The fourth bore of the Caldecott Tunnel opened to traffic on November 16, 2013, and if you’re an East Bay resident, chances are good that you’ve been through it once or twice (at least!). Did you realize that each time you drive through the tunnel you’re passing through several million years of accumulated sediment that has been pushed up on its side?

Want to know more about the rocks the tunnel cuts through and the fossils found in them? As part of an agreement between UCMP and the California Department of Transportation (Caltrans), the museum has created a web-based feature focusing on the geology and paleontology of the tunnel’s fourth bore. The feature covers …

… the tectonic history of the East Bay

… the geology of the East Bay Hills

… the preparations taken prior to excavation of the fourth bore

… the method and sequence of excavation

… and the fossils that have been prepared and cataloged (so far).