U.S. DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY Bedrock Geologic Map of Vermont [Scale 1:100,000] Scientific Investigations Map 3184 By Nicholas M. Ratcliffe (1) Rolfe S. Stanley (2)* Marjorie H. Gale (3) Peter J. Thompson (3) and Gregory J. Walsh (1) 2011 version 1.0 Prepared in cooperation with the Vermont Geological Survey ________________________________ (1) U.S. Geological Survey (USGS) Reston, VA 20192 Montpelier, VT 05601 (2) University of Vermont Burlington, VT 05401 *Deceased (3) Vermont Geological Survey (VGS) Waterbury, VT 05671 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Source of Geologic Data: Published and unpublished data. See the references on the printed paper map or Adobe Acrobat Portable Document Format (PDF) files. Additional contributions to the map were made by Norman L. Hatch, Jr., Douglas W. Rankin, Barry L. Doolan, Jonathan Kim, Charlotte J. Mehrtens, John N. Aleinikoff, and J. Gregory McHone. Digital cartography in Adobe Illustrator by Linda Masonic (USGS). Geographic Information System (GIS) database by Walsh and Gale. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ This report is available from: http://pubs.usgs.gov/sim/3184/ U.S. Geological Survey Information Services Box 25286, Denver Federal Center Denver, CO 80225 1-888-ASK-USGS http://ask.usgs.gov/ OR Vermont Geological Survey 103 South Main St., Logue Cottage Waterbury, VT 05671 802-654-8951 http://www.anr.state.vt.us/dec/geo/vgs.htm ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ The GIS database was compiled in ArcGIS version 10.0. The paper map and PDF files were compiled in Adobe Illustrator version CS4. Topographic base produced by scanning photo positive separates of the following 30x60 (1:100,000) USGS topographic maps: Albany, MA-NY-VT, 1989 Claremont, NH-VT, 1985 Glens Falls, NY-VT, 1989 Keene, MA-NH-VT, 1986 Rutland, NH-VT, 1985 Ticonderoga, NY-VT, 1989 Lake Champlain North, VT-NH, 1981 Lake Champlain South, VT-NY, 1981 Mount Mansfield, VT, 1986 Montpelier, VT, 1986 Groveton, NH-VT-ME, 1988 Mount Washington, NH-VT-ME, 1989 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Suggested Citation: Ratcliffe, N.M., Stanley, R.S., Gale., M.H., Thompson, P.J., and Walsh, G.J., 2011, Bedrock geologic map of Vermont: U.S. Geological Survey Scientific Investigations Map 3184, scale 1:100,000, 3 sheets. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ This Readme.txt file briefly describes the GIS data only. Users of the GIS database should also see the paper maps and/or PDF files to see the complete report. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Direct questions or comments on the geology or database to: Gregory Walsh (USGS): P.O. Box 628, Montpelier, VT 05601 e-mail: gwalsh@usgs.gov OR Marjorie Gale (VGS): 103 South Main St., Logue Cottage Waterbury, VT 05671 email: marjorie.gale@state.vt.us ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Description: The bedrock geology was mapped to study the geologic and tectonic history of the State of Vermont. The digital data are intended for use by all government, academic, commercial, or other agencies in need of digital geologic map information. The bedrock geology was last mapped at a statewide scale 50 years ago at a scale of 1:250,000 (Doll and others, 1961). The 1961 map was compiled from 1:62,500-scale or smaller maps. The current map was created to integrate more detailed (1:12,000- to 1:24,000-scale) modern mapping with the theory of plate tectonics to provide a framework for geologic, tectonic, economic, hydrogeologic, and environmental characterization of the bedrock of Vermont. Reference Cited: Doll, C.G., Cady, W.M., Thompson, J.B., Jr., and Billings, M.P., 1961, Centennial geologic map of Vermont: Vermont Geological Survey, scale 1:250,000. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Date of latest revision: February 22, 2012 This database was created in ArcGIS version 10.0 on an IBM-compatible personal computer running Windows 7. