Late Proterozoic-early Paleozoic crust in the Hermitage flexure, Newfoundland Appalachians: U/Pb ages and tectonic significance

Research Article| June 01, 1989 Late Proterozoic-early Paleozoic crust in the Hermitage flexure, Newfoundland Appalachians: U/Pb ages and tectonic significance G. R. Dunning; G. R. Dunning 1Department of Geology, Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario M5S 2C6, Canada Search for other works by this author on: GSW Google Scholar S. J. O'Brien S. J. O'Brien 2Geological Survey Branch, Newfoundland Department of Mines, P.O. Box 4750, St. John's, Newfoundland A1 C 5T7, Canada Search for other works by this author on: GSW Google Scholar Geology (1989) 17 (6): 548–551. https://doi.org/10.1130/0091-7613(1989)017<0548:LPEPCI>2.3.CO;2 Article history first online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation G. R. Dunning, S. J. O'Brien; Late Proterozoic-early Paleozoic crust in the Hermitage flexure, Newfoundland Appalachians: U/Pb ages and tectonic significance. Geology 1989;; 17 (6): 548–551. doi: https://doi.org/10.1130/0091-7613(1989)017<0548:LPEPCI>2.3.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Fault-bounded amphibolite facies gneisses at Grey River, southern Newfoundland, yield a U/Pb zircon age of 686 +33/-15 Ma for the magmatic protolith, whereas metamorphic titanite from the same sample has an age of 579 ±10 Ma. Lower grade felsic tuffs north of the gneisses yield an age of 544 ±5 Ma and, unlike the gneisses, contain inherited Middle Proterozoic zircons. In the Roti Bay-Cinq Cerf Bay area, lithologically similar gneisses are intruded postmetamorphically by a granitoid complex, from which two plutons yield U-Pb zircon ages of 499 +3/-2 and 563 ±4 Ma.These southern Hermitage flexure rocks are vestiges of a unique zone of late Precambrian-earliest Paleozoic crust, and they occupy a position intermediate between the lower Paleozoic Dunnage zone of the central mobile belt and the Precambrian Avalon zone. They may represent surface exposures of the seismically defined deep crustal block that underlies the eastern central mobile belt. These rocks can be correlated in age and tectonic position with rocks at the northwest margin of the Avalon zone elsewhere in the Canadian Appalachians and in Britain. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.