TY  - RPRT
TI  - Preliminary Quaternary geologic maps of Santa Clara Valley, Santa Clara, Alameda, and San Mateo counties, California: A digital database
AU  - Edward J. Helley
AU  - R. W. Graymer
AU  - G. A. Phelps
AU  - P. K. Showalter
AU  - C. M. Wentworth
PY  - 1994
DO  - 10.3133/ofr94231
UR  - https://pubs.usgs.gov/publication/ofr94231
ID  - ofr94231
ER  -