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ GIS data (shapefiles) are in Vermont State Plane coordinate system. Digital map units in meters. National Geodetic Horizontal Datum: North American Datum of 1983 (NAD 1983). COORDINATE SYSTEM DESCRIPTION Projection STATE PLANE Zone 5526 Datum NAD83 Units METERS Spheroid GRS1980 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Directory layout: http://pubs.usgs.gov/sim/3184/ --SIM3184_1.PDF---Sheet 1 Geologic map, South (54" tall x 77" wide) --SIM3184_2.PDF---Sheet 2 Geologic map, North (54" tall x 77" wide) --SIM3184_3_front_print.PDF---Front of Sheet 3 Description and Correlation of Map Units (77" wide x 54" tall) --SIM3184_3_front_search.PDF---Front of Sheet 3 Description and Correlation of Map Units (6 pages each 44" wide x 35" tall) --SIM3184_3_back.PDF---Back of Sheet 3 Index map and references (34" tall x 44" wide) Note on Sheet 3: Two PDF files are provided for the front of sheet 3, with two differently sized artboards due to a problem associated with the search and find features in Adobe Acrobat. In the full-size print file (77 x 54 artboard) the search and find features do not automatically pan to the proper location, making it difficult to find searched text. Search and find correctly pans in the search file with the smaller artboard (44 x 35 artboard), but the document is tiled into six separate pages. http://pubs.usgs.gov/sim/3184/Downloads -README.TXT---ASCII text description (this file) -METADATA.HTML---Metadata file in html format -METADATA.TXT---Metadata file in text format -METADATA.FAQ.HTML---Metadata frequently asked questions format -METADATA.XML---Metadata file in XML format -SIM3184.ZIP---Compressed database files with base -SIM3184nobase.ZIP---Compressed database files without base -SIM3184GE.ZIP---Compressed database files in Google Earth format Content of ZIP files: SIM3184.ZIP |--VTBedrockGeology01.mxd--ArcMap document file |--README.TXT |--METADATA.HTML |--METADATA.FAQ.HTML |--METADATA.XML |--METADATA.TXT | |---SHAPE--Folder contains ArcGIS shapefiles and attribute tables | |---SYMBOLS--Folder contains supporting layer files for symbology | in ArcGIS | |---GRAPHICS--Folder contains TIFF and JPEG image files | | Base maps (Georeferenced in ArcGIS): |--SIM3184_1_South.TIF---Cropped image graphic of southern map sheet 1 |--SIM3184_2_North.TIF---Cropped image graphic of northern map sheet 2 | SIM3184nobase.ZIP |- Same as SIM3184.ZIP but without the TIFF base maps SIM3184ge.ZIP | Simplified version of the GIS database in Google Earth format. | Does not include base or proper symbology and overprint patterns. | |--VTcontax_arc contacts and faults.kmz |--VTcontax_poly color definitions.kmz |--VTdikes_arc.kmz |--VTgeochronology_pts.kmz Files not in a Zip file: |JPEG files of the 3 map sheets are located in the GRAPHICS folder. | |---GRAPHICS--Folder contains TIFF and JPEG image files | Browse graphics (150 dpi, not georeferenced): |--SIM3184_1_South.JPG---Browse graphic of map sheet 1 (150 dpi) |--SIM3184_2_North.JPG---Browse graphic of map sheet 2 (150 dpi) |--SIM3184_3_front.JPG---Browse graphic of the front of map sheet 3 (150 dpi) |--SIM3184_3_back.JPG---Browse graphic of the back of map sheet 3 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Details of GIS database: BEDROCK GEOLOGY - In ESRI Shapefile format VTcontax_arc............. Lines for faults and contacts VTcontax_poly............ Polygons for geologic map units VTcontax_attrib.txt.......Attribute table for geologic map units (This file is joined in VTcontax_poly) VTdikes_arc...............Lines of dikes VTgeochrono_pts...........Points of of U-Pb zircon geochronology sample locations VTgeochrono_attrib.txt....Attribute table for geochronology points (text) (This file is joined in VTgeochrono_pts) BASE GIS DATA - In ESRI Shapefile format Files obtained from the Vermont Center for geographic Information at http://www.vcgi.org/ VTcountybnds_poly.........Polygons of county boundaries VTquad_poly...............Polygons of 7.5' quadrangle boundaries VTquad_tic................Points of corner tic marks of 7.5' quadrangles SYMBOLS - For ArcMap symbolization. Colors and symbols may differ slightly from the printed map and PDF files because cartography was done in Adobe Illustrator. VTcontax_arc contacts and fault symbols.lyr VTcontax_poly - color definitions.lyr VTcontax_poly - other patterns.lyr VTcontax_poly - sub_lith overprint patterns.lyr VTdikes_arc.lyr VTgeochronology point symbols.lyr The file "VTcontax_poly - other patterns.lyr" contains patterns that approximate the patterns shown on the printed map and PDF files. The patterns were drawn from the PATTERN field in the polygon feature class. In these instances, the underlying polygon has a unique color AND an overprint pattern to enable easier cartographic distinction. For example, LITH = 'Y1bm' is the Baileys Mills tonalitic gneiss, is shown with a green solid color fill and a red hash overprint pattern. The file "VTcontax_poly - sub_lith overprint patterns.lyr" contains patterns that are based on the SUB_LITH field in the polygon feature class. In these instances, the underlying polygons ARE NOT unique. Instead the overprint pattern indicates the presence of an additional rock type(s) or mineral in the underlying polygon. There are only three valid entries for SUB_LITH including: 'Scd', 'garnet overprint', and 'granite overprint'. