I noticed the horizontal strata too. So I chose areas where the "shorelines" did not seem to be associated with outcrops. And I chose several where the outcrops are oriented differently from the shoreline occurrences. I can't be positive of my choices, and there may be better examples in the valley I didn't find. The only way to be positive is to get out there and walk the hills with a pick. Those studying the area are sure the shorelines exist.