||This dataset includes raw and processed, high-resolution seismic-reflection data collected in 2011 to collect information on active offshore faults. The survey area is offshore southern California between Long Beach and San Diego. The data were collected aboard the U.S. Geological Survey R/V Parke Snavely. The seismic-reflection data were acquired using a SIG 2mille minisparker system. Subbottom acoustic penetration spanned tens to several hundreds of meters, variable by location and equipment type.