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ The following is a description of the Shapefiles. _________________________________________________________________ CONTAX - CONTAX includes shapefiles of geologic map units, contacts, and faults. Polygons - CONTX VTcontax_poly LITH = The map unit designators, or map labels. "LITH" stands for lithology. CODE = Same as LITH, but used as the primary map label in New Hampshire, so it is included here. PATTERN = A text field describing cartographic overprint patterns unique to associated LITH values (see layer file description). The attribute table (VTcontax_attrib.txt) contains the following items: NOTE = Entry 'simplified description' indicates that the ROCKTYPES item is simplified from the text in the Description of Map Units. SUB_LITH = Text for overprint patterns that are not uniquely associated with CODE (see layer file description). C = Cyan color value for printing. M = Magenta color value for printing. Y = Yellow color value for printing. K = Black color value for printing. SORT = Sequential order of units listed in the Description of Map Units (DMU) on Sheet 3. SURF_BED = Surficial or bedrock unit. All entries are "bedrock". ROCKTYPE1 = Simplified primary lithology in the map unit. ROCKTYPE2 = Simplified secondary lithology in the map unit. ROCKTYPES = Description of unit. May be simplified to fit within 255 character limit. See Sheet 3 of the printed map for a complete description of the rocks. Descriptions in the GIS database were intentionally limited to 255 characters to maintain multi-platform readability. ZONE = geologic zone name SUITE = igneous suite name BELT = belt name GROUP = group name FORMATION = formation name MEMBER = member name ROCKCLASS = major rock classification type AGE = geologic age of the map unit _________________________________________________________________ Arcs - CONTAX VTcontax_arc Line data layer of geologic contacts TYPE1 - Type of geologic boundary Valid entries include: concealed contact contact dashed contact fault fault ? high angle fault (brittle fault) normal fault scratch boundary strike slip fault thrust fault open barb (1st generation, pre- or early metamorphic) thrust fault solid barb (2nd generation) _________________________________________________________________ Arcs - DIKES VTdikes_arc Arcs of dikes shown by short line segments on the geologic map. Items in the arc attribute tables include: LITH - Item "LITH" in VTDIKES_ARC contains the map unit designators. "LITH" stands for lithology and is equivalent to LITHCODE. Valid entries for LITH include: Dg - Granite and trondhjemite dikes of Chester and Athens dome and west of the Connecticut Valley Trough Jd - Dikes associated with the Monadnock Mountain stock Kmd - Dikes of the White Mountain Igneous Suite Kpd - Trachyte dikes of the Barber Mountain stock See Sheet 3 for a complete description of the dikes. _________________________________________________________________ Points - GEOCHRONOLOGY VTgeochrono_pts Points show locations of dated U-Pb zircon geochronology samples indicated on the geologic map and structure map on sheets 1 and 2. There are 51 sample locations. The locations were "heads-up" digitized in Arc/Info from the positions shown on the geologic map. SAMPLENO - Sample number shown on map LITH - Dated map unit SHEET - Location on north or south sheet INFO - Information about the dated rock RAD_AGE - Radiometric age with 1 sigma uncertainty in millions of years (Ma - mega annum) SHORT_REF - Abbreviated citation for source of age _________________________________________________________________ Note on tic marks: Corner tic marks from the statewide coverage of USGS 7.5-minute quadrangles. Tic marks are in Shapefile VTquad_tic. The corner tic marks are from VCGI (Vermont Center for Geographic Information): http://www.vcgi.org/ The North and South sheets were registered to four tic marks, shown schematically by item IDTIC number as follows: 320 1720 + + North Sheet + + 211 1111 310 1110 + + South Sheet + + 302 902 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ END