The MS 141 Geological Oceanography class traveled to the Marin headlands to visit many rocky outcrops.  The folded rock near rodeo beach San Francisco was most impressive.  This rock was around 300 million years old.  Composed of layer upon layer of radiolarian skeletons, tiny creatures with mineral bodies that get left behind, the outcrop has layers that span millions of years that have since been down-lifted, compressed and uplifted.  This is some rock that rocks!