UNEARTHING TRUTHS AND TRANSFORMING MAPS AT FLORISSANT FOSSIL BEDS NATIONAL MONUMENT

Florissant Fossil Beds National Monument, in Florissant, Colorado, boasts one of the world’s most abundant and diverse fossil deposits. Protecting over 1,700 fossilized species, the park requires a new, highly accurate geologic map to both safeguard and reveal invaluable paleontological and geological resources, as well as promote an appreciation for geoheritage.

Historically, analog mapping techniques led to inaccuracies in the park’s geologic maps. Our project embraces modern mapping technology, leveraging advanced data collection tools including the Eos Arrow Gold GNSS receiver, NPS NTRIP corrections, and Esri GIS software. By operating high accuracy GNSS equipment in the field, we’ve achieved an astounding enhancement in the geospatial accuracy of geology within the park. Outcrop locations in the park are beneficial for future paleontological excavation and monitoring, and improves visitor experience for those who utilize the Florissant Explorer - an app for navigation and interpretation.

During the project, we identified a new lithology and prompted a reassessment of prior nomenclature, highlighting the impact of remapping the park. Notably, we observed lobate andesitic breccias and sandy mudstone on undulatory hilltops, termed the “andesitic diamictite”, not mentioned in literature. Rather than continuous beds mapped by Emmett Evanoff in 1992, we mapped the irregular outcrops of andesite, highlighting differences in detail from the Evanoff product and our work. Evanoff dissected the Florissant Lake Beds unit, as described by Wobus, R, and Epis, R, in 1978, to the six units observed today. He revised Epis and Wobus’ denotation of the Echo Park Alluvium to describe a boulder alluvium, designating it an outcrop of the Tallahassee Creek Conglomerate. Intrusive igneous boulders, provisionally labeled "boulder alluvium," lack volcanic detritus, leaving uncertainty about their classification and are a source of continued research in the park.

Enhancing the park’s stratigraphic understanding and map resolution supports interpretation, infrastructure projects, and resource management. The project will ultimately aid in fulfilling the mission to preserve the geological and paleontological resources of the park while fostering geoheritage.