Abstract
The U.S. Geological Survey (USGS) compiled and analyzed data for mapping groundwater total dissolved solids (TDS) at the San Ardo Oil Field in Monterey County, California. Data include groundwater TDS and bicarbonate concentration from oil well and groundwater well samples, formation resistivity from borehole geophysical logs, porosity from well logs and rock core samples, temperature from water samples and well logs, selected oil well injection volumes, and geological formation depths. The data reported here are used in an accompanying manuscript (Stephens and others, 2025) that describes methods and results of mapping groundwater TDS. The modeled values from the related manuscript are also provided. A portion of these data were found in archived scanned pages in raster format on the California Geologic Energy Management Division (CalGEM) website (CalGEM, 2022) and have been compiled into machine readable numerical format. Other data, such as the geological layers, were generated during this project by interpreting borehole geophysical data from CalGEM (2022). All the data analyzed are part of the California State Water Resources Control Board Oil and Gas Regional Monitoring Program and the USGS California Oil, Gas, and Groundwater (COGG) program.