy berms, shifting steepened intertidal zones landward. We will reoccupy south coast sites at the end of winter in 2015 to examine effects of seasonally related increase in storm (and wave) activity. Survey of Massachusetts{\textquoteright} east coast (Sandwich to New Hampshire) is planned for summer of 2015 and winter of 2016. Additionally, overwash sequences recovered through backbarrier basin coring at selected sites complement our beach survey by providing depositional records of particularly strong storms. Study results will allow identification of suitably matched nourishment sources onshore, or offshore, as described in Massachusetts{\textquoteright} Office of Coastal Zone Management{\textquoteright}s extensive grain-size database. }, keywords = {$\#$StaffPubs, Barges Beach, beach, beach erosion, beach profile, BOEM, Buzzard{\textquoteright}s Bay, climate change, coast, coastal, cobble, Cuttyhunk Island, dune, East beach, Edgartown, erosion, Falmouth, grain-size, Horseneck beach, intertidal, Low beach, Martha{\textquoteright}s Vineyard, Miacomet beach, Nantucket, nourishment, Oak Bluffs, offshore, onshore, Plum Island, profiles, sand, sea level rise, storm, Surf Beach, Sylvia State beaches, Town beach, Westport, winter storm}, url = {https://gsa.confex.com/gsa/2015NE/webprogram/Paper252510.html}, author = {Nicholas L Venti and Sabina Gessay and Paul Southard and Douglass Beach and Margot Mansfield and Stephen B Mabee and Jonathan D Woodruff} } @article {277, title = {Correlation of lineaments and bedrock fracture fabric; implications for regional fractured-bedrock aquifer studies, preliminary results from Georgetown, Maine}, journal = {Ground Water Management}, volume = {3}, year = {1990}, note = {Accession Number: 1991-010604; Conference Name: FOCUS conference on Eastern regional ground water issues; Springfield, MA, United States; Conference Date: 19901017; Language: English; Collation: 15; Collation: 283-297; Publication Types: Serial; Conference document; Updated Code: 1991; Illustration(s): illus. incl. 2 tables, sketch maps; Number of References: 15; Monograph Title: Proceedings of the FOCUS conference on Eastern regional ground water issues; Monograph Author(s): Anonymous; Reviewed Item: Analytic}, month = {1990/01/01/}, pages = {283 - 297}, publisher = {Water Well Journal Pub. Co. : Dublin, OH, United States}, address = {United States}, keywords = {$\#$StaffPubs, aquifers, fractured materials, fractures, geophysical surveys, Georgetown Maine, ground water, hydrogeology, Hydrogeology 21, imagery, Maine, remote sensing, Sagadahoc County Maine, SLAR, surveys, United States}, isbn = {10479023}, url = {http://info.ngwa.org/gwol/pdf/900156672.PDF}, author = {Stephen B Mabee and Hardcastle, Kenneth C. and Donald U Wise} } @article {305, title = {Influence of rock fabric on fracture attribute distribution and implications for groundwater flow in the Nashoba Terrane, eastern Massachusetts}, journal = {Journal of Structural Geology}, volume = {30}, year = {2008}, note = {Accession Number: 2009-050694; Language: English; Coden: JSGEDY; Collation: 14; Publication Types: Serial; Updated Code: 200928; Reviewed Item: Analytic}, month = {2008/04/01/}, pages = {464 - 477}, publisher = {Elsevier : Oxford, International}, address = {International}, abstract = {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.}, keywords = {$\#$StaffPubs, foliation, fractures, ground water, Hydrogeology 21, joints, massachusetts, movement, Nashoba terrane, preferred orientation, statistical distribution, structural analysis, Structural geology, style, terranes, United States}, isbn = {01918141}, url = {http://www.sciencedirect.com/science/article/pii/S0191814107002362}, author = {Alex K Manda and Stephen B Mabee and Donald U Wise} } @article {265, title = {A method of collecting and analyzing lineaments for regional-scale fractured-bedrock aquifer studies}, journal = {Ground Water}, volume = {32}, year = {1994}, note = {Accession Number: 1996-036299; Language: English; Coordinates: N435500N435500W0691000W0691000; Coden: GRWAAP; Collation: 11; Publication Types: Serial; Updated Code: 199612; Illustration(s): illus.; Number of References: 20; Reviewed Item: Analytic}, month = {1994/12/01/}, pages = {884 - 894}, publisher = {National Water Well Association, Ground-Water Technology Division : Urbana, IL, United States}, address = {United States}, abstract = {A new method is proposed for collecting and reducing large collections of lineament data. The method consists of three steps: (1) collection of lineament data using multiple observers, multiple observation trials, and several types of imagery; (2) reproducibility tests; and (3) domain overlap analysis. Collection of lineament data and reproducibility tests are performed by overlaying lineament maps drawn by several observers or by superimposing multiple maps prepared by a single observer and identifying lineaments which are coincident (coincident lineaments = lineaments that have azimuths within 5 {\textpm} and separation distances are within 1{\textendash}2 mm at the scale of drawing). Domain overlap analysis is accomplished by measuring the trends of near-vertical fractures at outcrops distributed over the study region and comparing the spatial distribution of these trends with similar-trending coincident lineaments. Lineaments that are not reproducible and are not geographically correlative with fractures are considered unimportant and removed from the data base. The method was applied to a 44 km2 study area in Maine and resulted in a reduction in the lineament data base from 6500 to 217. Transmissivities determined for bedrock wells located within 30 meters of lineaments that are both reproducible and geographically correlative with outcrop-scale fractures are generally higher than the transmissivities of wells located near lineaments that are not separated on the basis of these criteria. Application of the method serves as an important filter by providing a more manageable lineament data base from which to begin detailed field checking and/or geophysical surveys directed toward specific lineaments.}, keywords = {$\#$StaffPubs, aquifers, BEDROCK, coastal environment, fractured materials, Georgetown Island, ground water, Hydrogeology 21, Knox County Maine, lineaments, Maine, mapping, mathematical methods, processes, tectonics, United States}, isbn = {0017467X}, url = {http://onlinelibrary.wiley.com/doi/10.1111/j.1745-6584.1994.tb00928.x/abstract}, author = {Stephen B Mabee and Hardcastle, Kenneth C. and Donald U Wise} } @article {309, title = {Microprobe monazite geochronology; new refinements and new tectonic applications}, journal = {Abstracts with Programs - Geological Society of America}, volume = {35}, year = {2003}, note = {Accession Number: 2004-076942; Conference Name: Geological Society of America, Northeastern Section, 38th annual meeting; Halifax, NS, Canada; Conference Date: 20030327; Language: English; Coden: GAAPBC; Collation: 2; Collation: 22-23; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 200422; Monograph Title: Geological Society of America, Northeastern Section, 38th annual meeting; Monograph Author(s): Anonymous; Reviewed Item: Analytic}, month = {2003/03/01/}, pages = {22 - 23}, publisher = {Geological Society of America (GSA) : Boulder, CO, United States}, address = {United States}, abstract = {

