Local sea level rose and fell significantly during the ensuing Tertiary period of the Cenozoic era. During the Eocene gastropods and pelecypods were preserved in Westmoreland County. Foraminiferans were preserved in James City County. Miocene gastropods were preserved in York and James City Counties. Miocene pelecypods were preserved in York and James City Counties. Miocene vertebrates of Virginia included sharks and whales, which left teeth and bones respectively in York County. During the Quaternary, local mastodons were preserved associated with bodied of water.
