Selecting locations for future geophysical surveys in search of the Dog Valley fault using earthquake, LiDAR, and GPS data.
I used the seismo-lineament analysis method to define the area where the ground-surface trace of the Dog Valley fault (DVF) – responsible for the M6 Truckee earthquake of 1966 – might be located. The best-fit plane through the aftershock locations reported by Greensfelder (1968) and Ryall et al. (1968) fall within the composite seismo-lineament. A set of structural-geomorphic lineaments along two parallel trends were located on hillshade images from a LiDAR-based 1-m DEM. The more southerly trend passes under or immediately adjacent to Stampede Dam. Youthful geomorphic features along both trends support the interpretation of late Quaternary faulting. Both trends are plausible ground-surface traces for the DVF. I selected geophysical survey locations along each trend to investigate. Both trends intersect the Polaris fault near Prosser Creek Dam, so this active conjugate system threatens several local dams whose failure would be disastrous to downstream communities along the Truckee River.