High-resolution compositional mapping and dating of monazite on the electron microprobe is a powerful addition to microstructural and petrologic analysis and an important tool for tectonic studies. Its in-situ nature and high spatial resolution offer an entirely new level of structurally and texturally specific geochronologic data that can be used to put absolute time constraints on P-T-D paths, constrain the rates of sedimentary, metamorphic, and deformational processes, and provide new links between metamorphism and deformation. New analytical techniques have significantly improved the precision and accuracy of the technique and new mapping and image analysis techniques have increased the efficiency and strengthened the correlation with fabrics and textures. Microprobe geochronology is particularly applicable to three persistent microstructural-microtextural problem areas: (1) constraining the chronology of metamorphic assemblages; (2) constraining the timing of deformational fabrics; and (3) interpreting other geochronological results. In addition, authigenic monazite can be used to date sedimentary basins, and detrital monazite can fingerprint sedimentary source areas, both critical for tectonic analysis. Although some monazite generations can be directly tied to metamorphism or deformation, at present, the most common constraints rely on monazite inclusion relations in porphyroblasts that, in turn, can be tied to the deformation and/or metamorphic history. Microprobe mapping and dating allow geochronology to be incorporated into the routine microstructural analytical process, resulting in a new level of integration of time (t) into P-T-D histories. The Legs Lake exhumational shear zone in Saskatchewan is a classic example. Monazite can be tied to decompressional metamorphic reactions in the upper plate and to prograde reactions and shear fabrics in the footwall, firmly constraining the timing of regional exhumations with a long multiphase tectonic history.

