Geologic map and database of the Salem East and Turner 7.5 minute quadrangles, Marion County, Oregon: A digital database By Terry L. Tolan1 and Marvin H. Beeson2 Digital Database By Christopher B. DuRoss3 Open - File Report 00-351 1Geosciences Group, Westinghouse Hanford Company, P.O. Box 1970, Richland, Washington 99352 2Geology Department, Portland State University, P.O. Box 751, Portland, Oregon 97207 3U.S. Geological Survey, 345 Middlefield Rd. MS-975, Menlo Park, CA 94025 U.S. Department of the Interior Bruce Babbitt, Secretary U.S. Geological Survey Charles Groat, Director 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 imply endorsement by the U.S. Government. This database, identified as "Geologic map and database of the Salem East and Turner 7.5 minute quadrangles, Marion County, Oregon A Digital Database" has been approved for release and publication by the Director of the USGS. Although this database has been subjected to rigorous review and is substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. Furthermore, it is released on condition that neither the USGS nor the United States Government may be held liable for any damages resulting from its authorized or unauthorized use. To obtain this pamphlet, contact: USGS Information Services Box 25286 Denver Federal Center Denver, CO 80225 303-202-4700 303-202-4693 FAX 2000 U.S. Department of the Interior U.S. Geological Survey Introduction This Open-File report is a digital geologic map database. This pamphlet serves to introduce and describe the digital data. There is no paper map included in the Open-File report. The report does include, however, PostScript plot files containing images of two geologic map sheets with explanation, as well as the accompanying text describing the geology of the area. For those only interested in a paper plot of information contained in the database or in obtaining the PostScript plot files, please see the section entitled "For Those Who Don't Use Digital Geologic Map Databases" below. This digital map database, compiled from previously published and unpublished data, and new mapping by the authors, represents the general distribution of bedrock and surficial deposits of the Salem East and Turner 7.5 minute quadrangles. A previously published adjacent geologic map and database (OF99-141) by Tolan, Beeson, and Wheeler (1999) contains a text file (geol.pdf, geol.txt or geol.ps), which provides current information on the geologic structure and stratigraphy of the area covered. Open File Report 99-141 may be found on the web at: http://wrgis.wr.usgs.gov/open-file/of99-141 The database delineates map units that are identified by general age and lithology following the stratigraphic nomenclature of the U.S. Geological Survey. The scale of the source maps limits the spatial resolution (scale) of the database to 1:24,000 or smaller. The content and character of the database, as well as three methods of obtaining the database, are described below. For those who don't use digital geologic map databases For those interested in the geology of the northwestern Oregon region of the Salem East and Turner 7.5 minute quadrangles who do not use an ARC/INFO compatible Geographic Information System (GIS), we have provided two sets of plot files containing images of much of the information in the database. There is a set of images in PostScript format and another in Adobe Acrobat PDF format (see the sections "PostScript plot files" and "PDF plot files" below). Those interested who have computer capability can access the plot file packages in any of the three ways described below (see the section "Obtaining the digital database and plot file packages"). However, it should be noted the plot file packages do require gzip and tar utilities to access the plot files. Therefore additional software, available free on the Internet, may be required to use the plot files (see section "Tar files"). Those without computer capability can obtain plots of the map files through USGS plot-on-demand service for digital geologic maps (see section "Obtaining plots from USGS Open-File Services") or from an outside vendor (see section "Obtaining plots from an outside vendor"). Digital Open-File contents This Open-File report consists of three digital packages. The first is the PostScript Plotfile Package, which consists of PostScript plot files of a geologic map with explanation (Sheets 1-2), as well as a PostScript version of a geologic description pamphlet, figures, and tables. The second is the PDF Plotfile Package, and contains the same plotfiles as the first package, but in Portable Document Format (PDF). The third is the Digital Database - metadata Package, and contains the geologic map database itself, and the supporting data, including base maps, map explanation, geologic description, and references. PostScript plot file package This package contains the images