Photo of the Day - Feeling Crushed?

I took my physical geology students geotripping this week instead of their lab sections...Del Puerto Canyon cuts a deep swath through the eastern Diablo Range of Coast Ranges of California. In this single gorge, one can pass through a 6 kilometer thick section of the Great Valley Group (deposited within a forearc basin), a thick and nearly complete ophiolite sequence and underlying mantle peridotite (the Coast Range ophiolite), and a section of the Franciscan Complex (part of an accretionary wedge complex). How many places are there in the world where one can drive right through the crust into a subduction zone, and into the underlying mantle? The picture above is a section of highly deformed cherts of the Franciscan Complex.

Somewhere, Miss Frizzle and her magic school bus must be jealous....