This digital dataset is comprised of two separate data files that contain total dissolved solids, well construction, and well identifying information for 1,131 petroleum wells used to map salinity in and around 31 southern and central California oil fields. Salinity mapping was done for 27 fields located in the southern San Joaquin Valley of Kern County (North Belridge, South Belridge, Canfield Ranch, North Coles Levee, South Coles Levee, Cymric, Edison, Elk Hills, Fruitvale, Greeley, Jasmin, Kern Bluff, Kern Front, Kern River, Lost Hills, Mount Poso, Mountain View, Poso Creek, Rio Bravo, Rosedale, Rosedale Ranch, Round Mountain, San Emidio Nose, Tejon, Ten Section, Wheeler Ridge, and Yowlumne), 3 fields in the Los Angeles (LA) Basin [...]