A photo of a lighthouse
By Geology and Ecology of National Parks
June 2011 (approx.)
Detailed Description
Point Bonita Lighthouse - Oceanside view of Point Bonita Lighthouse and the entrance to San Francisco Bay. This lighthouse on the Marin Headlands is built on bedrock consisting of diabase and basalt (late Mesozoic in age) (Elder, 2001; NPS, [2010]).
Sources/Usage
A photo of a lighthouse