described here in PostScript format (see below for more information on PostScript plot files): slm.ps A PostScript plottable file containing an image of the geologic map, base map, cross sections, correlation of map units, description of map units and references of the Salem East 7.5 minute quadrangle at a scale of 1:24,000 (Sheet 1). tnr.ps A PostScript plottable file containing an image of the geologic map, base map, cross sections, correlation of map units, description of map units and references of the Turner 7.5 minute quadrangle at a scale of 1:24,000 (Sheet 2). readme.ps A PostScript plottable file of this document PDF plotfile package This package contains the images described here in PDF format (see below for more information on PDF plot files): slm.pdf A PDF containing an image of the geologic map, base map, cross sections, correlation of map units, description of map units and references of the Salem East 7.5 minute quadrangle at a scale of 1:24,000 (Sheet 1). tnr.pdf A PDF containing an image of the geologic map, base map, cross sections, correlation of map units, description of map units and references of the Turner 7.5 minute quadrangle at a scale of 1:24,000 (Sheet 2). readme.pdf A PDF of this document Digital database - metadata package The database package includes geologic map database files for the Salem East and Turner 7.5 minute quadrangles. The digital maps, or coverages, along with their associated INFO directory have been converted to uncompressed ARC/INFO export files. ARC export files promote ease of data handling, and are usable by some Geographic Information Systems in addition to ARC/INFO (see below for a discussion of working with export files). Raster data are stored in ARC grid format rather than export format to reduce file size. The ARC export files and associated ARC/INFO coverages, grids, and directories, as well as the additional digital material included in the database, are described below: ARC/INFO Resultant export file Coverage Description of Coverage Salem East quadrangle slm_geo.e00 slm_geo Faults, depositional contacts, and rock units in the quadrangle slm_stx.e00 slm_stx Fold axis as arcs, cross section lines Turner quadrangle tnr_geo.e00 trn_geo Faults, depositional contacts, and rock units in the quadrangle tnr_stx.e00 tnr_stx Geologic attitudes as points include pttype, strike, dip fields, dip values as annotation, fold axis as arcs, cross section lines tnr_ann.e00 tnr_ann Unit label leaders ARC/INFO grids Description of Grid slm_grd Salem East color geology grid merged with grid of topographic base tnr_grd Turner color geology grid merged with grid of topographic base The database package also includes the following files: ASCII text files, including explanatory text, PostScript plot files, Encapsulated PostScript files from Adobe Illustrator 8 used as map collars and Figures ----- (EPS and JPEG) for the geologic report, ARC Macro Language files for plotting maps, custom ARC lineset and a ARC Macro Language file for conversion of ARC export files into ARC coverages: metadata.txt The metadata readme.txt This file readme.ps This file as PostScript plot file import.aml ASCII text file in ARC Macro Language to convert ARC export files to ARC coverages in ARC/INFO slm_sh1.eps Encapsulated PostScript Adobe Illustrator 8 file (map collar) for the Salem East 7.5 minute quadrangle (Sheet 1) tnr_sh2.eps Encapsulated PostScript Adobe Illustrator 8 file for Turner 7.5 minute quadrangle (Sheet 2) slm.gra ARC Graphics Metafile for Salem East 7.5 minute quadrangle (Sheet 1) tnr.gra ARC Graphics Metafile for Turner 7.5 minute quadrangle (Sheet 2) slm_plot.aml Plot AML generates uncompressed PostScript of Salem East 7.5 minute quadrangle at 600 dpi (Sheet 1) tnr_plot.aml Plot AML generates uncompressed PostScript of Turner 7.5 minute quadrangle at 600 dpi (Sheet 2) geol61.lin Custom ARC lineset johanna.txt Custom ARC textset uncom_r Parameter file in svscplot.aml to uncompress and rotate PostScript file 90 degrees uncom Parameter file in stnplot.aml to uncompress PostScript file fnt038 Arc/Info font used with markerset fnt039 Arc/Info font used with markerset slm.tab Arc/Info grid remap table for colors (Salem East quadrangle) tnr.tab Arc/Info grid remap table for colors (Turner quadrangle) info Arc/Info directory log Arc/Info log file alc1.shd Arc/Info shadeset (custom) geologyk.mrk Arc/Info markerset (custom) droid.lut Arc/Info marker look up table (internal) exported as droid.lut.e00 slmpoly.lut Arc/Info line look up table for polygons (internal) slmln.lut Arc/Info line look up table for lines and fold arcs (internal) slmlm.lut Arc/Info line look up table for fold and fault markers (internal) tnrpoly.lut Arc/Info line look up table for polygons (internal) tnrln.lut Arc/Info line look up table for lines and fold arcs(internal) tnrlm.lut Arc/Info line look up table for fold and fault markers (internal) The following supporting directory is not included in the database package, but is produced in the process of reconverting the export files into ARC coverages: info/ INFO directory containing files supporting the databases. Tar files The two data packages described above are stored in tar (UNIX tape archive) files. A tar utility is required to extract the database from the tar file. This utility is included in most UNIX systems, and can be obtained free of charge over the Internet from Internet Literacy's Common Internet File Formats Webpage (http://www.matisse.net/files/formats.html). Both tar files have been compressed, and may be uncompressed with gzip, which is available free of charge over the Internet via links from the USGS Public Domain Software page (http://edcwww.cr.usgs.gov/doc/edchome/ndcdb/public.html). When the tar file is uncompressed and the data is extracted from the tar file, a directory is produced that contains the data in the package as described above. The specifics of the tar files are listed below: Name of Size of Directory Data package compressed compressed produced when contained tar file tar file extracted from (uncompressed) tar file -------------------- ---------------------- --------------------- ------------------------------------------ of00351ps.tar.gz 18.4 MB (206.9 MB) ps/ PostScript Plotfile Package of00351pdf.tar.gz 5 MB (5 MB) pdf/ Portable Document Format Package of00351db.tar.gz 14.5 MB (148.3MB) db/ Digital Database Package PostScript plot files For those interested in the geology of the northwestern Oregon region of the Salem East and Turner 7.5 minute quadrangles who don't use an ARC/INFO compatible GIS system we have included a separate data package with three PostScript plot files. The first two each contain a color plot of the geologic map database at 1:24,000 scale (Sheet 1 and 2, slm.ps, tnr.ps). Because this release is primarily a digital database, the plot files (and plots derived therefrom) have not been edited to conform to U.S. Geological Survey standards. Small units have not been labeled with leaders and in some instances map features or annotation overlap. Sample plots by the authors have proven to be quite legible and useful, however. The PostScript image of the geologic maps are 35 by 32 inches (Sheets 1 and 2), so they require a large plotter to produce paper copies at the intended scale. The PostScript plot files for maps were produced by the PostScript command using the uncompressed option in ARC/INFO version 7.2.1 for Unix. Encapsulated PostScript files, as well as the map templates (salem_comb2_o.eps, turner_comb_o.eps) contain a color plot of the cross-sections, list of map units, description of map units, and references, in map collar, (it was used as Placed EPS in the PostScript file from ARC/INFO). The final ARC/INFO PostScript files (slm.ps and tnr.ps ) contain an Encapsulated PostScript file generated by Adobe Illustrator version 8 (salem_comb2_o.eps and turner_comb_o.eps ) and placed into the ARC/INFO graphic metafile by an ARC plotting AML. This EPS file includes the marginal graphics and explanation of the map. The Plot AML's (salem_plot.aml and turner_plot.aml) use the coverages and grids to produce a printable PostScript file of the Turner and Salem E. files. The import.aml imports all the export (.e00) files into ARC/INFO. PDF plot files We have also included a second digital package containing PDF versions of the PostScript map sheets described above. Adobe Acrobat PDF (Portable Document Format) files are similar to PostScript plot files in that they contain all the information needed to produce a paper copy of a map and they are platform independent. Their principal advantage is that they require less memory to store and are therefore quicker to download from the Internet. In addition, PDF files allow for printing of portions of a map image on a printer smaller than that required to print the entire map without the purchase of expensive additional software. All PDF files in this report have been created from PostScript plot files using Adobe Acrobat Distiller. In test plots we have found that paper maps created with PDF files contain almost all the detail of maps created with PostScript plot files. We would, however, recommend that those users with the capability to print the large PostScript plot files use them in preference to the PDF files. To use PDF files, the user must get and install a copy of Adobe Acrobat Reader. This software is available free from the Adobe website (http://www.adobe.com). Please follow the instructions given at the website to download and install this software. Once installed, the Acrobat Reader software contains an on-line manual and tutorial. There are two ways to use Acrobat Reader in conjunction with the Internet. One is to use the PDF reader plug-in with your Internet browser. This allows for interactive viewing