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Reversal pattern and apparent polar wander for the Late Jurassic

1975; Geological Society of America; Volume: 86; Issue: 11 Linguagem: Inglês

10.1130/0016-7606(1975)86 2.0.co;2

1943-2674

Maureen B. Steiner, Charles E. Helsley,

Geological formations and processes

Research Article| November 01, 1975 Reversal pattern and apparent polar wander for the Late Jurassic M. B. STEINER; M. B. STEINER 1Institute for Geosciences, University of Texas at Dallas, Richardson, Texas 75080 Search for other works by this author on: GSW Google Scholar C. E. HELSLEY C. E. HELSLEY 1Institute for Geosciences, University of Texas at Dallas, Richardson, Texas 75080 Search for other works by this author on: GSW Google Scholar Author and Article Information M. B. STEINER 1Institute for Geosciences, University of Texas at Dallas, Richardson, Texas 75080 C. E. HELSLEY 1Institute for Geosciences, University of Texas at Dallas, Richardson, Texas 75080 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1975) 86 (11): 1537–1543. https://doi.org/10.1130/0016-7606(1975)86 2.0.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Tools Icon Tools Get Permissions Search Site Citation M. B. STEINER, C. E. HELSLEY; Reversal pattern and apparent polar wander for the Late Jurassic. GSA Bulletin 1975;; 86 (11): 1537–1543. doi: https://doi.org/10.1130/0016-7606(1975)86 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 A paleomagnetic study of the Upper Jurassic (Kimmeridgian-Tithonian) Morrison Formation near Norwood, Colorado, indicates the existence of thirteen polarity intervals. The seven reversed intervals occupy much more of the section than the six normal intervals, suggesting that during this time the dominant polarity was reversed. Pole positions were computed for each portion of the section where directions were tightly grouped. The pole positions form two separate groups directly related to the stratigraphic position in the section of the samples from which they were computed. The two mean pole positions for the Morrison Formation, 142.2°E, 61.4°N (dp = 4.0°, dm = 6.5°) and 161.8°E, 67.5°N (dp = 3.5°, dm = 5.0°), define a path which includes the Cretaceous pole positions for North America. The data indicate that the Jurassic apparent polar wander curve for North America is approximately a line of latitude (present-day coordinates) connecting published Triassic and Cretaceous pole positions. The data disagree with the commonly held view that the Jurassic portion of the North American apparent polar wander curve includes the present axial dipole. 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.