List of Slides for Pinnacles NM
- The Pinnacles, located about 200 miles
south of San Francisco, are distinctively rugged landforms eroded from
layers of volcanic breccia of Miocene age.
- The volcanic rocks have been preserved in a fault block that moved
downward. Elsewhere, the volcanic layers have been eroded away, leaving
the jagged peaks of the Pinnacles within the
generally smooth topography of the Coast Ranges.