GEOLOGIC MAPS OF THE FRUITA AND GOLDEN THRONE QUADRANGLES, CAPITOL REEF NATIONAL PARK, UTAH: WITH PRELIMINARY ANALYSIS OF STRATH BOULDER TERRACES AND LANDSCAPE EVOLUTION

The Fruita and Golden Throne Quadrangles are located in Capitol Reef National Park, south-central Utah. These quadrangles are the most widely used by visitors to the Park. From strictly a geologic standpoint, these maps provide an understanding of the geomorphology and colorful vistas observed in the Park. It is for these reasons that Capitol Reef National Park was established in 1971. Relative to a societal value standpoint, these maps assist park management in understanding human impacts, developing future facilities, and educating the public. Specifically, at Capitol Reef National Park, our maps provide insights into geologic hazards and identify locations of specific bedrock formations and their associated alluvium that provide the proper conditions for the growth of endangered plant species.

Maps often raise more interesting geologic questions than they answer. For example, our mapping has identified more than 150 basaltic boulder terraces perched above and adjacent to perennial stream beds that cut across the Waterpocket Fold. These strath terrace deposits may hold keys to a greater understanding of the landscape evolution of the Western Escarpment of the Waterpocket Fold. Statistical and analytical techniques applied to these strath terraces focus on spatial relationships including elevation and terrace width. Long profile correlation of terrace deposits (representing individual erosional/depositional events) can be estimated by evaluating strath terrace dips relative to the present stream bed profiles. All these data are derived from accurate maps. Statistical correlation of elevations and widths between drainages can also be derived from detailed maps. These correlations can be used in combination with cross-sectional profiles between drainages to establish the importance of major erosional/depositional events. These events, possibly climate related, may have dramatically impacted the landscape of Capitol Reef National Park.