NATIONAL PARK SERVICE STRATOTYPE INVENTORY PROJECT: PRESERVING HISTORICALLY AND SCIENTIFICALLY IMPORTANT GEOHERITAGE RESOURCES (Invited Presentation)

The National Park Service (NPS) stratotype inventory is a stewardship endeavor to protect historically and scientifically important geologic exposures that occur within the National Park System. Stratotype locations are where formal rock units were originally named and described, and serve as comparative reference sites. Analogous to libraries of the natural world, stratotypes are teaching sites for future generations of earth scientists and record suites of diagnostic criteria used to recognize and interpret geologic units. Stratotypes are an essential component of our national geologic heritage and are a cornerstone of the scientific value used to define the societal significance of geoheritage sites. The goals of this project are to systematically catalog stratotypes that occur within NPS units and increase awareness of the historical and scientific merit of stratotypes.

Determination of whether a stratotype occurs within an NPS area begins with an evaluation of park-specific Geologic Resource Inventory (GRI) map data to compile a list of recognized geologic units. Each map unit is queried using the United States Geological Survey (USGS) geologic names lexicon (“Geolex”) for published stratotype locations, descriptions, and references. Stratotype information from Geolex is mapped using USGS online tools and Google Earth combined with digital GRI-compiled maps. This method accurately locates stratotypes while validating GRI map unit polygons for agreement with Geolex nomenclature. A detailed spreadsheet that contains pertinent information for each geologic unit and its stratotype attributes is populated for each national park unit.

Stratotype inventory assessments and initial internal reports have been completed for each of the 32 inventory and monitoring networks encompassing more than 275 park units. The NPS stratotype inventory has identified more than 690 stratotype occurrences across the National Park System and fills a void in geologic information not previously compiled by the NPS. Throughout Jack Epstein’s career, he was an important liaison to the NPS and is recognized here for his numerous stratotype designations at Delaware Water Gap National Recreation Area, Cedar Creek and Belle Grove National Historical Park, and the Appalachian National Scenic Trail.