}, keywords = {$\#$StaffPubs, age;, electron probe data;, geochronology;, Geochronology; 03, Igneous and metamorphic petrology; 05A, metamorphic rocks;, metamorphism;, methods;, monazite;, P-T-t paths;, phosphates;}, isbn = {00167592}, url = {http://silk.library.umass.edu/login?url=http://search.ebscohost.com/login.aspx?direct=true\&db=geh\&AN=2004-076942\&site=ehost-live\&scope=site}, author = {Williams, Michael L. and Jercinovic, Michael J. and Mahan, Kevin and Joseph P Kopera} } @article {310, title = {Monazite geochronology of Proterozoic quartzites; a powerful tool for understanding reactivation of continental lithosphere in the Southwestern United States}, journal = {Abstracts with Programs - Geological Society of America}, volume = {34}, year = {2002}, note = {Accession Number: 2004-069830; Conference Name: Geological Society of America, Northeastern Section, 37th annual meeting; Springfield, MA, United States; Conference Date: 20020325; Language: English; Coden: GAAPBC; Collation: 1; Collation: 26; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 200421; Monograph Title: Geological Society of America, Northeastern Section, 37th annual meeting; Monograph Author(s): Anonymous; Reviewed Item: Analytic}, month = {2002/03/01/}, pages = {26 - 26}, publisher = {Geological Society of America (GSA) : Boulder, CO, United States}, address = {United States}, abstract = {

The influence of approximately 1.65 vs. 1.4 Ga tectonism on the evolution of the Proterozoic orogenic belt in the southwestern United States has been an issue of considerable debate. This belt was assembled at approximately 1.75-1.65 Ga, but recent work has highlighted a significant reactivation of the orogen at 1.4 Ga. The discovery of abundant monazite in regionally extensive, 1-2 km thick quartzites found throughout the orogenic belt may provide important new constraints on its tectonic history. These quartzites define the present regional geometry of exposed Proterozoic rocks and are believed to strongly influence local structure. Preliminary results of in-situ microprobe dating of monazite from the Ortega Quartzite in the Tusas Mountains in northern New Mexico suggest an increasing influence of 1.4 Ga tectonism from north to south within the range. Monazite from the Jawbone Syncline within northernmost part of the range consistently yields ages of 1.75 to 1.72 Ga. These monazite grains are interpreted to be mostly detrital in origin, with REE and age zoning reflecting the history of the source terranes. Monazite from an anticline immediately to the south has 1.72-1.75 Ga detrital cores with 1.67-1.68 Ga rims, implying that initial fold formation occurred during the approximately 1.67-1.65 Ga Mazatzal Orogeny. Monazite from the middle and southern Tusas Mountains is predominantly 1.4 Ga in age. This suggests that a previously documented gradient in deformation and metamorphism from north to south may reflect a multistage tectonic history for the range, with an increasingly intense overprint of 1.4 Ga tectonism to the south. Monazite has also been found in several Proterozoic quartzites in Colorado, allowing the possibility to compare and correlate deformation and metamorphism across the region. Monazite dating in thick quartzites represents a powerful tool by which the effects of approximately 1.65 and 1.4 Ga tectonism can be separated, leading to a better understanding of the evolution and stabilization of Proterozoic crust in the southwestern United States and may be an important new technique in deconvoluting the tectonic histories of other orogenic belts.

}, keywords = {$\#$StaffPubs, absolute age;, continental lithosphere;, crust;, deformation;, Geochronology; 03, Jawbone Syncline;, lithosphere;, Mazatzal Orogeny;, metamorphic rocks;, metamorphism;, monazite;, New Mexico;, orogeny;, Paleoproterozoic;, phosphates;, Precambrian;, Proterozoic;, quartzites;, Southwestern U.S.;, tectonics;, Tusas Mountains;, United States;, upper Precambrian;}, isbn = {00167592}, url = {http://silk.library.umass.edu/login?url=http://search.ebscohost.com/login.aspx?direct=true\&db=geh\&AN=2004-069830\&site=ehost-live\&scope=site}, author = {Joseph P Kopera and Williams, Michael L. and Jercinovic, Michael J.} } @article {311, title = {Monazite geochronology of the Ortega Quartzite: documenting the extent of 1.4 Ga tectonism in northern New Mexico and across the orogen}, journal = {Abstracts with Programs - Geological Society of America}, volume = {34}, year = {2002}, note = {Accession Number: 2003-041318; Conference Name: Geological Society of America, Rocky Mountain Section, 54th annual meeting; Cedar City, UT, United States; Conference Date: 20020507; Language: English; Coden: GAAPBC; Collation: 1; Collation: 10; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 200313; Monograph Title: Geological Society of America, Rocky Mountain Section, 54th annual meeting; Monograph Author(s): Anonymous; Reviewed Item: Analytic}, month = {2002/04/01/}, pages = {10 - 10}, publisher = {Geological Society of America (GSA) : Boulder, CO, United States}, address = {United States}, abstract = {

