REAL-TIME DIGITAL MAPPING OF THE INDIAN PASS QUADRANGLE (1:24,000-SCALE), CODY, WYOMING WITH TABLET PCS: GEOLOGIC MAPPING FOR INFORMED COOPERATION BETWEEN CITY PLANNERS AND MINERAL INDUSTRIES

The Indian Pass Quadrangle (1:24,000-scale), located immediately south of Cody, Wyoming, provides a unique opportunity to map an area whose geologic information has immediate socioeconomic and scientific benefits. The Indian Pass Quadrangle is located in an area that is undergoing rapid residential and mineral resource land management changes. Private residences are spreading south from the town of Cody towards active gypsum quarries which are mining from the Middle Jurassic Gypsum Spring Formation. A detailed geologic map of the surficial geographic distribution of bedrock units in the Indian Pass Quadrangle aids land-use planners in Cody and the industrial mineral industry in locating additional gypsum deposits.

Recent advancements in computer performance, battery life, and design permit effective field application of pen-based tablet computers with desktop-equivalent performance. Tablet PC’s run full versions of GIS programs (eg. ESRI ArcGIS) that along with the advantages of pen-based computing can be used to ‘digitize’ formation contacts directly in the field. This allows for rapid production of digital maps that removes the post-collection digitization process. This eliminates a step in which error can enter the digital mapping process.

Mapping of the Indian Pass Quadrangle indicates that thick gypsum beds contained at the base of the Gypsum Spring Formation are restricted to the limbs of a series of anticlines and synclines that trend approximately N-S across the map area. However, thick gypsum units are not continuous and are apparently separated by paleohighs (of Triassic Chugwater Formation) that existed during the Middle Jurassic. Understanding the distribution of formations and recognizing paleostructures through geologic mapping allows for more informed decisions to be made by city planners and the mineral industries mining the gypsum units.