of PDF file images within your browser. This is a very handy way to quickly look at PDF files without downloading them to your hard disk. The second way is to download the PDF file to your local hard disk, and then view the file with Acrobat Reader. We strongly recommend that large map images be handled by downloading to your hard disk, because viewing them within an Internet browser tends to be very slow. To print a smaller portion of a PDF map image using Acrobat Reader, it is necessary to cut out the portion desired using Acrobat Reader and the standard cut and paste tools for your platform, and then to paste the portion of the image into a file generated by another software program that can handle images. Most word processors (such as Microsoft Word) will suffice. The new file can then be printed. Image conversion in the cut and paste process, as well as changes in the scale of the map image, may result in loss of image quality. However, test plots have proven adequate. Digital database format The databases in this report were compiled in ARC/INFO, a commercial Geographic Information System (Environmental Systems Research Institute, Redlands, California) ), with version 3.0 of the menu interface ALACARTE (Fitzgibbon and Wentworth, 1991, Fitzgibbon, 1991, Wentworth and Fitzgibbon, 1991). The files are in either GRID (ARC/INFO raster data) format or COVERAGE (ARC/INFO vector data) format. Coverages are stored in uncompressed ARC export format (ARC/INFO version 7.2.1 for Unix). ARC/INFO export files (files with the .e00 extension) can be converted into ARC/INFO coverages in ARC/INFO (see below) and can be read by some other Geographic Information Systems, such as MapInfo via ArcLink and ESRI's ArcView (version 1.0 for Windows 3.1 to 3.11 is available for free from ESRI's web site: http://www.esri.com). The digital compilation was done in version 7.2.1 of ARC/INFO for Unix. Obtaining the Digital Database and Plotfile Packages The digital data can be obtained in any of three ways: a. From the Western Region Geologic Information Web Page. b. Anonymous ftp over the Internet c. Sending a cd with request To obtain tar files of database or plot file packages from the USGS web pages: The U.S. Geological Survey now supports a set of graphical pages on the World Wide Web. Digital publications (including this one) can be accessed via these pages. The location of the main Web page for the entire USGS is http://www.usgs.gov The Web server for digital publications from the Western Region is http://geopubs.wr.usgs.gov Go to http://geopubs.wr.usgs.gov/open-file/of00-351 to access this publication. Besides providing easy access to the entire digital database, the Western Region Web page also affords easy access to the PostScript plot files for those who do not use digital databases (see below). To obtain tar files of database or plot file packages by ftp: The files in these reports are stored on the U.S. Geological Survey Western Region FTP server. The Internet ftp address of this server is: ftp://geopubs.wr.usgs.gov The user should log in with the user name anonymous and then input their e-mail address as the password. This will give the user access to all the publications available via ftp from this server. The files in this report are stored in the subdirectory: pub/open-file/of00-351 To obtain tar files of database or plot file packages on tape: Database files, PostScript plot files, and related files can be obtained by sending a compact disk (CD) with request and return address to: NE Oregon, Salem East and Turner 7.5 minute Geologic Map Plotfiles c/o Database Coordinator U.S. Geological Survey 345 Middlefield Road, M/S 975 Menlo Park, CA 94025 Do not omit any part of this address! NOTE: Be sure to include with your request the exact names, as listed above, of the tar files you require. An Open- File Report number is not sufficient, unless you are requesting both the database package and plot file package for the report. The compressed tar file will be returned on the compact disk. Obtaining plots from a commercial vendor Those interested in the geologic maps of the the northwestern Oregon region of the Salem East and Turner 7.5 minute quadrangles, but who use neither a computer nor the Internet, can still obtain the information. We will provide the PostScript plot files on digital compact disk (details below) for use by commercial vendors who can make large-format plots. Send a blank compact disk (CD) with request and return address to: NE Oregon, Salem East and Turner 7.5 minute Geologic Map Plotfiles c/o Database Coordinator U.S. Geological Survey 345 Middlefield Road, M/S 975 Menlo Park, CA 94025 Do not omit any part of this address! The compressed tar file will be returned on the compact disk. Make sure your vendor is capable of reading compact disks and PostScript plot files. Important information regarding compact disk format is