U.S. DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY Bedrock Geologic Map of the New Milford Quadrangle, Litchfield and Fairfield Counties, Connecticut [Scale 1:24,000] by Gregory J. Walsh (1) Open-File Report 03-487 2003 version 1.0 Prepared in cooperation with The State of Connecticut Geological and Natural History Survey This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards (or with the North American Stratigraphic Code). Any use of trade, product, or firm names is for descriptive purposes only and does not constitute endorsement by the USGS. Although this database has been used by the U.S. Geological Survey, no warranty, expressed or implied, is made by the USGS as to the accuracy and functioning of the database and related program material, nor shall the fact of distribution constitute any such warranty, and no responsibility is assumed by the USGS in connection therewith. ________________________________ (1) U.S. Geological Survey Montpelier, Vermont 05601 The text and maps in this report are part A, and the database is part B. Both parts are available at: http://pubs.usgs.gov/of/2003/of03-487 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Source of Geologic Data: Original data. Geology mapped by Walsh in 2000 and 2001. The bedrock geology was mapped using standard techniques. Location information was provided by a Rockwell PLGR+96 GPS receiver using the Federal precise positioning service. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ CD directory layout: |-README.TXT---ASCII text description (this file) | |---EXPORT---Contains Arc/Info GIS export-interchange files (e00) | |---SHAPE---Contains ArcView GIS shapefiles & lookup table for CONTX | polygon coverage | |---BASE---Contains basemap image file and worldfile | |---PHOTOS---Contains 118 photographs of the geology and landscape* | | | Compressed Encapsulated Postscript (EPS) versions of: | |--OF034871.ZIP---Plate 1 Geologic map (OF034871.EPS) | |--OF034872.ZIP---Plate 2 Fracture map (OF034872.EPS) |---WEB--------| Plate 1 = 34" tall x 44" wide | | Plate 2 = 34" tall x 44" wide | The files | | in this |--OF03487P.PDF---Text pamphlet in PDF; explanatory | folder are | text of the geology | available | (print version, 600 dpi) | online |--OF03487S.PDF---Text pamphlet in PDF | | (screen version 300 dpi) | |--OF034871.GIF---Browse graphic of Plate 1 | |--OF034872.GIF---Browse graphic of Plate 2 | |--OF034871.JPG---Image graphic of Plate 1 (200 dpi) | |--OF034872.JPG---Image graphic of Plate 2 (200 dpi) | |--METADATA.TXT---Metadata file in ASCII text format | |--METADATA.HTM---Metadata file in HTML format | |--METADATA_FAQ.HTM---Metadata file in Frequently | | Asked Questions format (HTML) | |--OF03487.ZIP---Compressed database files | | (without photos or base) | |--OF03487b.ZIP---Compressed database with base | | (without photos) | |--OF03487s.ZIP---Compressed database in STDS format | | (without photos) | |--SYMBOLS.ZIP---Compressed ArcPlot symbol files | |---SYMBOLS---Contains symbol and font files for ArcPlot * Note--Due to size constraints, the photos are only available on the CD, and cannot be downloaded on the internet. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Contents of of03487.zip: contx.dbf contx.e00 contx.shp contx.shx contx_li.dbf faults.dbf faults.e00 faults.shp faults.shx fnt025 fnt026 fnt035 fnt036 fnt038 fnt039 fnt040 geology1.mrk metadata.txt metadata.htm metadate_faq.htm outcrop.dbf outcrop.e00 outcrop.shp outcrop.shx photo.dbf photo.e00 photo.shp photo.shx strux.dbf strux.e00 strux.shp strux.shx readme.txt Contents of of03487b.zip: Includes all files in of03487.zip and the following files: NMbase.tif NMbase.tfw ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Most of this report is available from: http://pubs.usgs.gov/of/2003/of03-487/ A CD with all the digital data is available from: USGS Earth Science Information Center (ESIC) http://geography.usgs.gov/esic/esic_index.html or U.S. Geological Survey Information Services Box 25286 Federal Center Denver, CO 80225 1-888-ASK-USGS ask@usgs.gov Printed paper maps are available from: USGS Maps on Demand http://rmmcweb.cr.usgs.gov/public/mod/ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Description: The bedrock geology of the 7.5-minute New Milford, CT quadrangle consists of deformed Mesoproterozoic to early Paleozoic crystalline metamorphic and intrusive igneous rocks. The geology was mapped