%0 Conference Proceedings %B Geological Society of America Abstracts with Programs %D 2015 %T The Nashoba Terrane: A new tectonostratigraphy and shared structural styles with the Merrimack belt in Massachusetts %A Joseph P Kopera %K #StaffPubs %K acadian %K alleghenian %K amphibolite facies %K chlorite %K deformation %K eastern Massachusetts %K fabric %K folds %K Harvard Conglomerate %K Hudson %K merrimack %K Merrimack Belt %K nashoba %K Nashoba terrane %K nashua %K Nashua Trough %K pin hill %K Structural geology %K tectonic history %K tectonostratigraphy %X Recent STATEMAP-sponsored geologic mapping of several 7.5' quadrangles in east-central Massachusetts describe a new tectonostratigraphy and structural history for migmatitic gneisses of the Cambro-Ordivician arc complex represented, in part, by the Nashoba Formation. While preserved sedimentary structures are absent, four discrete subunits can be mapped based on distinct lithologies. From structurally lowest to highest, they are: A felsic magnetite-bearing bt gneiss, a magnetite and silliminite rich mu-bearing bt paragneiss, gt-bearing sulfidic bt-gneisses interlayered with sulfidic schist, amphibolite, and marble, and a calc-silicate rich bt-gneiss. The Nashoba terrane exhibits near-identical early and late styles of deformation to those in the adjacent Nashua sub-belt of the Merrimack terrane: Early amphibolite-facies isoclinal folding (D1) overprinted by tight upright folding (D2) and associated thrust faults define the map-scale geometry of tectonostratigraphic units between the two terranes. D2 occurred syn-peak upper amphibolite facies metamorphism in the Nashoba terrane while defined by retrograde greenschist facies fabrics in the Merrimack terrane. These are overprinted by outcrop-scale sinistral strike-slip motion (D3) in the Nashoba terrane progressively transitioning to late chlorite-grade NW-side down oblique extension (D4) exhibited in both terranes. Correlation of the above sequence with existing geochronology, structural petrology, and tectonic studies by other workers in the area suggest that D1 in both terranes occurred prior to and/or during ~370 Ma Acadian orogenesis. Existing geochronology shows D2 fold and fabric development to be diachronous both within and across terranes: occurring both before and after ~363 Ma, with progressive development possibly as late as ~325 Ma, in the Nashoba terrane. D2 in the Nashua sub-belt of the Merrimack terrane occurs after ~330 Ma in the Carboniferous, as late at ~293 Ma in the Permian, during Alleghenian orogenesis. NW-side-down extension and associated rotation of M1 metamorphic isograds in the Merrimack Terrane, and exhumation of the Nashoba terrane, are generally accepted to have occurred during later stages of Alleghenian orogenesis in the Permian. %B Geological Society of America Abstracts with Programs %7 3 %I Geological Society of America (GSA) : Boulder, CO, United States %C Northeastern Section - 50th Annual Meeting (23–25 March 2015), Bretton Woods, NH %V 47 %P 42 %8 03/2015 %G eng %U https://gsa.confex.com/gsa/2015NE/webprogram/Paper253009.html %0 Conference Proceedings %B Abstracts with Programs - Geological Society of America %D 2006 %T A new way of looking at, and mapping, bedrock; the hydrostructural domain map of the Ayer Quadrangle, northeastern Massachusetts %A Joseph P Kopera %A Stephen B Mabee %K #StaffPubs %K aquifers %K Ayer Quadrangle %K BEDROCK %K faults %K foliation %K fracture zones %K fractures %K ground water %K Hydrogeology 21 %K joints %K mapping %K massachusetts %K measurement %K Merrimack Belt %K movement %K Nashoba terrane %K northeastern Massachusetts %K observations %K orientation %K physical properties %K recharge %K shear zones %K Structural geology 16 %K style %K United States %X While traditional bedrock geologic maps contain valuable information, they commonly lack data on fractures and physical properties of the rock. The increased need for better understanding of groundwater behavior in bedrock aquifers has made this data critical. Hydrostructural domain maps reclassify bedrock based on fracture systems and physical properties that may have implications for groundwater flow and recharge. These maps are constructed from detailed field observations and measurements of 2000-3000 fractures from 60-70 stations across a 7.5' quadrangle. Hydrostructural domains are displayed on the map as traditional lithologic units would be, with detailed descriptions and photos of the fracture characteristics and physical properties of each hydrostructural "unit". In the Ayer Quadrangle, such domains closely correspond with bedrock lithology and ductile structural history. Steeply dipping metasedimentary rocks of the Merrimack Belt have pervasive, closely spaced, throughgoing fractures developed parallel to foliation, and therefore provide an excellent potential for vertical recharge. Where these rocks are intensely cut by a strong subhorizontal cleavage, a parallel fracture set dominates providing an opportunity for lateral flow. Massive granites generally have a well developed, widely-spaced orthogonal network of fracture zones which may provide excellent local recharge. High-grade gneisses of the Nashoba Terrane have poorly developed fracture sets except near regional shear zones, where foliation parallel fractures and cross-joints may provide good vertical recharge and provide a strong northeast trending flow anisotropy. These maps are intended to provide a regional-scale information to assist in site-specific groundwater investigations. We believe that such maps are an example of how new types of geologic maps can, and must, be developed to address changing societal needs. %B Abstracts with Programs - Geological Society of America %I Geological Society of America (GSA) : Boulder, CO, United States %C United States %V 38 %P 166 - 166 %8 2006/10/01/ %@ 00167592 %G eng %U https://gsa.confex.com/gsa/2006AM/finalprogram/abstract_116561.htm %N 77 %! Abstracts with Programs - Geological Society of America %0 Online Database %D 0 %T National Geologic Map Database %K #BedrockMaps %K #SurficialMaps %K bedrock geology %K geologic maps %K map %K surficial geology %X

This database houses almost all geologic maps produced by the USGS, and links to almost all maps published by state geologic surveys, including the MGS.

Searching by placename is currenty disabled, but an interactive web-map interface to the NGMDB can be found here:

http://mrdata.usgs.gov/geology/state/map.html?x=-71.8089194224132&y=42.2562234015901&z=8


It is also recommended you find the name of the USGS 7.5' topographic quadrangle your town is in by looking at the DEP Hydrogeologic Information Matrix, and searching the database for that. It is also very useful to search the USGS Publication Warehouse as well for the quadrangle you want.

%I United States Geological Survey, Association of American State Geologists %G eng %U http://ngmdb.usgs.gov %0 Generic %D %T NASA WorldWind %K #GISSoftware %K #MapsDataPublications %K GIS software %K landsat %K NASA %K remote sensing %X World Wind is an open-source (released under the NOSA license) virtual globe developed by NASA and the open source community for use on personal computers. %I NASA %G eng %U http://worldwind.arc.nasa.gov/ %0 Generic %D %T National Earth Science Education Standards %K #EducationalResources %K #EducationStandards %K activities %K classroom %K content %K curricula %K earth science %K education %K K-12 %K lesson plans %K schools %K standards %K teacher resources %K teaching %X Standards for K-12 Earth Science Curricula and resources for Earth Science teachers. %I Kentucky Geological Survey %G eng %U http://www.uky.edu/KGS/education/edustand.htm %0 Generic %D 0 %T National Earthquake Information Center, Earthquake Hazards Program %K earthquakes %K massachusetts %K natural hazards %G eng %U http://earthquake.usgs.gov/regional/states.php?regionID=21®ion=Massachusetts %1

Massachusetts earthquake information from the USGS.

%0 Generic %D 0 %T National Geodetic Survey Data Explorer %K #MapsDataPublications %K #Misc %K #Topo %K benchmarks %K coast %K geodesy %K geodetic %K survey %K surveying %K topography %X

Use this web map service to find locations of all NCGS geodetic and survey benchmarks.  A great resource!

%G eng %U http://www.ngs.noaa.gov/NGSDataExplorer/ %0 Generic %D %T National Geologic Map Database %K #MapDatabase %K #MapsDataPublications %K catalog %K data %K database %K GEOLOGIC MAP %K index %K maps %X Search here first for any and all geologic map data for the Commonwealth before searching the links below. %I USGS %G eng %U http://ngmdb.usgs.gov/ %0 Generic %D 0 %T National Park Service Teacher Resources %K #EducationalResources %K #Fieldtrips %K #SubjectResources %K activities %K classroom %K curricula %K earth science %K education %K GEOLOGY %K groundwater %K K-12 %K lesson plans %K national parks %K parks %K schools %K standards %K teacher resources %K teaching %K water %K water cycle %X Educational resources and links for teaching geology with examples from the National Parks %I NPS %G eng %U http://www2.nature.nps.gov/geology/education/index.cfm %0 Generic %D 0 %T National Science Education Standards %K earth science education standards %K education %K educational resources %I Kentucky Geological Survey %G eng %U http://www.uky.edu/KGS/education/edustand.htm %0 Generic %D %T NEIGC Fieldtrip guidebooks for various parts of New England %K #EducationalResources %K #Fieldtrips %K #LegacyPublications %K #MapsDataPublications %K field trip %K geologic history %K guide %K guidebook %K New England %K sites %K visit %X Guidebooks form the New England Intercollegiate Geological Conference NEIGC conference publications are and will continue to be the best resource for New England geology. %I Salem State %G eng %U http://w3.salemstate.edu/ lhanson/NEIGC/Guidebooks.html %0 Generic %D %T NeMO Explorer - virtual tour at the New Millennium Observatory, a seafloor observatory at an active underwater volcano %K #EducationalResources %K #SubjectResources %K activities %K classroom %K curricula %K earth science %K education %K groundwater %K K-12 %K lesson plans %K schools %K scientists %K seafloor %K standards %K teacher resources %K teaching %K underwater %K volcano %K water %K water cycle %G eng %U http://www.pmel.noaa.gov/vents/nemo/explorer.html %0 Generic %D 0 %T New England Geothermal Professional Association %K #Geothermal %K #GeothermalHomeownerResources %K ECS %K geothermal %K Ground Source Heat Pump %K GSHP %X NEGPA is a regional non-profit association advocating for the development of Geothermal Systems as a dependable, cost-effective, renewable resource for New England. Their website contains a host of resources for homeowners and professionals. %G eng %U http://www.negpa.org/ %0 Generic %D %T New England Intgercollegiate Geological Conference (NEIGC) %K #EducationalResources %K #Fieldtrips %K conference %K field trips %K geologic history %K New England %K site %X A low-cost autumn weekend of fieldtrips highlighting the geology of a different part of New England every year %G eng %U http://w3.salemstate.edu/ lhanson/NEIGC/index.html %0 Generic %D %T The New England Seismic Network %K #Earthquakes %K #EducationalResources %K #NaturalHazards %K earthquakes %K map %K seismicity %K shaking %K tremor %I Weston Observatory %G eng %U http://quake.bc.edu:8000/index.htm %0 Generic %D %T News and Current events in Earth Science on Geology.com %K #Blogs %K #EducationalResources %K events %K GEOLOGY %K news %I Geology.com %G eng %U http://geology.com/news/ %0 Generic %D 0 %T Northeast States Emergency Consortium %K coastal erosion %K earthquakes %K flooding %K landslides %K massachusetts %K natural hazards %G eng %U http://www.nesec.org/