Denali National Park and Preserve (DENA), located in central Alaska, is home to iconic and dynamic landscapes surrounding the tallest mountain range in North America, the Alaska Range. DENA preserves over 6 million acres of wild land that provides opportunities for recreation, subsistence hunting and gathering, preservation of cultural resources, and scientific research. Despite its size and popularity, DENA has only one road—the dead-end, 92-mile Denali National Park Road (hereafter referred to as the Park Road). The Park Road is mostly gravel; only the first 15 miles are paved. It is the only access for most DENA infrastructure, including visitor centers, staff facilities, campgrounds, and businesses. The Park Road crosses a steep, constantly changing landscape, shaped by actively deforming and uplifted bedrock, glacier and meltwater erosion, and various permafrost processes. Geologic hazards (geohazards) such as rockfall, debris flows, and landslides cause significant damage to the Park Road every year, requiring periodic closure, and costing millions of dollars in repair and maintenance. For the first time in the park’s history, the Park Road is closed near its midpoint for an entire season due to displacement caused by the Pretty Rocks rock glacier and landslide complex. In addition, DENA is situated along a major fault system and experiences numerous earthquakes every year. Most are too weak to be felt, but a 7.9 magnitude earthquake shook the region in 2002, and at least one major landslide, which formed Bergh Lake along the Park Road corridor, was caused by seismic shaking in 1953. In response to the threat posed by geohazards, the U.S. Geological Survey (USGS) and the National Park Service (NPS) have partnered to produce a new, high-resolution geologic map to help identify basin sediments and bedrock geology, active faults, unstable slopes, and hazardous geologic substrates along the Park Road corridor and other areas that contain administrative infrastructure. This new geologic map augments previous broad scale, bedrock-focused maps and uses detailed, updated imagery and elevation data to provide a digital framework for future research, hazard identification, and infrastructural development.

La Botica is positioned on a topographic bench sharply inset into the gentle eastern slope of the high San Juan Mountains and perched ~70-80 meters above La Jara Creek (fig. 1), a tributary to the Rio Grande. Quaternary surface processes have modified the Tertiary bedrock deposits that underlie La Botica to shape the physical environment. Bedrock deposits consist of Oligocene to Pliocene volcanic and sedimentary deposits related to the Rio Grande rift and the San Juan volcanic locus of the Southern Rocky Mountains volcanic field. Bedrock deposits are mildly deformed by normal faulting and eastward tilting related to the onset of extensional deformation in the Oligocene and formation of the San Luis Basin. Bedrock incision by La Jara Creek is connected with evolution of the Rio Grande, and precursors, since middle to late Pleistocene regional alpine glacial cycles over the last 500 k.y.