This dataset accompanies geologic map publication " Geologic and geophysical maps of the onshore parts of the Santa Maria and Point Conception 30' x 60' quadrangles, California "; U.S. Geological Survey Scientific Investigations Map 3473. Data presented here include the digital geologic map database, paleontological sample locations and descriptions, and point data sets from magnetic and gravity data. The geologic database includes spatial feature classes and non-spatial tables that collectively contain the geologic information presented in the map plate. Fossil sample localities are included as a point feature class in the geologic map database and as two spreadsheet tables of fossil sample localities and fossil checklists. The location of gravity stations in the map area are compiled and augmented by new measurements of the Santa Maria and northern part of the Point Conception 30 x 60 quadrangle, California. This dataset represents an edited version of Langenheim (2013) U.S. Geological Survey Open-File Report 2013-1282 and includes data that were collected after that publication. Point data representing the isostatic gravity field, gridded at a 200-m spacing, are presented for two reduction densities: 2000 kg/m3 and 2670 kg/m3. Point data representing the magnetic field, gridded at a 200-m spacing, are presented for magnetic data that have been filtered to emphasize shallow-depth and medium-depth magnetic sources. Boundaries of density and magnetic sources were derived from application of the maximum horizontal gradient method for the Santa Maria and Point Conception 30 x 60 quadrangle, California. Point data representing the maximum horizontal gradient boundaries in the magnetic field are presented for the total magnetic field and for magnetic data that have been filtered to emphasize shallow-depth and medium-depth magnetic sources. Point data representing the maximum horizontal gradient boundaries in the gravity field are presented for two reduction densities: 2000 kg/m3 and 2670 kg/m3.