UPDATING PRECISION OF FLORISSANT FOSSIL BEDS NATIONAL MONUMENT’S GEOLOGIC MAP USING HIGH ACCURACY GIS METHODS

Florissant Fossil Beds National Monument preserves hundreds of unique species of plants and insects from the late Eocene, as well as some of the largest petrified stumps in the world. A high-accuracy, comprehensive geologic map of the park is necessary for both protecting paleontological resources and interpretation. Precise data are used in National Environmental Policy Act (NEPA) evaluations when infrastructure projects and paleontological excavations are planned. The data are also used in documenting and monitoring resources, and with mobile and print maps available to visitors of the park to promote engagement and understanding.

Two previous geologic maps of the park were created using topographic maps and colored pencils, and features were located based on navigational skills for using these maps in field settings. Now, we are using high accuracy hardware and software products to improve the resolution and usability. We used an Eos Arrow 100 and Eos Arrow Gold GNSS receiver, NPS NTRIP corrections, and Esri’s suite of products including ArcGIS Pro, ArcGIS Online, and Field Maps to collect data with an accuracy of several centimeters. Issues of connectivity within the park limit accuracy in remote areas of the park to 30-60 centimeters.

Using the methods described, we have been able to improve the accuracy of the location of the geologic units by nearly 40 meters in portions of the monument. The improved accuracy and precision of the geologic map better supports the park’s mission to preserve and protect the paleontological and geological resources unique to the area.

This project is supported by National Park Service funding through the Natural Resource Preservation Program, which supports an eighteen-week internship sponsored by Intergovernmental Internship Cooperative in collaboration with Southern Utah University.