| 3 - The First Outcrop |
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Greywacke/Shale layers tilted upper left to lower right The youngest of the sedimentary sequence in this area these interbedded sandstone and shale layers are extensively weathered and covered with lichen. Fresh pieces can be viewed in the broken rock at the base of the slope AND in the pavement gravel along the outcrop. These rocks would have formed the very upper portion of the sea floor sequence we will be walking through on this field trip.
These rocks were created, we believe, by large undersea landslides that carried the particles from the shallow waters off the western coast of California that was, at that time, in the area of the Sierra Nevada.