Start | View Uploaded Presentations | Author Index | Meeting Information

GSA Annual Meeting in Seattle, Washington, USA - 2017

Paper No. 120-3
Presentation Time: 8:45 AM

RIDDLE OF RODINIA: PALEOMAGNETISM OF THE CHUAR GROUP AND EVALUATION OF THE 780-720 MA LAURENTIAN APPARENT POLAR WANDER PATH


EYSTER, Athena E.1, WEISS, Benjamin P.2, KARLSTROM, Karl E.3, KREMERS, Jacob1 and MACDONALD, Francis A.4, (1)Department of Earth and Planetary Sciences, Harvard University, 20 Oxford St, Cambridge, MA 02138, (2)Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Building 54-724, Cambridge, MA 02139, (3)Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM 87131, (4)Department of Earth and Planetary Sciences, Harvard University, 20 Oxford Street, Cambridge, MA 02138, aeyster@fas.harvard.edu

During the Neoproterozoic Era (1000-541 Ma) the Earth experienced global glaciations, the diversification of crown group eukaryotes, and potentially a second great oxidation event, all of which are commonly associated with the breakup of the supercontinent Rodinia. However, both the paleogeography of Rodinia and the timing of continental separation remain poorly constrained. We report new paleomagnetic data from the 780-729 Ma Chuar Group of the Grand Canyon Supergroup, and refine the Laurentian apparent polar wander path through this critical interval to re-evaluate paleogeographic models for the makeup and breakup of Rodinia. The new poles are preserved in hematite and magnetite, and the primary nature of this paleomagnetic direction is supported by five of the seven Van der Voo (1990) reliability criteria. In addition to this primary direction, pervasive mid to high temperature overprints carried by hematite were identified. We incorporate these updated paleomagnetic poles with recent geochronological data and existing paleomagnetic data to present a new ca. 780-720 Ma Laurentian Apparent Polar Wander Path. Having examined the 780-720 Ma paleomagnetic database of other cratons, we present reconstructions for 780 Ma, 750 Ma and 720 Ma. Our new 780-720 Ma Laurentian apparent polar wander path is most consistent with a modified AUSMEX configuration, but we do not find an exact paleomagnetic match for the rifted margin from any major craton with constraints for 780-720 Ma.

Session No. 120

T252. Cratonic Assembly in the Precambrian: Forming the Core of Modern and Ancient Landmasses
Monday, 23 October 2017: 8:00 AM-12:00 PM
Room 604 (Washington State Convention Center)
Geological Society of America Abstracts with Programs. Vol. 49, No. 6
doi: 10.1130/abs/2017AM-308035
© Copyright 2017 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.
Back to: T252. Cratonic Assembly in the Precambrian: Forming the Core of Modern and Ancient Landmasses
<< Previous Abstract | Next Abstract >>