to the National Atlas Home page
About | Fact Sheets | Contact Us | Partners | Products | Site Map | FAQ | Help | Follow us on Twitter 
Part of Project LogoAgricultureBiologyBoundariesClimateEnvironmentGeologyGovernmentHistoryMappingPeopleTransportationWater
to the Interactive Map MakerMap LayersPrintable MapsWall MapsDynamic MapsArticlesMapping Professionals

Map Maker
Geologic Map
Shaded Relief
Map Layer
Generalized Geologic Map of the Conterminous United States
North America Shaded Relief


  The North American Tapestry of Time and Terrain

The Two maps
Zoom In
Legend and Rock Ages
Rock Types
Political Boundaries

  Legend and Rock Ages

Cambrian Rocks - 540 to 505 million years ago

map of Cambrian rocks


The Cambrian is a period famous for its "explosion" of diversity in aquatic animal life. The first animals with hard skeletons appeared during this period. The most famous Cambrian rocks may be the Burgess Shale in the Canadian Rockies, which contain the rare fossils of soft-bodied animals.

Beside the Burgess Shale, Cambrian rocks are also present in features such as the Driftless Area and the Appalachian Valley and Ridge Province.