Preliminary results of in-situ microprobe dating of monazite from the Ortega Quartzite suggest an increasing influence of 1.4 Ga tectonism from north to south within the in the Tusas Mountains of northern New Mexico. Monazite from the Jawbone Syncline within northernmost part of the range consistently yields ages of 1.75 to 1.72 Ga. These monazite grains are interpreted to be mostly detrital in origin, with REE and age zoning reflecting the history of the source terranes. Monazite from an anticline immediately to the south has 1.72-1.75 Ga detrital cores with 1.67-1.68 Ga rims, implying that initial fold formation occurred during the approximately 1.67-1.65 Ga Mazatzal Orogeny. Monazite from the middle and southern Tusas Mountains is predominantly 1.4 Ga in age. This suggests that a previously documented gradient in deformation and metamorphism from north to south may reflect a multistage tectonic history for the range, with an increasingly intense overprint of 1.4 Ga tectonism to the south. The discovery of abundant monazite in regionally extensive, 1-2 km thick quartzites found throughout the Proterozoic orogenic belt of the southwestern United States may provide important new constraints on the region{\textquoteright}s tectonic history, specifically, the extent and influence of 1.4 Ga tectonism on the formation and modification of fundamental large-scale structures. These quartzites define the present regional geometry of exposed rocks within the Proterozoic Mazatzal Province, and are believed to strongly influence local structure. In addition to northern New Mexico, monazite has also been found in several Proterozoic quartzites in Colorado, allowing the possibility to compare and correlate deformation and metamorphism across the region. Monazite dating in thick quartzites represents a powerful tool by which we can better understand the evolution and stabilization of Proterozoic crust in the southwestern United States, and may be an important new technique in deconvoluting the tectonic histories of other orogenic belts.

}, keywords = {$\#$StaffPubs, anticline, deformation;, folds;, monazite;, New Mexico;, orogeny;, Ortega Group;, phosphates;, Precambrian;, Proterozoic;, Structural geology; 16, tectonics;, Tusas Mountains;, United States;, upper Precambrian;}, isbn = {00167592}, url = {http://silk.library.umass.edu/login?url=http://search.ebscohost.com/login.aspx?direct=true\&db=geh\&AN=2003-041318\&site=ehost-live\&scope=site}, author = {Joseph P Kopera and Williams, Michael L. and Jercinovic, Michael J.} } @article {312, title = {Monazite geochronology of the Proterozoic Ortega Quartzite; documenting the extent of 1.4 Ga tectonism in the Tusas Range and beyond}, journal = {New Mexico Geology}, volume = {24}, year = {2002}, note = {Accession Number: 2004-009303; Conference Name: New Mexico Geological Society spring meeting; Socorro, NM, United States; Conference Date: 20020405; Language: English; Coden: NMGED2; Collation: 1; Collation: 59; Publication Types: Abstract Only; Serial; Conference document; Updated Code: 200403; Monograph Title: New Mexico Geological Society spring meeting; abstracts; Monograph Author(s): Anonymous; Reviewed Item: Analytic}, month = {2002/05/01/}, pages = {59 - 59}, publisher = {New Mexico Bureau of Mines and Mineral Resources : Socorro, NM, United States}, address = {United States}, keywords = {$\#$StaffPubs, absolute age;, dates;, deformation;, electron probe data;, geochronology;, Geochronology; 03, ion probe data;, mass spectra;, metamorphic rocks;, metamorphism;, monazite;, New Mexico;, orogeny;, Ortega Group;, phosphates;, Precambrian;, Proterozoic;, quartzites;, spectra;, Structural geology; 16, tectonics;, Tusas Mountains;, United States;, upper Precambrian;}, isbn = {0196948X}, url = {http://silk.library.umass.edu/login?url=http://search.ebscohost.com/login.aspx?direct=true\&db=geh\&AN=2004-009303\&site=ehost-live\&scope=site}, author = {Joseph P Kopera and Williams, Michael L. and Jercinovic, Michael J.} } @Map {28, title = {Bedrock Geologic Map of Massachusetts}, year = {1983}, publisher = {United States Geological Survey}, abstract = {

(Zen et al., 1983) The 1:250,000 scale Bedrock Geologic Map of Massachusetts, published by the USGS in 1983, shows the distribution of the different rock units, faults, and other features that make up the bedrock of Massachusetts. It was compiled from published 1:24,000-scale maps., unpublished data, and field reconnaissance by the authors. Many areas of the state, however, have yet to be mapped thoroughly at 1:24,000 scale. A paper version can be ordered from the USGS Store (http://store.usgs.gov/) by searching for Product Number: 32370 or by clicking the links below. A two-volume text, The Bedrock Geology of Massachusetts, published in 1991, accompanies the map. The publication is catalogued as U.S. Geological Survey Professional Paper 1366 A-D (western Mass.) and 1366 E-J (eastern Mass.)

