One of the most unique elements of the Santa Monica Mountains is the tectonic forces that created them. About 14 million years ago volcanic activity broke out on a grand scale. Meanwhile The Pacific Plate continued to sub-duct beneath the North American Plate, forming the San Andreas fault which began slipping and sliding past the rest of North America. These and other forces ignited the building process of the Santa Monica Mountains. Uplifted by volcanic's and plate tectonics, some of this original sea bed now stands high and dry at the top of Corral Canyon.