Cosmogenic Nuclides Applied to Fault-Scarp Dating

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9980535PhillipsTiming of geologically recent faults is crucial to many neotectonic and environmental projects, but is difficult to determine if the fault movements occurred prior to recorded history. Faults that break the surface commonly leave a scarp due to differential vertical movements. Crudely, young fault scarps are steep and have sharp edges, whereas older ones have been eroded so that they are less steep and smoothed. Attempts to use this relationship more quantitatively estimate a scarp "diffusivity" to calibrate the age vs. fault scarp geomorphology relationship. However, this and other techniques have large errors which negatively impacts the ages of fault movement obtained. This project will attempt to use cosmogenic chlorine-36 accumulation around several faults of known age to refine estimation of fault scarp diffusivity. Results should help reduce errors in using fault scarp morphology and lower the costs of accurately estimating the age of fault movements.