Santa Rosa area showing active faults

Shaded relief image of the Santa Rosa area showing active faults (black lines) and the detailed rupture pattern of the Rodgers Creek Fault where it crosses central Santa Rosa (in red). The orange, bean-shaped area represents the dense, magnetic body of rock on the east side of the fault beneath Santa Rosa. This body of rock may be largely responsible for the pattern of surface faulting and may influence the distribution of small earthquakes (white and blue circles, blue for 1969 aftershocks) and the occurrence of the damaging 1969 earthquakes (approximately located by blue stars).