To all users: This digital product, Surficial Geologic Map of the Heath-Northfield-Southwick-Hampden 24-Quadrangle Area in the Connecticut Valley region, West-Central Massachusetts, consists of explanatory text (OFR2006-1260G_text.pdf), 24 1:24,000-scale geologic maps (pdf format, also referred to as the browse graphics), 4 ArcGIS (ESRI)-format shapefiles with metadata (in .xml, .htm, and .txt formats), and scanned, georeferenced topographic base maps. OFR2006-1260G_text.pdf - This is the explanatory pamphlet (map text), which should accompany all geologic maps and data layers in this report. The GIS folder contains three subdirectories: shapes, metadata, and 24k_basemaps, discussed below. The shapes folder contains the following ArcGIS data layers in shapefile format: 1) Till, which contains four types of polygons: thin till, thick till, bedrock outcrops, and areas of abundant outcrop/shallow bedrock. Thin-till and bedrock outcrops polygons are mutually exclusive, thick-till polygons overlie areas of thin till, and abundant outcrop/shallow bedrock polygons overlie areas of thin till and bedrock outcrops. 2) Stratified_deposits, which contains polygons representing coarse and fine glacial stratified deposits. 3) Early_postglacial, which contains polygons for alluvial-fan deposits, stream terrace deposits, inland dune deposits, and talus deposits. 4) Postglacial, which contains polygons for floodplain alluvium, swamp deposits, and artificial fill. Swamp polygons may overlie alluvium polygons; artificial fill polygons may overlie areas of swamp or floodplain alluvium. Each shapefile has the following file component extensions: .dbf, .lyr, .prj, .sbn, .shp, and .shx. Each shapefile contains FGDC-compliant metadata in .xml format (which can be read in various styles using Arc Catalog). Note that all shapefiles and data layers in this report are in Massachusetts State Plane Coordinates NAD 83 (meters). All shapefiles used to create the geologic maps (browse graphics) have associated layer (.lyr) files. If you wish to use these to re-create our color scheme you can do so by opening the surficial_geology.mxd (located in the shapes folder) with ArcMap; this map document uses relative path names, so as long as the directory structure for the data remains the same (\GIS\shapes\), the layers should load correctly. If you move the data, you can add these layer files in ArcMap, then 'right-click' on the layer file, choose properties, choose the tab for source, click the button for 'set data source'; choose the current location of the shapefile, then click 'add'. Note that the layers should be used in the following order from top to bottom: shallow_bedrock.lyr, postglacial.lyr, early_postglacial.lyr, stratified_deposits.lyr, and till_bedrock.lyr. The metadata folder contains text and html versions of FGDC-compliant metadata for each shapefile. The 24k_basemaps folder contains georeferenced tiff images for each quadrangle; these are the old-series (1958-1977 editions) topographic quadrangles (1:24,000 scale) which have the same contour base (10-ft contour interval) as the original geologic mapping. Each quadrangle has the following file component extensions: .aux, .tif, .tfw, and .tif.lyr. Paper quadrangle maps were scanned and georeferenced by the Office of the Massachusetts State Geologist for this project. These images carry no warranty or metadata; they may not be useful for any other project or purpose. Each of these images has an associated layer file which attempts to colormap the image so that the white background, the green of forest areas, and the pink of urban areas all become transparent. These topographic images are part of the surficial_geology.mxd; they are used as base maps and are placed on top of the geologic data layers. Surficial_geology.mxd uses relative path names, so as long as the directory structure for the images remains the same (\GIS\24k_basemaps\), they should load correctly. If you move the data, you can add these layer files in ArcMap, 'right-click' on the layer file, choose properties, choose the tab for source, click the button for 'set data source', choose the current location of the shapefile, then click 'add'. The 24K_GRAPHICS folder contains the browse graphics in .pdf format: Sheet#_Quadrangle_name.pdf - These maps show the postglacial deposits, early postglacial deposits, stratified deposits, till, and bedrock outcrops of the individual quadrangle on a scanned topographic base at 1:24,000 scale. These graphics are provided to demonstrate the geologic contacts at the appropriate data scale of 1:24,000, they do not contain explanatory text or unit descriptions. All of these maps can be printed on 20" x 30" paper (portrait orientation). All sheets should be accompanied by the explanatory pamphlet OFR2006-1260G_text.pdf. Users can create similar maps by opening the surficial_geology.mxd with ArcMap or by using the layer files in the shapes and 24k_basemaps folders. Note that the geology is mapped only within the Massachusetts portion of quadrangles which cross state boundaries. Contact information: If you have questions regarding the data provided in this report please contact: Janet Stone (jrstone@usgs.gov) or Mary DiGiacomo-Cohen (mdicohen@usgs.gov) (860) 291-6748 or (860) 291-6769, USGS, 101 Pitkin St., East Hartford, CT, 06108.