Digitization of Geologic Maps Using ArcINFO Software: A Method for Improving Access to Maps and Customizing Base Maps for Use in the Field

Digitization of paper maps using ArcINFO software provides a method for preserving the original material while making base maps for use in the field readily available and easy to modify to fit the users' specific needs. Original paper maps are digitized using a scanner. ArcINFO software is then used to rectify and replicate the original map features using vector shapefiles. The symbology of the original map may be maintained or modified at the user's discretion. When working from scanned maps, data is replicated at a higher scale than that of the original map to minimize errors due to pixelation of the scanned image. This data may then be converted into readily accessible formats for wider distribution than the original maps. External digital data, such as roads, hydrology, aerial photographs, and elevation models may be incorporated to provide added information. Field base maps may then be created and customized using the digitized geologic map and additional data. Field data may then be collected using a GPS unit or drawn onto these base maps, which can then be digitized and rectified to the original digital data. Geologic maps are fundamental tools in structural investigations. ArcINFO software allows for new data to be added to previously digitized geologic maps rapidly. Furthermore, ArcINFO software provides a system for data management and easy modification of data to produce customized finished maps.