B. S. Norford, 2012. "Middle Cambrian–Middle Ordovician Rocks of Western Canada, Latitude 49° to the Peace River", Great American Carbonate Bank: The Geology and Economic Resources of the Cambrian—Ordovician Sauk Megasequence of Laurentia, James Derby, Richard Fritz, Susan Longacre, William Morgan, Charles Sternbach
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Southwestern Canada was located in the tropics during the Cambrian and Ordovician, with the western part of the craton of the Canadian shield covered by shallow seas. Carbonates accumulated in these warm seas in the Middle Cambrian-Middle Ordovician, together with terrigenous detritus carried by rivers from the craton to the east. Thick carbonates developed in the outboard parts of the carbonate platform, facing the deeper waters of the bordering oceanic trough; thicknesses total some 4000 m (∼ 13,000 ft). The outboard edge of the carbonate platform varied in position with time. In the south, for most of the Middle Cambrian-Middle Ordovician, the edge was located just west of the present Alberta-British Columbia boundary as the Kicking Horse rim, the site of submarine topography and spectacular changes of facies from shallow-water carbonates to slope deposits and basinal sediments of mudrocks and clastics.
Nine grand cycles can be recognized within the Middle Cambrian to Middle Ordovician carbonates, with the top of each heralding a drop of sea level and a corresponding transgression. The formations of the carbonate platform thin to the east and northeast and have been beveled by several unconformities so that the stratigraphic package is only about 600 m (∼2000 ft) thick in the subsurface of southern Alberta and the northern Williston Basin.
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Great American Carbonate Bank: The Geology and Economic Resources of the Cambrian—Ordovician Sauk Megasequence of Laurentia
The Great American Carbonate Bank (GACB) comprises the carbonates (and related siliciclastics) of the Sauk megasequence, which were deposited on and around the Laurentian continent during Cambrian through earliest Middle Ordovician, forming one of the largest carbonate-dominated platforms of the Phanerozoic. The Sauk megasequence, which ranges upwards of several thousand meters thick along the Bank's margin, consists of distinctive Lithofacies and fauna that are widely recognized throughout Laurentia. A refined biostratigraphic zonation forms the chronostratigraphic framework for correlating disparate outcrops and subsurface data, providing the basis for interpreting depositional patterns and the evolution of the Bank. GACB hydrocarbon fields have produced 4 BBO and 21 TCFG, mostly from reservoirs near the Sauk-Tippecanoe unconformity. The GACB is also a source of economic minerals and construction material and, locally, serves as either an aquifer or repository for injection of waste material. This Memoir comprises works on biostratigraphy, ichnology, stratigraphy, depositional facies, diagenesis, and petroleum and mineral resources of the GACB. It is dedicated to James Lee Wilson who first conceived of this publication and who worked on many aspects of the GACB during his long and illustrious career.