Moonstone Beach Project

This project was conducted as part of the physical geology course (Geology 1) at College of the Redwoods. The project consists of mapping and analyzing outcrops located at Moonstone Beach.

Moonstone Beach is located in northwestern California, a few miles south of the town of Trinidad and approximately 30 miles north of the main College of the Redwoods campus (Eureka, CA). Outcrops and isolated blocks of the Jura-Cretaceous Franciscan Complex and overlying marine terrace deposits are exposed along this stretch of beach.

A location map and other documents used for this project are provided in the sidebar. References related to the geology of this site are also provided. This includes a description of similar Franciscan Complex rocks exposed near the Golden Gate Headlands in the San Francisco area.

The map embedded below provides place markers, photos and information describing Franciscan Complex outcrops. These Central Belt Franciscan rocks are Cretaceous in age (about 120 million years old). Also shown are the overlying, and much younger marine terrace deposits. The terrace deposits consist of sand and fossil rich layers.

This is an interactive map that allows one to zoom in and out, and move the view around. Click on the place markers to see information and photographs of the locations. You may have to move the map around to see the larger photographs.


View Moonstone Beach in a larger map