Seafloor gravity measurements were made at 281 bottom stations in San Francisco and San Pablo Bays, California, on a series of lines oriented approximately NNE.. Line spacing was approximately 2.8 km and stations along the lines mere spaced 0.5 to 1.5 km apart, between 0.5 and 1.5 km perpendicular to the axis. Sample Bouguer anomalies in the San Francisco Bay range from -15 to +15 mGals (?0.1 mgal), while anomalies in the San Pablo Bay are consistently negative, ranging from +4.0 to -40.0 mGal (?0.2 mGal).