The breakup unconformity of the Amerasia Basin, Arctic Ocean: Evidence from Arctic Canada

Abstract

Research Article| November 01, 1990 The breakup unconformity of the Amerasia Basin, Arctic Ocean: Evidence from Arctic Canada ASHTON F. EMBRY; ASHTON F. EMBRY 1Geological Survey of Canada, 3303 33rd St NW, Calgary, Alberta, Canada T2L 2A7 Search for other works by this author on: GSW Google Scholar JAMES DIXON JAMES DIXON 1Geological Survey of Canada, 3303 33rd St NW, Calgary, Alberta, Canada T2L 2A7 Search for other works by this author on: GSW Google Scholar GSA Bulletin (1990) 102 (11): 1526–1534. https://doi.org/10.1130/0016-7606(1990)102<1526:TBUOTA>2.3.CO;2 Article history first online: 01 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 ASHTON F. EMBRY, JAMES DIXON; The breakup unconformity of the Amerasia Basin, Arctic Ocean: Evidence from Arctic Canada. GSA Bulletin 1990;; 102 (11): 1526–1534. doi: https://doi.org/10.1130/0016-7606(1990)102<1526:TBUOTA>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 SocietyGSA Bulletin Search Advanced Search Abstract To delineate more closely the age and evolution of the Amerasia Basin of the Arctic Ocean, a breakup unconformity has been identified in sedimentary basins along the Canadian margin of the basin on the basis of one or more of the following criteria. (1) Strata underlying such an unconformity are cut by major normal faults which extend into the basement, whereas strata overlying the unconformity are relatively unfaulted. (2) A major decrease in subsidence rate in the marginal basins coincides with the time of breakup and the formation of the unconformity. (3) Volcanic rocks occur beneath the unconformity. The widespread late Albian-Cenomanian unconformity is interpreted to be the breakup unconformity and thus this time interval would coincide with the initiation of sea-floor spreading in the Amerasia Basin. Sea-floor spreading and the opening of the Amerasia Basin by the counterclockwise rotation of northern Alaska and adjacent northern Siberia away from the Canadian Arctic Islands are interpreted to have occurred during Late Cretaceous time and to have ceased near the Cretaceous-Tertiary boundary when the active plate margin switched to the site of the present Eurasia Basin. 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.