File:M98Ch3Fig5.JPG

Refined biostratigraphic framework for the uppermost Cambrian and lowest Ordovician of Laurentian North America, showing 25 thin biostratigraphically discriminated intervals (alternating gray and white rectangles in the central column labeled B.D.I.) delineated through a combination of conodont and trilobite zonal or subzonal boundaries through the upper Sunwaptan, Skullrockian, and lowermost Stairsian Stages. Conodont and platform trilobite columns based on Miller et al. (2003), with informal numbered subzones in Rossodus manitouensis Zone from Lehnert et al. (2005). Zonations for deep-water faunas from southern (Iapetus) and northern (Panthalassa) Laurentian margins from Ludvigsen et al. (1989) and Westrop (1992), respectively.

From Taylor, John F., John E. Repetski, James D. Loch, and Stephen A. Leslie, 2012, Biostratigraphy and chronostratigraphy of the Cambrian–Ordovician great American carbonate bank, in J. R. Derby, R. D. Fritz, S. A. Longacre, W. A. Morgan, and C. A. Sternbach, eds., The great American carbonate bank: The geology and economic resources of the Cambrian–Ordovician Sauk megasequence of Laurentia: AAPG Memoir 98, p. 15–35.