THERE AND BACK AGAIN: THE RECYCLING OF APPALACHIAN AND GRENVILLE SIGNATURES IN DZ U-PB RECORDS OF PHANEROZOIC NORTH AMERICA
This Appalachian and Grenville DZ signature subsequently occurs in U-Pb records of DZ in the Mesozoic and Cenozoic of North America, sourced by either primary or recycled terranes. For example, in eastern North America, primary Appalachian-sourced DZ in the Cenomanian Tuscaloosa and Paleocene Wilcox of Alabama and Mississippi comprise 85-90% of total DZ, overwhelming other age groups. Although diluted by other age groups, recycled Appalachian and Grenville DZ signatures persist in western North America and comprise >50% of DZ from west-to-east flowing Jurassic to Holocene rivers of the Western US. The long-term persistence of Appalachian and Grenville DZ in the Phanerozoic rock record of North America, and the abundance of primary Appalachian-sourced DZ compared to the relatively diluted signature of recycled DZ transported from the west, may help determine sediment sources for modern systems of North America.