U.S. Geological Survey Data Series 671
The map documents and shapefiles used to create the maps provided in this report can be found in the arc folder. This folder also contains a read-me file that describes the GIS project in detail. Map documents were created with ESRI ArcGIS version 9.3.1. The shapefiles provided may also be viewed using other versions of ArcView, ArcGIS, or ArcExplorer software available for download (http://www.esri.com/software/arcexplorer/).