during 2000 & 2001 at a scale of 1:24,000. The bedrock geology was mapped using standard techniques. Location information was provided by a Rockwell PLGR+96 GPS receiver using the federal precise positioning service. The line and polygon data were compiled on a Mylar greenline of the 7.5-minute quadrangle and scanned at 400 dpi on an Anatech Eagle 4080T scanner. The raster files (TIF) were converted to vector files (DXF) using GTX OSR version 2.0 raster-to-vector conversion software. The vector files were imported to Arc/Info version 8.0.2. Point data were collected with GPS and a hand-held 3COM Palm Pilot III PDA computer. Data from the PDA were combined in Microsoft Access, and then imported as ASCII text files and DBASE IV (dbf) files into Arc/Info. The GPS data were collected in the UTM coordinate system in zone 18 datum NAD27. Raw GPS data were compared to the topographic base map of the area and repositioned to match the base. The original coordinates remain in the database. Preliminary Arc/Info coverages were registered to UTM coordinate system in zone 18 datum NAD27. All data were then projected to a geographic coordinate system in decimal degrees in datum NAD83. Direct questions or comments on this report to: Gregory J. Walsh U.S. Geological Survey P.O. Box 628 Montpelier, Vermont 05601 Tel: 802-828-4528 e-mail: gwalsh@usgs.gov ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Date of latest revision: February 25, 2003 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ The GIS data associated with this report are provided in two common GIS formats. The GIS data were created in ARC/INFO version 8.2 on an Dell PC running Windows 2000. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Note on Metadata: FGDC compliant metadata for the report exists in several file formats. These metadata files were created with the mp metadata tool available from: http://geology.usgs.gov/tools/metadata/ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Digital data are in unprojected geographic coordinates (NAD83). Digital map units are in decimal degrees. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Computer Files: Some files have been archived using WinZip. Useful URL: http://winzip.com ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ******************************************************************** The following is a brief description of the geologic data layers, tables, and non-standard attributes used in this report. ******************************************************************** CONTX - Polygon data layer of bedrock geologic map units CONTX.PAT items: CODE - Bedrock geologic map unit code MAP_UNIT - same as CODE The following table lists the valid fields for CODE (or MAP_UNIT) and how the units are shown on the State bedrock geologic map by Rodgers (1985): CODE Rodgers (1985) ____ ______________ CZd Cd CZdq Cd CZm Cm CZma Cma OCr Or OCra Or+Ora OCrfq OCr OCrg OCr OCrk OCr OCs OCs OCsq OCs Obd Ob Obg Ob Obgd Ob Obqd Ob Obqm Ob Ocg Og Og Og Op -- Oqv -- Ow Ow Owm Owm OYmig Yg Yag Yga Ybg Yg Ybgg Yg Ycs Yg Ygg Ygr Yhg Ygh Ymig Yg Rodgers, John (compiler), 1985, Bedrock geological map of Connecticut: Connecticut Natural Resources Atlas Series, Connecticut State Geological and Natural History Survey, scale 1:125,000. CONTX_LI.DBF - Lithology attribute table If you are using Arc/Info you can access the data in this table using either the JOINITEM or RELATE functions and the item MAP_UNIT. Similarly, if you are using ArcView, add the table CONTX_LI.DBF to the project and use either the JOIN or LINK function. CONTX_LI.DBF items: MAP_UNIT = map unit designator SURF_BED = surficial or bedrock unit LITHPRI = primary lithology in the map unit LITHSEC = secondary lithology in the map unit FORM = formation name MEMBER = member name ROCKCLASS = rock type AGE = geologic age of the map unit FOSSIL = Yes means the unit contains fossils outside the map area COLOR = color of unweathered rock MINPRI = most characteristic minerals FAULTS - Line data layer of geologic faults FAULTS.AAT items: TYPE - Type of fault Type Code Description old thrust old thrust fault, deformed thrust thrust fault OUTCROP - Unattributed polygon data layer of bedrock outcrops examined during mapping STRUX - Point data layer of ductile and brittle structural geology STRUX.PAT items: STATION - Number of field station POSFMT - Position format from PLGR+96 GPS unit ZONE - UTM zone from