ANALYSIS OF SEISMIC ACTIVITY AND POTENTIAL SEISMIC HAZARDS OF THE FONTANA SEISMIC TREND IN SOUTHERN CALIFORNIA

Southern California is a seismically active region with a large population. The Study Area is the Fontana Seismic Trend, an area of intense earthquake activity in western San Bernardino County. There has not been much significant work done to quantify the potential seismic hazard posed by it. This presentation will show that there is potential for a moderate seismic event on the Fontana Seismic Trend that will likely cause quite a bit of damage and disrupt lives. The major faults nearby have been studied extensively, but this is not the case for the Fontana Seismic Trend. When plotted on a map, the earthquake epicenters of the Fontana Seismic Trend display a significant linear pattern both two dimensionally and three dimensionally. In this presentation, the location and direction of movement of the underlying fault are identified and configured to fit the earthquake data. Using the plotted fault location, direction of movement and length, the maximum potential event that might occur on this fault was also quantified. HAZUS-MH (a FEMA software extension to ArcGIS) was used to perform a seismic hazard analysis to find out what type of damage and casualties can be expected if a moderate event occurs on this fault. This presentation discusses the methods used to determine the fault parameters and details the results from the seismic hazard analysis.