2014 SLOPE FAILURES IN THE NEW RIVER MOUNTAINS

August 19, 2014 yielded an extreme precipitation event that brought over 5 inches of rain in 12 hours to the New River Mountains area of central Arizona, triggering hundreds of slope failures, including numerous debris flows. Initiation points of these slope failures were mapped using Google Earth historical imagery. Slope failures were classified based on width of the scoured channel, presence of levee and snout boulder deposits, and evidence of movement of megaclasts. Initiation points were transferred to ArcMap and overlain on a DEM and slope map derived from USGS 10 meter elevation data in order to obtain slopes at the point of failure. Additionally, field studies in progress will quantify scoured channel dimensions and levee and snout boulder deposit volume for debris flows in the two main lithologies of the area.