included in the sections "Database Release Format", "Tar Files", and "PostScript Plot Files" above, so be certain to provide a copy of this document to your vendor. Obtaining plots from USGS Open-File Services U.S. Geological Survey is providing a plot-on-demand service for map files, such as those described in this report, through Open-File Services. In order to obtain plots, contact Open-File Services at: USGS Information Services Box 25286 Denver Federal Center Denver, CO 80225-0046 (303) 202-4200 1-800-USA-MAPS FAX: (303) 202-4695 e-mail: infoservices@usgs.gov Be sure to include with your request the Open-File Report number and the exact names, as listed in the Database Contents section above, of the plot files you require. An Open-File Report number and its letter alone may not be sufficient, unless you are requesting plots of all the plot files for that report. Converting ARC export files ARC export files are converted to ARC coverages using the ARC command IMPORT with the option COVER. To ease conversion and maintain naming conventions, we have included an ASCII text file in ARC Macro Language that will convert all of the export files in the database into coverages and create the associated INFO directory. From the ARC command line type: Arc: &run import.aml ARC export files can also be read by some other Geographic Information Systems. Please consult your GIS documentation to see if you can use ARC export files and the procedure to import them. Digital compilation Several different coverages were generated during the construction of the two geologic quadrangle maps. The topgraphic base map separates remain as grids, and are merged at the last step with the colored geology polygrids. The raster geology grids were converted to vector coverages with ARC/INFO's gridline routine. Alacarte and some custom menus and amls were used to project, transform, edit, tag and build, lines, polygons, and points in each map. A digital layout or map collar was made with Adobe Illustrator. The plot amls run in ARC/INFO and call the coverages, grids, and EPS to make uncompressed PostScript files. All maps are in UTM projection, zone 10, units meters, 1:24,000 scale. The pamphlet that describes the geology is saved to EPS from Microsoft Word. Annotation Within the structural coverage is an annotation showing dip amount associated with each attitude. This annotation layer is called by the plot aml used by ARC/INFO, using a custom ARC textset, johanna.txt. The plot aml convert all coverages into a PostScript file. Map unit labels (not annotation) are used to label geology polygons. Smaller polygons, in which the label would not fit, can be identified on plots by the color of the polygon. Base maps The source of the base maps used is the U.S. Geological Survey, 1:24,000 scale topographic maps, which have 10- foot contour intervals (1979). Topographic base separates for the Salem East and Turner 7.5 minute quadrangles were scanned on an ANATEK rasterizing scanner at 600 dpi as 1-bit TIFF images. Scanned TIFF images of the bases were registered and rectified in ARC/INFO and then made into grids. The images were clipped using ARC/INFO grid to conform to the area of the geologic coverages and merged with the geology grid to give an apparent transparent color image of both combined. These base map-geology layers are digital images but no information other than location is attached to the lines. The base-geology maps are provided for reference only. Spatial resolution Uses of this digital geologic map should not violate the spatial resolution of the data. Although the digital form of the data removes the constraint imposed by the scale of a paper map, the detail and accuracy inherent in map scale are also present in the digital data. The fact that this database was edited at a scale of 1:24,000 means that higher resolution information is not present in the dataset. Plotting at scales larger than 1:24,000 will not yield greater real detail, although it may reveal fine-scale irregularities below the intended resolution of the database. Similarly, where this database is used in combination with other data of higher resolution, the resolution of the combined output will be limited by the lower resolution of these data. Database specifics The map databases consist of ARC coverages and supporting INFO files, which are stored in a UTM (Universal Transverse Mercator) projection (Table 1). Digital tics define a 7.5 minute grid of latitude and longitude in the coverages corresponding with quadrangle corners. Table 1 - Map Projection The maps are stored in UTM projection PROJECTION UTM UNITS METERS -on the ground ZONE 10 -UTM zone PARAMETERS END The content of the geologic database can be described in terms of the lines, points, and the areas that compose the map. Descriptions of the database fields use the terms explained in Table 2. Table 2 - Field Definition