readme.txt file for the Washington DC Area Geologic Map Database Version 1.0 - U.S. Geological Survey Open File Report, OFR-01-227 GENERAL DESCRIPTION: The Washington DC Area geologic map database (DCDB) is a combination of Geographic Information System (GIS) layers and Microsoft (MS) Access databases. The GIS Layers are: bedrock geology polygon, surficial geology polygon, linear feature data such as faults and fold axes, structural measurements, and sinkhole locations. There are two Microsoft Access databases, each of which contain attribute information that can be used as supplements to the GIS layers. One of these databases is the result of a database design process conducted by the Eastern Region Earth Surface Processes Team (EESP) of the U.S. Geological Survey. The other is the result of converting the EESP database to a format compatible with the North American Data Model Standard for Geologic Map Data Version 4.3 (NADM) of Johnson and others (1998). CD DIRECTORY LAYOUT: |--README.TXT__(This file) | | |--OF01227.APR__ArcView project for viewing data | | |--OF01227.PDF___Text pamphlet in Adobe Portable Document Format | | | |--ACCESS--(Contains two Microsoft Access databases and their ASCII text file equivalents) | | | | | |--COVERS--(Contains Arc/Info coverages for the geologic and base map themes) | | |--DATA---------| | | | |--EXPORT--(Contains Arc/Info export-interchange files for the geologic and base map themes) | | | | | |--SDTS----(Contains Spatial Data Transfer Standard (SDTS) data exchange files for the geologic and base map themes) | | | | | |--SHAPE---(Contains ArcView shapefiles for the geologic and base map themes) | | | |--OF01227P1.EPS | |--OF01227P1.PDF__(PostScript and Portable Document Format versions of the geologic units, faults and folds map | (Plate 1 of 2, 50" tall x 35" wide) |--GRAPHICS-----| | |--OF01227P2.EPS | |--OF01227P2.PDF__(PostScript and Portable Document Format versions of the geologic structure map (Plate 2 of 2, 50" tall x 35" wide) | | |--METADATA-----(Contains metadata files for the report) INSTRUCTIONS FOR INSTALLING THE DCDB ON A PERSONAL COMPUTER: Copy the directories from the CD-ROM (or internet) onto the hard drive of a personal computer that is running Microsoft Windows 95, 98, or NT, is running Microsoft Access 2000 (Access 97 won't work), and is running Arcview 3.1 or 3.2a. Arcview 3.0a is able to read the shapefiles, but the ArcView project that is provided on the CD-ROM may not work properly. Take care to preserve the directory hierarchy that is present on the CD-ROM. The ArcView project "of01227.apr" will work best if copied to the "c:\" drive in a directory named "ofr01227". If the file is placed on a drive with a different letter designation (i.e., "d:\" or "e:\"), ArcView will ask for the location of the .dbf and .shp files as it attempts to open project "of01227.apr". Alternatively, a text editor can be used to replace the path references in "of01227.apr". In order to be able to edit the data, highlight the files to which edits and updates would be made and right-click using the computer mouse. Select properties from the resulting menu. Then, remove the checkmark from the "Read Only" checkbox of the resulting dialogue box. OTHER SOFTWARE OPTIONS: In addition to a ArcView and MS Access combination, the DCDB data can be read by several other software packages. The ArcView shape files can be viewed with a free software package called "ArcExplorer", which is available at the Environmental Systems Research Institute (ESRI) web site: . The Arc/Info export files can be imported and viewed with Arc/Info version 7.1.2 and higher running on UNIX platforms as well as on Windows NT platforms. The text file versions of the MS Access tables can be imported into a wide variety of software including: Arc/Info, ArcView, MS Excel, and most text editors. USING MS ACCESS DATABASES WITH ARCVIEW: For ArcView 3.1 or 3.2a 1. Open ArcView 2. Continue with the default new project or use the project provided in this open file report by selecting "Open Project" from the "File" menu and navigating to "c:\ofr01227\of01227.apr". If you elected to stay with the new project, then you will need to start a new "View" by clicking on the "Views" tab of the "Project" window, and then clicking on the "New" button. If using a new project you will have to select "Add Theme" from the "View" menu and select the shapefiles that you desire. If you elected to use the project provided ("of01227.apr"), four views have already been created. These views are named Bedrock, Surficial, Fault, and Structure. 