Fold in Franciscan Melange, California Coast

These are folded layers of lithic wackes and cherts in part of the Franciscan melange (Goat Rock locality) exposed along the coast of northern California. You should note and trace the following: 1) one or two of the folded chert layers, 2) small veins within some of the folded chert layers, 3) an area where one of the sedimentary layer is notably thicker in the fold core (hinge) zone, and 4) smaller folds in the chert on the limbs of the larger folds.

Questions that may occur include the following. Why are the veins concentrated in the chert layers? What other differences are there between how the chert and the lithic wacke are deformed?

Link to interpreted version.

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