Discovery of pre-3.5 Ga exotic crust at the northwestern Superior Province margin, Manitoba

Abstract

Research Article| January 01, 2000 Discovery of pre-3.5 Ga exotic crust at the northwestern Superior Province margin, Manitoba Christian O. Böhm; Christian O. Böhm 1Department of Earth and Atmospheric Sciences, University of Alberta, 1-26 Earth Sciences Building, Edmonton, Alberta T6G 2E3, Canada Search for other works by this author on: GSW Google Scholar Larry M. Heaman; Larry M. Heaman 1Department of Earth and Atmospheric Sciences, University of Alberta, 1-26 Earth Sciences Building, Edmonton, Alberta T6G 2E3, Canada Search for other works by this author on: GSW Google Scholar Robert A. Creaser; Robert A. Creaser 1Department of Earth and Atmospheric Sciences, University of Alberta, 1-26 Earth Sciences Building, Edmonton, Alberta T6G 2E3, Canada Search for other works by this author on: GSW Google Scholar M. Timothy Corkery M. Timothy Corkery 2Manitoba Energy and Mines, Geological Services, 360-1395 Ellice Avenue, Winnipeg, Manitoba R3G 3P2, Canada Search for other works by this author on: GSW Google Scholar Geology (2000) 28 (1): 75–78. https://doi.org/10.1130/0091-7613(2000)28<75:DOPGEC>2.0.CO;2 Article history received: 26 Jul 1999 rev-recd: 04 Oct 1999 accepted: 13 Oct 1999 first online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Christian O. Böhm, Larry M. Heaman, Robert A. Creaser, M. Timothy Corkery; Discovery of pre-3.5 Ga exotic crust at the northwestern Superior Province margin, Manitoba. Geology 2000;; 28 (1): 75–78. doi: https://doi.org/10.1130/0091-7613(2000)28<75:DOPGEC>2.0.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 New U-Pb geochronological and Sm-Nd isotopic results across the northwestern margin of the Superior Province in Manitoba, Canada, require a major reinterpretation of the nature, structure, and location of the Superior–Trans-Hudson boundary in the area. A significant finding of this study is that an area northwest of Assean Lake, previously interpreted to be dominantly Early Proterozoic, contains ancient crust. Detrital zircon U-Pb results from two metagraywacke samples in this ancient crustal segment reveal ≥ 3.75 Ga source material, consistent with crustal residence Nd model ages (TCR) of 3.85 and 3.76 Ga, and the U-Pb zircon age for one tonalite gneiss sample is ca. 3.54 Ga (TCR of 3.63 Ga). This newly discovered pre-3.5 Ga crust provides the first evidence for the possible preservation of some very old rocks (pre-3.8 Ga) in this region, older than any known Superior Province crust. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.