USGS-NPS JOINT EFFORT TO CREATE DIGITAL GEOLOGIC DATA FOR ALASKA NATIONAL PARKS

The U.S. Geological Survey (USGS) and National Park Service (NPS) are engaged in a joint effort to develop digital geologic datasets for Alaska National Parks. The USGS is developing a digital dataset of Alaskan geology for the next USGS national mineral resource assessment. This dataset includes a rich set of attributes to facilitate mineral assessment, while retaining use as a general research database. Concurrently, NPS developed a structure to meet the mandate of its Inventory and Monitoring Program for management and interpretive use. While contact between the agencies was maintained during these development processes, different agency cultures and goals led to different terminology and underlying philosophies to capture data. To minimize redundancy, NPS is working with USGS to convert USGS data to the NPS data structure for Alaska Parks.

Both datasets use ESRI software for spatial data, USGS largely using the coverage model and NPS employing the geodatabase model. Associated data is maintained in different database software in each agency. Each agency format has strengths and weaknesses; the goal is to minimize data loss between formats following conversion. The first conversion, for Aniakchak National Monument and Preserve (ANIA), had to resolve a variety of data incompatibilities. USGS surficial and bedrock geologic data is maintained in related databases; however, NPS topologic rules require contacts to be coincident in the surficial and bedrock “layers,” which was not the case for ANIA. The least confusing resolution of the problem was to create two independent datasets for ANIA. Additionally, all faults in USGS data are stored as contacts, whereas in the NPS data, while all faults and contacts are stored, faults cutting a single map unit are not considered contacts. These and other differences required a complex decision tree for data conversion. The NPS data structure was not designed to contain the complete USGS dataset; to minimize data loss, custom NPS “data layers” were designed, and additional tables were added to the NPS data structure.

The ANIA data has been successfully converted from the USGS structure and work is well along in conversion of the next park using lessons learned. In addition, we are preparing for anticipated issues that will arise in other parks due to differences in available data.