ABSTRACT: Upper Devonian Sequence Stratigraphy of the Canning Basin, Australia: A Comparison with Coeval Carbonates in Southwestern Alberta

CHRISTIE-BLICK, NICHOLAS, and A. E. HOLMES,* Lamont-Doherty Geological Observatory of Columbia University, Palisades, NY

Global comparison of Paleozoic successions in a sequence stratigraphic context, making use of high-resolution biostratigraphy, offers a way of testing the idea that sedimentary cyclicity is driven by eustasy, and of establishing the timing of pre-Mesozoic eustatic fluctuations. Continuing seismic stratigraphic and outcrop studies in the Upper Devonian of the Canning basin, Australia, suggest the presence of as many as six sequence boundaries in the Frasnian and

four in the Famennian, a span of about 15 m.y. The most prominent and best dated of the Frasnian boundaries appear to lie (1) within the Prochorites (F2) goniatite zone of R. T. Becker et al. (in press), interpreted by them to be approximately equivalent to the upper part of the punctata conodont zone; and (2) within the Neomanticoceras (J) zone of Becker et al. (approx. lowermost rhenana zone). Three other sequence boundaries are tentatively identified in the lower Frasnian (below F2), along with a relatively minor boundary in the uppermost Frasnian (above J). Three or possibly four boundaries within the Famennian are not well dated, but they appear to be younger than the uppermost Cheiloceras zone (approx. marginifera zone).

In southwestern Alberta, sequence boundaries in the Palliser Formation may be equivalent to one or more Famennian boundaries in the Canning basin, and the one at the base of the Ronde Formation (uppermost rhenana zone) may correlate with the uppermost Frasnian boundary in the Canning basin. The prominent boundary at the base of the Sassenach Formation (triangularis zone of the Famennian) has no equivalent in the Canning basin, and boundaries within and at the base of the Peechee Formation (jamieae zone) appear to be slightly older than the one in the upper Frasnian J zone. We are not aware of evidence in the Cairn and Flume formations of Alberta for sequence boundaries equivalent to those within and below the mid-Frasnian F2 zone in the Canning basin. These conclusions require further evaluation to resolve uncertainties in both sequence stratigraphic and biostratigraphic interpretation, but comparisons such as this should provide insights about the origin of sequences and sequence boundaries that cannot be obtained in a single basin.

AAPG Search and Discovery Article #91012©1992 AAPG Annual Meeting, Calgary, Alberta, Canada, June 22-25, 1992 (2009)