Neogene Uplift and Basin Development Along The Denali Fault System in the Eastern Alaska Range, Alaska
Earth and Planetary Sciences, University of California-Davis, Davis, CA, USA
Uplift and exhumation in the Alaska Range are related to slip on the Denali Fault system. Rapid exhumation in the Mt. McKinley region of the central Alaska Range at ~5-6 Ma is thought to result from either collision of the Yakutat microplate with southern Alaska or a change in relative motion between the Pacific and North American plates. Documented Neogene exhumation in the eastern Alaska Range also suggests a change in relative motion across the Denali fault at ~5-6 Ma, yet cooling age data are sparse east of the Delta River and structural controls on Neogene exhumation in this area are largely unknown. I hypothesize that thrust faults play an essential role in accomplishing exhumation of rocks east of the Delta River and that local basin sediments record this exhumation. To test this, I will explore the tectonic history of the McCallum Creek area, south of the Denali fault and east of the Delta River by performing geologic mapping, fault slip analyses, thermochronometry, and detrital clast dating. By combining these data, I will construct a relationship between slip on active faults in the Denali fault system, exhumation and erosion of rocks in the eastern Alaska Range, and development of foreland basins. Characterizing the geometry and timing of exhumation in the McCallum Creek area will increase our understanding of why and how rapid exhumation in the Alaska Range initiated at ~5-6 Ma and the implications this exhumation has for basin development near the Alaska Range.
AAPG Search and Discovery Article #90199 © 2014 AAPG Foundation 2014 Grants-in-Aid Projects