PLGR+96 GPS unit HDATUM - Horizontal datum from PLGR+96 GPS unit EAST - UTM Easting value from PLGR+96 GPS unit in meters NORTH - UTM Northing value from PLGR+96 GPS unit in meters Note -- EAST and NORTH values collected in datum NAD27 HRZERR - Horizontal error from PLGR+96 GPS unit in meters Note on HRZERR -- The database includes the horizontal accuracy of point features as measured and recorded by the PLGR+96 GPS unit. The stated accuracy of the PLGR+96 is +/- 52 feet (15.8 meters). If the value is 0, the point was located by dead-reckoning, not GPS. ELEV - Elevation from PLGR+96 GPS unit in feet If the value is 0, the point was located by dead-reckoning, not GPS. VDATUM - Vertical datum from PLGR+96 GPS unit If the value is blank, the point was located by dead-reckoning, not GPS. TYPE - Refers to the general type of geologic feature. Valid entries include 'planar', 'linear', or 'other' SUB_TYPE - Refers to the specific geologic structure STRIKE - Angle measured from North in right-hand rule, units in degrees. DIP - Dip value (planar data) or plunge value (linear data), units in degrees DIPDIR - Direction of dip (planar data) or trend (linear data), units in degrees PARTING - 'Y' indicates the planar feature exhibits parting or fracturing parallel to the surface measured. THRUGO - 'Y' indicates the measured brittle feature is throughgoing and passes through the entire outcrop. Valid for SUB_TYPE = 'joint', 'joint set', and 'fault' REL_AGE - Refers to the relative age of ductile fabrics. Valid entries include: Y = Mesoproterozoic (YS2) -1 = Relative age is older than dominant fabric, age unknown n = Relative age is the dominant fabric, age unknown 1 = S1 Ordovician 2 = S2 Ordovician to Devonian? 3 = S3 Devonian NOMSMT - Number of features with same orientation. Valid for SUB_TYPE = 'joint' and 'joint set'. LITH - Freeform text indicating the rock type in which the feature was measured. TOPOFEAT - Topographic feature parallel to a geologic structure. Valid entries include: 'cliff', 'stream', and 'valley'. SYMBOL - Refers to the symbol number from the GEOLOGY.MRK markerset; used for plotting in Arcplot. SYMBOL_ANG - Refers to a standard Cartesian angle measured from East; used for symbol rotation and plotting in Arcplot, units in degrees Note -- The following three diagrams show an explanation of the geometry of STRIKE, DIPDIR, and SYMBOL_ANG: For STRIKE and DIPDIR: 0 North = 0 | East = 90 270 -----|----- 90 South = 180 | West = 270 180 For SYMBOL_ANG: 90 North = 90 | East = 0 180 -----|----- 0 South = 270 | West = 180 270 SYMBOL_ANG is used for symbol rotation. In ARC/INFO calculate pseudo item $angle = symbol_ang Planar symbols with symbol_ang = 0 look like this: __________ \/ Linear symbols with symbol_ang = 0 look like this: -----> Note -- Comma-delimited valid entries for... TYPE,SUB_TYPE,REL_AGE,SYMBOL,DIP include: linear,chatter marks,,59, linear,fold axis,1,115,1-89 linear,fold axis,2,116,1-89 linear,fold axis,3,117,1-89 linear,fold axis,Y,625,1-89 linear,glacial grooves,,59, linear,intersection lineation,2,116,1-89 linear,intersection lineation,3,117,1-89 linear,intersection lineation,Y,625,1-89 linear,mineral lineation,1,124,1-89 linear,mineral lineation,2,123,1-89 linear,mineral lineation,n,123,1-89 linear,refolded fold axis,1,115,1-89 linear,refolded fold axis,Y,625,1-89 linear,rods,2,123,1-89 linear,rods,n,123,1-89 linear,slickensides,,120,1-89 linear,stretched pebbles,2,123,1-89 other,cave,,0, other,prospect,,77, other,quarry,,77, other,sample,,0, other,spring,,85, planar,axial surface,1,29,1-89 planar,axial surface,2,40,1-89 planar,axial surface,2,41,90 planar,axial surface,3,44,1-89 planar,axial surface,3,45,90 planar,bedding,,1,1-89 planar,bedding,,2,90 planar,cleavage,2,14,1-89 planar,cleavage,3,10,1-89 planar,deformed schistosity,1,24,1-89 planar,dike,,344,1-89 planar,dike,,644,1-89 planar,fault,,125,1-89 planar,fault,,126,90 planar,gneissosity,2,14,1-89 planar,gneissosity,Y,110,1-89 planar,gneissosity,Y,111,90 planar,gneissosity,n,110,1-89 planar,gneissosity,n,111,90 planar,igneous flow foliation,,80,1-89 planar,igneous flow foliation,-1,80,1-89 planar,igneous flow foliation,n,80,1-89 planar,joint,,26,1-89 planar,joint,,27,90 planar,joint set,,490,1-89 planar,joint set,,491,90 planar,layer parallel schistosity,1,32,1-89 planar,layer parallel schistosity,1,33,90 planar,layer parallel schistosity,n,32,1-89 planar,refolded axial surface,1,29,90 