3. Select the "Extensions" option from the "File" menu and make sure that the "Database Access" option is checked. 4. Bring the project window to the front. To do this, select the project (e.g.,"of01227.apr" or "untitled") from the "Window" menu to make sure that the project window is active. 5. Select "SQL connect" from the "Project" menu. A dialog box will appear. 6. Select "MS Access Database" from the top pick list, and click the "Connect" button. 7. Then choose dcdb_eesp.mdb or dcdb_dm.mdb from the directory/file dialog box. 8. Double click on the table/query that you want. For example, select query [output5]. By double-clicking, its name will be placed in the "From" text box. 9. Double click on the fields that you want. For example, select "All Columns" and an "*" is placed into the "Select" box. Please see the ArcView Help Menu if more discussion about the "SQL Connect" feature is needed. 10. Once "Query" is clicked another table will appear in your ArcView project - by default it will be called [Table1]. Move the SQL dialogue box to the back or close it. 11. Select a field in this table and a field in an ArcView attribute table (i.e., the table that corresponds to the active theme in a "view") that you wish to join it to. For example, select the field in "Table1" (the ArcView name for "output5") by clicking on the top of the data column, then select the field in the attribute table of the "bedrock.shp" theme. 12. Make sure that the ArcView attribute table is active (click on its window) and then click on the join button or select join from the "table" menu. Useful joins include: MS Access ArcView -- output5 ----> bedrock.shp or surficial.shp -- CHARACTER --> bedrock.shp -- MAP_UNIT ---> bedrock.shp or surficial.shp -- clast_comb -> bedrock.shp or surficial.shp -- GEOCHRON ---> bedrock.shp -- FORMATION --> bedrock.shp or surficial.shp 13. Now the symbolization of the bedrock theme can be altered. For example, with "View1" active, double-click on the "bedrock.shp" theme in the legend bar to the left of the map. From the dialogue box that appears, select "Unique Value" from the "Legend Type" box and choose the field from the "Values Field" box. Then select "Apply", and a newly classified map is drawn. MAP INFORMATION: Projection and Coordinate System used: Geographic (latitude/longitude) Datum used: North American Datum of 1983 (NAD83) Ellipsoid used: GRS80 Map Units: Meters for Arc/Info coverages. Decimal degrees Scale of Compilation of Geologic Data: 1:100000 Scale of field mapping: 1:24000 to 1:100000 Basemaps: U.S. Geological Survey 1:100000-scale topographic map series, 30 X 60 minute sheets: Frederick, Washington West, Fredericksburg INTENDED USE: The DCDB Version 1.0 is a living and breathing database, in the sense that it can be expanded to include new types of data. The data entry forms can be used to input data associated with point locations, such as: geochemical analyses, isotopic ages, and outcrop lithologic descriptions. The database efficiency, data accuracy, and data retrieval aspects of the DCDB can be improved in subsequent versions. Greater reliance on reference tables is one way to improve data storage efficiency. Data accuracy questions or concerns should be directed to the Eastern Region Earth Surface Processes Team of the U.S. Geological Survey. These data were prepared by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, make any warranty, expressed or implied, or assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product or process disclosed in this report, and represents that its use would not infringe privately owned rights. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of this data or related materials. Reference therein to any specific commercial product, process, or related service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. REFERENCE Johnson, B.R., Brodaric, B., Raines, G.L., Hastings, J.T., and Wahl, R., 1998, Digital Geologic Map Data Model Addendum to Chapter 2 - Version 4.3: