Regions with cataloged oil well samples in the UCMP collections.

  STATE  COUNTY OR REGION
California Alameda County
California Butte County
California Colusa County
California Contra Costa County
California Fresno County
California Glenn County
California Humboldt County
California Imperial County
California Kern County
California Kings County
California Los Angeles
California Los Angeles Offshore
California Madera County
California Marin County
California Marin Offshore
California Mendocino County
California Merced County
California Modoc County
California Montery County
California Napa County
California Orange County
California Orange Offshore
California Placer County
California Riverside County
California Sacramento
California San Benito County
California San Bernardino County
California San Diego County
California San Joaquin County
California San Luis Obispo County
California San Mateo County
California Santa Barbara County
California Santa Barbara Offshore
California Santa Clara County
California Santa Cruz County
California Santa Cruz Island
California Santa Cruz Island Area
California Santa Rosa Island Offshore
California Solano County
California Solano Offshore
California Stanislaus County
California Sutter County
California Tehama County
California Tulare County
California Ventura County
California Ventura Offshore
California Yolo County
California Yuba County
Oregon Columbia County
Oregon Coos County
Oregon Douglas County
Oregon Jefferson County
Oregon Multnomah County
Washington Clallam County
Washington Cowlitz County
Washington Grays Harbor County
Washington Jefferson County
Washington King County
Washington Lewis County
Washington Pacific County
Washington Wahkiakum County
Wyoming Sublette County
Wyoming Teton County