A map showing the distribution of Great Valley Sequence and Franciscan Assemblage. Credit: Mikesclark/Wikimedia Commons Wikimedia Commons SA-3.0 Unported license

A map showing the distribution of Great Valley Sequence and Franciscan Assemblage. Credit: Mikesclark/Wikimedia Commons Wikimedia Commons SA-3.0 Unported license

A map showing the distribution of Great Valley Sequence and Franciscan Assemblage. Credit: Mikesclark/Wikimedia Commons Wikimedia Commons SA-3.0 Unported license

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