Permian reef complex of the Guadalupe Mountains

Exposures of Permian strata within Guadalupe Mountains National Park represent one of Earth’s best exposed and most accessible ancient reef complexes. Using the Permian Reef Geology Trail (PRGT), thousands of visitors a year hike the ancient sea floor profile extending from a 700 m deep basin floor to the top of the shallow water shelf, crossing an extensive transect of the well-documented Capitan Reef. The exquisite depositional facies observed along the PRGT are a fundamental teaching tool for geoscientists, where the evolution of sedimentary facies can be linked directly to the dramatic bathymetric profile. Geologists since the classic work of Philip King (1948) and Norman Newell et al. (1953) have illustrated this world class exposure, and hundreds of students and researchers have undertaken the pilgrimage in their footsteps. In addition to the PRGT, the Western Escarpment of the Guadalupe Mountains, which is as tall as the Grand Canyon is deep, provides a unique stratigraphic profile where the entire vista of shallow water shelf strata can be observed to transition through the reef to the basin floor. No single exposure in the stratigraphic record of North America so well exposes this shelf to basin transition and all its associated complexities.