Terms ITEM NAME name of the database field (item) WIDTH maximum number of digits or characters stored OUTPUT output width TYPE B-binary integer, F-binary floating point number, I-ASCII integer, C-ASCII character string N. DEC. number of decimal places maintained for floating point numbers Lines The lines (arcs) are recorded as strings of vectors and are described in the arc attribute table (Table 3). They define the boundaries of the map units, faults, and the map boundaries. These distinctions, including the geologic identities of the unit boundaries, are recorded in the LTYPE field according to the line types listed in Table 4. Table 3 - Content of the Arc Attribute Tables ITEM NAME WIDTH OUTPUT TYPE N.DEC Description FNODE# 4 5 B starting node of arc (from node) TNODE# 4 5 B ending node of arc (to node) LPOLY# 4 5 B polygon to the left of the arc RPOLY# 4 5 B polygon to the right of the arc LENGTH 4 12 F 3 length of arc in meters # 4 5 B unique internal control number -ID 4 5 B unique identification number LTYPE 35 35 C line type (see Table 4) SEL 1 1 I user-defined field used to save a selected set SYMB 3 3 I user defined field used to save symbol assignments (such as color) Table 4 - Line Types Recorded in the LTYPE Field (listed by coverage name) slm_geo contact, inferred map boundary normal fault, concealed normal fault, concealed _m normal fault, concealed, queried normal fault, concealed, queried _m normal fault, inferred normal fault, inferred _m slm_stx cross section f.a., monocline, certain f.a., monocline, certain _m f.a., monocline, certain, plunge f.a., syncline, inferred f.a., syncline, inferred _m tnr_geo contact, inferred map boundary normal fault, certain normal fault, certain _m normal fault, concealed normal fault, concealed _m normal fault, inferred normal fault, inferred _m tnr_stx cross section f.a., monocline, certain f.a., monocline, certain _m f.a., monocline, certain, plunge map boundary tnr_ann leader Areas Map units (polygons) are described in the polygon attribute table (Table 5) The identities of the map units from compilation sources are recorded in the PTYPE field by map label (Table 6). Note that ARC/INFO coverages cannot contain both point and polygon information, so only coverages with polygon information will have a polygon attribute table, and these coverages will not have a point attribute table. More complete descriptions of the various rock units can be found in the geologic report that accompanies the Tolan, Beeson, and Wheeler (1999) dataset, geol.txt or geol.ps. Table 5 - Content of the Polygon Attribute Tables ITEM NAME WIDTH OUTPUT TYPE N.DEC Description AREA 4 12 F 3 area of polygon in square meters PERIMETER 4 12 F 3 length of perimeter in meters # 4 5 B unique internal control number -ID 4 5 B unique identification number PTYPE 35 35 C unit label SEL 1 1 I user defined field used to save a selected set SYMB 3 3 I user defined field used to save symbol assignments (such as color) Table 6 - Map Units (See geol.txt or geol.ps in Tolan, Beeson, and Wheeler (1999) for descriptions of units) slm_geo Qal Qoal Tfr Tfsh Tfsf Tgsb Tgww Tms trn_geo Qal Qt Qls Qoal QTfs Tfr Tfsh Tfsh? Tfsf Tfg Tgsb Tgww Tgo Tms Points Data gathered at a single locality (points) are described in the point attribute table (Table 7). The identities of the points from compilation sources are recorded in the PTTYPE field by map label (Table 8). Map units are described more fully in the text file geol.txt or geol.ps in Tolan, Beeson, and Wheeler (1999). Note that ARC/INFO coverages cannot contain both point and polygon information, so only coverages with point information will have a point attribute table, and these coverages will not have a polygon attribute table. Of these two maps, Turner has point attribute data, and Salem East does not.geo Table 7 – Content of the Point Attribute Table (slm_stx contains lines only) Geologic Attitudes ITEM NAME WIDTH OUTPUT TYPE N.DEC AREA 4 12 F 3 PERIMETER 4 12 F 3 TRN_STX# 4 5 B TRN_STX-ID 4 5 B PTTYPE 35 35 C DIP 3 3 I STRIKE 3 3 I SEL 1 1 I SYMB 3 3 I Acknowledgments We wish to thank Scott Graham for the digital review of this Open File Report 00-351. References Cited Fitzgibbon, T.T., 1991, ALACARTE installation and system manual (version 1.0): U.S. Geological Survey Open- File Report 91-587B. Fitzgibbon, T.T., and Wentworth, C.M., 1991, ALACARTE user interface - AML code and demonstration maps (version 1.0): U.S. Geological Survey Open-File Report 91-587A. Tolan, T.L., Beeson, M.H., and Wheeler, K.L., 1999, Geologic map of the Scotts Mills, Silverton, and Stayton Northeast 7.5' quadrangles, northwest Oregon: A digital database: U.S. Geological Survey Open-file Report 99-141, 11 p., scale 1:24000, http://wrgis.wr.usgs.gov/open-file/of99-141. Wentworth, C.M., and Fitzgibbon, T.T., 1991, ALACARTE user manual (version 1.0): U.S. Geological Survey Open-File Report 91-587C. 2