1. Map of California showing distribution of selenium concentrations in wells sampled by the Geological Survey, 1975-85 [cartographic material] Yale Public content 1986. 2002-06-01T04:00:00Z. 2023-10-19T03:01:33Z. Geological Survey (U.S.). The Survey ; Open-File Services Section, Western Distribution Branch. English. cartographic image. Public. California.