Fault Striae, Alaska - Interpreted

The reason this image was included in the exercise was that the striae on the fault surface have different directions by some 30 degrees. Note also that the striae in the upper right corner show curvature. This is one reason that one orientation measurement is inadequate, and also indicates that movement directions can change. Can you figure out which of the two directions was later and which was earlier (and what would be your reasoning)? The shadows also indicate that to the left the slip surface undulates with an axis parallel to the adjacent fault striae - these are fault corrugations. The joint set is noted for completeness.

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