FIGURE 4.3.-Geologic sketch map of the northern Coast Ranges, central California, showing faults with Quaternary activity and basin deposits in northern section of the San Andreas fault system. Fault patterns are generalized, and only major faults are shown. Several Quaternary basins are fault bounded and aligned parallel to strikeslip faults, a relation most apparent along the Hayward-Rodgers Creek-Maacama fault trend.