NEW GEOLOGIC MAP OF THE POINT SUR 30’X60’ QUADRANGLE, A TRIBUTE TO LEW ROSENBERG

This year, the California Geological Survey will release an updated geologic map of the Point Sur 30′ x 60′ quadrangle. Like previous maps in the CGS Regional Geologic Map series, the map will be on a 1/100,000-scale base map, but preserve as much detail as possible from original mapping at larger scale. The area of this map extends about 80 km east-west from the coast at Point Sur to the Bitterwater Valley along the San Andreas Fault Zone. It extends about 55 km north-south from Carmel Highlands to Lucia along the coast, and from Soledad to San Ardo in the Salinas Valley. The Point Sur 30’ x 60’ quadrangle includes much of the rugged Big Sur coastline, National Forest and wilderness in the Santa Lucia Mountains, and some of the richest farmland in the world in the Salinas Valley. The quadrangle lies entirely within the California Coast Ranges physiographic province and is underlain by two fundamentally different basement terranes of Mesozoic age: the Franciscan Complex and the Salinian block. The Salinian block is a northward-transported tectonic block of granitic and metamorphic rocks, covered in part by Cretaceous and Cenozoic sedimentary rocks. The map has been compiled from many scientific studies in different parts of the quadrangle, and represents the work of many geologists. Compilation of the Point Sur 30’ x 60’ quadrangle builds on compilation by the late Lew Rosenberg for the Monterey County General Plan (Rosenberg, 2001). Lew was working toward a completed geologic map in the format used for CGS regional geologic maps when he became ill in 2010. He passed away in 2013. This map represents an attempt to honor Lew’s legacy by completing the map he had so far along. Additional effort has gone into creating a single uniform nomenclature for the geologic units in the map area and incorporating new mapping published in the past few years. The map will be released for review and comments on the CGS web page: http://www.conservation.ca.gov/cgs/rghm/rgm/Pages/preliminary_geologic_map