Geology

Geology. . [caption at upper left] , A 250 million year old fossilized sea shell found in the Pencader Area, Location, Delaware is the second smallest state in the country. However, we played an important role in the formation of the nation. Caesar Rodney rode from Lewes to Philadelphia to cast the deciding vote for independence in 1776. We were the first state to ratify the constitution in 1787., Piedmont Rocks (crystalline rocks): , Metamorphosed (changed by pressure and heat) sedimentary rocks of the ancient North American Continent and adjacent ocean basin., Wilmington Complex: , Igneous (formed by molten rock) and metamorphic rocks of a volcanic island arc that collided with the ancient North American continent during the convergence of tectonic plates (that formed the super coastal continent.), Atlantic Coastal Plain Rocks: , Sedimentary rocks of the Cretaceous Period (230 million to 63 million years ago) deposited over the eroded surface of the metamorphic basement rocks after North America drifted away from Africa and Europe to form the Atlantic Ocean basin., [start 2nd column] , Location, From Pencader Hundred shipping was possible by either the Delaware River or the Chesapeake Bay., One third of the population of the United States now lives within a day's drive of Pencader Hundred., The shortest distance overland between the Delaware River Watershed and the Chesapeake Bay was through Pencader [,] which made this area the hub of Mid-Atlantic travel., The Native Americans used the rivers in the two riversheds to travel from the Piedmont to the Coastal Plain for food gathering and the trading of furs and materials such as jasper from Iron Hill. Their trails passed through Pencader., As European settlements grew into cities, Pencader remained a center point, lying midway between Philadelphia and Baltimore, New York and Washington, Boston and Richmond. Thus, travelers between these early urban centers passed through the area on their way to and from these early centers of commerce. Much of today's commerce follows the same early routes., Location, North to South cross section of canal , 100 Million to 250 million years ago , 250 million to 550 million plus years, Generalized northwest to southeast geologic cross section across the Pencader Heritage Area (PHA), [start 3rd column] , Location, Fall Line , The Christina drops 350 feet in 15 miles from it's source near Kemblesville, Pennsylvania to Smalley's Dam. This provided the water power to operate grist and saw mills., Division between the Delaware River Watershed and the Chesapeake Bay Watershed, Typical Delaware fossils found along the canal , Exigyra Fossil , Belernnite Fossil, Chestnut , Hill , Iron Hill, [start timeline across bottom] , When did it happen?, 550 Million Years Ago , --- 550-350 Million Years ago , --- Volcanic action formation , --- of the Wilmington Complex , 250 Million Years Ago , --- 250 Million Years Ago , --- Global action formed , --- the Coastal Plain , --- around these two , --- formations , 12,000 Years Ago , --- 12,000 BC to 10,000 BC , --- Evidence that Native , --- Americans occupied the , --- Pencader Area during their , --- summer migration , 1638 A.D. , --- 1638: Swedes arrived on the , --- Kalmar Nyckel bringing European , --- agricultural practices to the , --- Pencader Area