Published online by Cambridge University Press: 25 January 2017
San Nicolas is a small island located off the coast of southern California some 75 miles southwest of Los Angeles and 55 miles from the nearest point of the mainland. It is the most distant from the mainland of eight islands referred to collectively as the Channel Islands. San Nicolas is about 8 miles long by 4 miles wide and is 32.2 square miles in area. According to Norris (n.d., pp. 67-74), San Nicolas Island is a faulted asymmetric anticline composed of Pleistocene sediments lying unconformably on Eocene sandstone and shale. Original deposition during the Eocene was followed by anticline development and faulting in Eocene-Oligocene times. Miocene volcanic activity probably accounts for the several small diabase dikes on the island and for rhyolitic Begg Rock 7 miles northwest. The Pleistocene sediments were laid down during the first half of that period when the island was nearly or entirely submerged.
This report is based on a reconnaissance of San Nicolas Island made by the writers in January, 1953. The island is at present under the jurisdiction of the U. S. Navy, and permission to work there was obtained from the U.S. Naval Air Missile Test Center, Point Mugu, California. We are indebted to Captain E. M. Condra, Jr., commander of that station, for making the reconnaissance possible and for expediting the project in many ways. Appreciation is also expressed to A/s James V. Stallings and Ph/3c Claude D. Williams for their assistance on San Nicolas. Bibliographical information was supplied by R. J. Squier and A. R. Pilling of the University of California, Berkeley.
Particular mention is directed to Figures 34, 35, 36, 37 and 38 which are official United States Navy photographs. Permission to use these is appreciatively acknowledged.