Geology of Orange County and Vicinity
Speaker: Bill Neill
Date: January 15, 2015 (doors open 6:45 pm, Speaker at 7:30 pm)
Location: Duck Club, Irvine (Directions)
The geological history of coastal California is more complex and much younger than most of North America. This results from Southern California's location at the continent's edge, which has been a tectonic plate margin for about 220 million years. The most remarkable event was about 18 million years ago, when sideways movement starting on the proto-San Andreas Fault rotated the western Transverse Ranges, including the Santa Monica Mountains, about 120 degrees clockwise, away from the present coasts of Orange and San Diego Counties, thus forming the deep Los Angeles sedimentary basin.
For the January 15 program at the Duck Club in Irvine, Bill Neill will describe and illustrate the geology of Orange County, in relation to other regions of Southern California. This presentation will provide an introduction to the various sedimentary and volcanic rock units, which can influence native plant communities, and will make the structures and rock types more understandable to the casual observer.