A variety of ways to download the map and text are listed in "Other Links" below.

}, keywords = {$\#$MassGeology, $\#$MassGeologyMap, $\#$StateGeologicMap, bedrock geology, eastern MA, GEOLOGIC MAP, GEOLOGY, map, massachusetts, western MA}, issn = {978-0-607-82552-7}, url = {http://ngmdb.usgs.gov/Prodesc/proddesc_16357.htm}, author = {Zen, E-an and Goldsmith, Richard and Ratcliffe, Nicholas M and Robinson, P and Stanley, Rolfe S and Hatch, Norman L and Shride, Andrew F and Weed, Elaine G A and Wones, David R} } @Map {220, title = {[Digital Conversion] Bedrock geologic map of the Gloucester and Rockport quadrangles, Massachusetts}, year = {2007}, publisher = {Massachusetts Geological Survey}, edition = {DC-07-01}, abstract = {

Digitized version of\ U.S. Geological Survey Miscellaneous Investigations Series Map I-2285

}, keywords = {$\#$BedrockMaps, $\#$MGSPub, Cape Anne granite, Essex, Gloucester, granite, Ipswich, Manchester, MGS Publication, pluton, quarry, Rockport}, author = {Dennen W. and Fernandez M.} } @Map {249, title = {Onshore-offshore surficial geologic map of the Provincetown Quadrangle, Barnstable County, Massachusetts}, year = {2012}, publisher = {Massachusetts Geological Survey}, edition = {OFR12-01}, abstract = {Undergoing Editing and Review. Please contact sbmabee[at]geo[dot]umass[dot]edu for latest version.}, keywords = {$\#$MGSPub, $\#$OnshoreOffshore, $\#$SurficialMaps, Cape Cod, coastal, glacial, offshore, onshore, Provincetown, surficial, Truro}, author = {Borrelli, M. and Gontz, A.M. and Wilson, J.R. and Brown, T.L.B. and Norton, A.R. and and G S Geise} } @Map {245, title = {Preliminary bedrock geologic map of the Westford quadrangle, Massachusetts}, year = {2009}, publisher = {Massachusetts Geological Survey}, edition = {OFR-09-01}, abstract = {Bedrock Geologic Map contains brittle fracture data Mapping still in progress. For interim fracture database, please contact Joe Kopera }, keywords = {$\#$BedrockMaps, $\#$MGSPub, Acton, amphibolite, ayer granite, Berwick formation, Boxborough, calc-silicates, Carlisle, Chelmsford, chelmsford granite, Clinton-Newbury Fault, Concord, diorite, gneiss, Groton, LITTLETON, magnetite, marble, migmatite, Nashoba Formation, phyllonite, tadmuck brook schist, Tyngsborough, Westford}, author = {Joseph P Kopera and D.C. Alvord and Richard H Jahns and M.E. Willard and W.S. White} } @Map {253, title = {Progress map of the onshore-offshore surficial geologic map of the North Truro quadrangle, Barnstable County, Massachusetts}, publisher = {Massachusetts Geological Survey}, edition = {OFR13-01}, abstract = {Map undergoing editing and review. Please contact sbmabee@geo.umass.edu for a copy.}, keywords = {$\#$MGSPub, $\#$OnshoreOffshore, $\#$SurficialMaps, Cape Cod, dunes, glacial, offshore, onshore, onshore-offshore, Pleistocene, surficial, Truro}, author = {Borrelli, M. and Gontz, A.M. and Smith, T.L. and Wilson, J.R. and Shumchenia, E.J. and and G S Geise} } @techreport {260, title = {Preliminary Geology and Assessment of Groundwater Potential at Cresta de Sacramento, Palpa, Peru: Field Report {\textendash} July 2002}, year = {2003}, pages = {31}, abstract = {

31 pages contact sbmabee @geo.umass.edu

}, keywords = {$\#$StaffPubs, aquifer, Atacama Desert, groundwater, lineament, Nazca lines, Peru}, author = {Donald U Wise and Stephen B Mabee and Hardcastle, K.C.} }