Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Selby, D. Articles by Creaser, R. A. Search for Related Content GeoRef GeoRef Citation

Direct radiometric dating of the Devonian-Mississippian time-scale boundary using the Re-Os black shale geochronometer

¹ Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta T6G 2E3, Canada, and Department of Earth Sciences, University of Durham, Durham DH1 3LE, UK
² Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta T6G 2E3, Canada

Many Phanerozoic time-scale boundaries are characterized by oceanic anoxia and mass extinction events with the deposition of black shale. The Re-Os isotope system in black shale can be used to provide depositional ages for these rocks, thus yielding direct radiometric ages for time-scale boundaries. We demonstrate that the Re-Os black shale geochronometer can yield precise ages useful for time-scale research through study of the Devonian-Mississippian boundary within the Exshaw Formation, Canada. The Re-Os date determined places the Devonian-Mississippian boundary at 361.3 ± 2.4 Ma (2 including uncertainty, model 1, mean square of weighted deviates = 1.2), in accord with recent calibration interpolated from U-Pb zircon dates (360.7 ± 0.7 Ma) for the Hasselbachtal section, Germany.

Key Words: Re-Os • black shale • geochronology • Devonian-Mississippian boundary

This article has been cited by other articles:

				G. W. Gordon, M. Rockman, K. K. Turekian, and J. Over Osmium isotopic evidence against an impact at the Frasnian-Famennian boundary Am J Sci, May 1, 2009; 309(5): 420 - 430. [Abstract] [Full Text] [PDF]

				B. Kendall, R. A. Creaser, and D. Selby Re-Os geochronology of postglacial black shales in Australia: Constraints on the timing of "Sturtian" glaciation Geology, September 1, 2006; 34(9): 729 - 732. [Abstract] [Full Text] [PDF]