Preface
ABSTRACT This paper does not have an abstract. The Northern California Geological Society held its first meeting in May 1944. Over the years, a monthly lecture series and occasional field trips evolved to serve as the main venues for the Society. At first, meetings of the Society were held in various locations across the San Francisco Bay area, but eventually settled in San Francisco because of its concentration of petroleum and mining companies. One of the first field trips organized by the Society was a two-day trip to Mount Diablo held on 12–13 May 1950. This event marked the beginning of a close connection between the Society and the mountain. The Society prospered over the next few decades, but as the petroleum and mining companies relocated away from San Francisco, the membership broadened and the meeting location was moved to the East Bay and near Mount Diablo. Seventy-five years after its founding, the Society proposed to celebrate this anniversary by assembling a volume of new research and field guides by the members...