Fault Marked by Vegetation

This steep hillslope is on the path to the beach south of the Doda Ranch—which I will name Earthquake Beach. On the left, the sandstone and mudstone of the Gualala block is of early Miocene age (roughly 20 million years old). On the right, Franciscan graywacke and mélange is of Cretaceous and Jurassic age (roughly 150-200 million years old). The vegetation doesn't care about the age of the rocks, but rather about their water-holding properties and the nutrients they provide. (The different slope orientations probably have an effect too.) This same effect is visible on a much grander scale along the fault near Point Reyes.