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West African proximity of the Avalon terrane in the latest Precambrian

2001; Geological Society of America; Volume: 113; Issue: 9 Linguagem: Inglês

10.1130/0016-7606(2001)113 2.0.co;2

1943-2674

A. K. McNamara, Conall Mac Niocaill, Ben A. van der Pluijm, Rob Van der Voo,

Paleontology and Stratigraphy of Fossils

Research Article| September 01, 2001 West African proximity of the Avalon terrane in the latest Precambrian Allen K. McNamara; Allen K. McNamara 1Department of Geological Sciences, University of Michigan, Ann Arbor, Michigan 48109-1063, USA Search for other works by this author on: GSW Google Scholar Conall Mac Niocaill; Conall Mac Niocaill 2Department of Geological Sciences, University of Michigan, Ann Arbor, Michigan 48109-1063, USA, and Department of Earth Sciences, University of Oxford, Parks Road, Oxford OX1 3PR, UK Search for other works by this author on: GSW Google Scholar Ben A. van der Pluijm; Ben A. van der Pluijm 3Department of Geological Sciences, University of Michigan, Ann Arbor, Michigan 48109-1063, USA Search for other works by this author on: GSW Google Scholar Rob Van der Voo Rob Van der Voo 3Department of Geological Sciences, University of Michigan, Ann Arbor, Michigan 48109-1063, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Allen K. McNamara 1Department of Geological Sciences, University of Michigan, Ann Arbor, Michigan 48109-1063, USA Conall Mac Niocaill 2Department of Geological Sciences, University of Michigan, Ann Arbor, Michigan 48109-1063, USA, and Department of Earth Sciences, University of Oxford, Parks Road, Oxford OX1 3PR, UK Ben A. van der Pluijm 3Department of Geological Sciences, University of Michigan, Ann Arbor, Michigan 48109-1063, USA Rob Van der Voo 3Department of Geological Sciences, University of Michigan, Ann Arbor, Michigan 48109-1063, USA Publisher: Geological Society of America Received: 08 Mar 2000 Revision Received: 06 Jun 2000 Accepted: 19 Jun 2001 First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (2001) 113 (9): 1161–1170. https://doi.org/10.1130/0016-7606(2001)113 2.0.CO;2 Article history Received: 08 Mar 2000 Revision Received: 06 Jun 2000 Accepted: 19 Jun 2001 First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Allen K. McNamara, Conall Mac Niocaill, Ben A. van der Pluijm, Rob Van der Voo; West African proximity of the Avalon terrane in the latest Precambrian. GSA Bulletin 2001;; 113 (9): 1161–1170. doi: https://doi.org/10.1130/0016-7606(2001)113 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 SocietyGSA Bulletin Search Advanced Search Abstract Considerable debate surrounds the Late Neoproterozoic paleogeographic position of the Avalon terrane, specifically whether it was adjacent to West Africa or Amazonia. New paleomagnetic results from upper Neoproterozoic rocks in the Avalon terrane challenge the latter position. Samples collected from the ca. 580–570 Ma Marystown Group in the southern part of the Burin peninsula of Newfoundland, Canada, yield high-temperature magnetic components, including dual-polarity directions, which are considered to be primary, on the basis of positive fold and agglomerate tests. The resultant tilt-corrected inclination is 53°, representing a paleolatitude of deposition of 34° +8°/–7° for the Marystown Group. Given the likelihood that Amazonia and Laurentia were still juxtaposed around 580–570 Ma, the Marystown Group results reveal that the paleolatitude of Avalon is significantly lower than would be expected if it was part of Amazonia. In fact, Avalon was separated from northern Amazonia by at least 1100 km at ca. 580 Ma. If West Africa was juxtaposed to Amazonia, opposite Laurentia, by this time, these results place Avalon at the same paleolatitude as the northern margin of the West African craton. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.