planar,refolded axial surface,Y,626,90 planar,schistosity,1,32,1-89 planar,schistosity,1,33,90 planar,schistosity,2,14,1-89 planar,schistosity,2,15,90 planar,schistosity,n,20,1-89 planar,schistosity,n,21,90 planar,vein,,90,1-89 planar,vein,,91,90 ROTATION - Rotation sense of minor folds as viewed down plunge. Valid entries: 'cc' = counterclockwise and 'cw' = clockwise. SPACING - Spacing of joints in joint sets, units in meters WIDTH - Width or thickness of dike or vein, units in meters NETSLIP - Net slip of minor faults, units in meters TERMINATIO - Termination of joints. Valid entries include 'blind', 'abutting', and 'crossing'. MIN1 - Primary mineral MIN2 - Secondary mineral MIN3 - Tertiary mineral Note on MIN1, MIN2, and MIN3 -- The aforementioned items are used to describe minerals in veins. The following values from Kretz (1983) are used in the report: bt biotite qtz quartz Kretz, R., 1983, Symbols for rock-forming minerals: American Mineralogist, v. 68, nos. 1-2, p. 277-279. SAMPLE - Freeform text with sample information FAULTMOV - Relative motion sense for SUB_TYPE = 'fault'. Valid entries: 'normal', 'left lateral', and 'reverse' MAP_UNIT - Relate item for CONTX polygon coverage generated with Arc: IDENTITY command ORIGIN - Genetic origin of feature. Valid entries include: ign-met-sed = igneous, metamorphic, or sedimentary feature brittle = brittle deformation feature glacial = glacial feature other = other feature such as photo PHOTO - Point data layer of photographs; includes landscape and outcrop photos PHOTO.PAT items: STATION - Number of field station EAST - UTM Easting value from PLGR+96 GPS unit in meters NORTH - UTM Northing value from PLGR+96 GPS unit in meters Note -- EAST and NORTH values collected in datum NAD27 CODE - Relate item for CONTX polygon coverage generated with Arc: IDENTITY command (same as MAP_UNIT) TYPE - Valid entries include 'other' SUB_TYPE - Refers to the specific geologic feature, in this case 'photo'. PHOTO_FILE - Filename of TIFF format color photograph DESCRIPTIO - Description of feature(s) in photograph Note - The PHOTO coverage (or shapefile) is desgined for use with the ArcView hotlink tool or the ArcMap hyperlink tool. There are 118 digital photos located in the PHOTOS directory on the CD version of this report. Users should copy the photos to the same directory as the coverage (or shapefile). Users can also leave them in the current driectory and specify the path. ************************************************************************ The following is a description of the base used in this report: The basemap consists of: - TIFF format bitmap and worldfile (NMbase.tif & NMbase.tfw) - Surface water polygons (on paper maps and graphic files only) - Bedrock wells (on paper maps and graphic files only) TIFF format bitmap: Scanned black and white bitmap image in uncompressed TIFF format. Scanned at 400 dpi from a film positive of the USGS 7.5-minute New Milford, CT topographic map (1955, photorevised 1984). The TIFF image was registered with the Arc: REGISTER command. The world file (NMbase.tfw) contains the projection information. Surface water polygons: Lakes, rivers and ponds shown on the paper maps and graphic files were obtained from the Connecticut Map And Geographic Information Center (http://magic.lib.uconn.edu). The hydrography is not re-distributed in this report. Bedrock wells: Wells shown on Plate 1 of this report are from an unpublished preliminary dataset. The wells were inventoried by the USGS East Hartford, CT office from Well Completion Reports from well drillers. Contact Janet R. Stone for more information: Janet R. Stone U.S. Geological Survey UCONN-Avery Point 1080 Shennecossett Road Groton, CT 06340 860-405-9288 tel 860-405-9288 fax jrstone@usgs.gov *********************************************************************** Supporting files *********************************************************************** SYMBOLSETS AND FONT FILES: MARKERSET file (copy to any directory, specify a path when using) geology1.mrk FONT FILES (copy to the same workspace as the coverages) fnt025 fnt026 fnt035 fnt036 fnt038 fnt039 fnt040 The symbolset and font files are modified from the original versions of Fitzgibbon and Wentworth (1991): Fitzgibbon, T.T., and Wentworth, C.M., 1991, ALACARTE User Interface: AML code and demonstration maps, USGS Open-File Report 91-587. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ END