Preliminary geologic map of Solano County and parts of Napa, Contra Costa, Marin, and Yolo counties, California
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Miscellaneous Field Studies Map↗
Geology topics
E. J. Helley
Publications and source records attributed to E. J. Helley.
Geologic map of Late Cenozoic deposits, Alameda County, California
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Miscellaneous Field Studies Map↗