GEOLOGIC FIELD MAPPING USING DIGITAL PEN TECHNOLOGY
The digital pen consists of a standard ink cartridge pen equipped with a laser scanner that reads a proprietary gridded watermark printed with the base map imagery on standard paper. The pen’s scanner reads the watermark as lines are drawn on the map. The watermark is georeferenced and any line that is drawn with the digital pen will also be georeferenced. This allows for the creation of linework that is accurately located and precisely shaped.
We have successfully implemented this methodology in the field with promising results. Base maps can range from previous geologic mapping to topographic maps or satellite imagery. The pen makes a physical line on the map and lines can be stored on the pen’s memory chip in any line style recognized by ArcMap. The desired line styles (fault, contact, etc.) are displayed in a map key, either on the same page as the base map or a separate sheet of paper. The linework is then downloadable into ArcMap through a USB dock that reads the pen’s memory chip. The linework is imported as the linestyle that was chosen in the field. The linework is automatically saved into a separate annotation layer that records all marks made with the pen on the base map, including marks when no linestyle was selected from the key. This layer is useful for making notes on the base map. Data can be downloaded each day, resulting in daily annotation layers that are saved with that day’s date. This is advantageous because each annotation layer can be traced back to an entry in a properly dated field book.
Mapping on georeferenced paper eliminates the need for a computer in the field and provides greater accuracy than the “point and click” digitizing method. The pen facilitates a seamless transition from field data to GIS linework. Moreover, mapping with a digital pen makes heads-up digitizing of field maps unnecessary therefore saving time in the post-mapping process.