Chronology of Paleozoic metamorphism and deformation in the Blue Ridge thrust complex, North Carolina and Tennessee

Insights into southern Appalachian tectonics from ages of detrital monazite and zircon in modern alluvium

“…Hornblende 40 Ar-39 Ar plateau ages in the study area range from 410 to 450 Ma (Dallmeyer, 1975;Kunk et al, 2006), but variably disturbed hornblende isotopic systematics are widespread (Goldberg and Dallmeyer, 1997). The Rb-Sr and Sm-Nd mineral-rock isochrons from samples in the vicinity of the Lick Ridge eclogite support the interpretation of Middle Ordovician regional metamorphism with variable Devonian resetting (Goldberg and Dallmeyer, 1997).…”

“…Hornblende 40 Ar-39 Ar plateau ages in the study area range from 410 to 450 Ma (Dallmeyer, 1975;Kunk et al, 2006), but variably disturbed hornblende isotopic systematics are widespread (Goldberg and Dallmeyer, 1997). The Rb-Sr and Sm-Nd mineral-rock isochrons from samples in the vicinity of the Lick Ridge eclogite support the interpretation of Middle Ordovician regional metamorphism with variable Devonian resetting (Goldberg and Dallmeyer, 1997). Musco vite on June 3, 2011 geosphere.gsapubs.org Downloaded from 40 Ar-39 Ar plateau and Rb-Sr mineral-rock isochron ages throughout the entire study area are generally Carboniferous (Dallmeyer, 1988;Connelly and Dallmeyer, 1993;Goldberg and Dallmeyer, 1997;Kunk et al, 2006).…”

Rate of growth of the preserved North American continental crust: Evidence from Hf and O isotopes in Mississippi detrital zircons

“…The Appalachian orogeny to the southeast of Laurentia is generally considered to be the product of five discrete tectonomagmatic events: Avalonian-Carolinian (580-640 Ma), Potomac ($500 Ma), Taconian ($430-500 Ma), Acadian ($350-400 Ma) and Alleghanian ($265-325 Ma) (Hatcher, 1989;Hibbard and Samson, 1995;Goldberg and Dallmeyer, 1997). These five late Neoproterozoic/Paleozoic events were associated with the amalgamation of Laurentia and Pangea (Eriksson et al, 2003).…”

Resolving the timing of orogenesis in the Western Blue Ridge, southern Appalachians, via in situ ID-TIMS monazite geochronology

“…Appalachian high-grade metamorphism and deformation have been traditionally ascribed to progressive southeast-younging orogenic events that resulted from closing of ocean basins between Laurentia and other landmasses during the early Paleozoic (Hatcher, 1987(Hatcher, , 1989Hatcher and Goldberg, 1991;Hibbard and Samson, 1995;Goldberg and Dallmeyer, 1997). These events have been recognized as the Taconian (ca.…”