Allostratigraphy of the Upper Ordovician Blue Mountain Formation, Southwestern Ontario, Canada
Master of Science
Dr. Burns Cheadle
The Upper Ordovician units in Southwestern Ontario record the distal response to the development of the Taconic Appalachian foreland basin. The proximal representation in Ohio and Pennsylvania, contain the Utica/Point Pleasant Play (!). The relationship between the proximal and distal portions of the Taconic Appalachian foreland basin is not clearly defined due to limited chronostratigraphic data and only lithostratigraphic correlations in southwestern Ontario. The first step in evaluating the relationship between the Upper Ordovician succession in Ontario and that in the United States is to develop a high frequency allostratigraphic framework that can be integrated and compared to the frameworks in Ohio and Pennsylvania.
The application of allostratigraphic principals allowed for four developments: 1. The subdivision of the Upper Ordovician units in southwestern Ontario into four alloformations, and further dividing the Blue Mountain Formation into a high resolution allostratigraphic hierarchy consisting of two alloformations and nine allomembers. 2. The development of twenty cross-sections in southwestern Ontario using digital well logs and core to correlate the allostratigraphic units, 3. The creation of subsurface elevation and isopach maps, defining structure and extent of the allomembers in subsurface, 4. Identifying the Algonquin Arch as a mobile feature during the Upper Ordovician, responding to the loading and unloading of the Taconic orogenic front and the resulting clastic wedge in the Appalachian Basin.
These four developments create a platform for future work towards evaluating the temporal relationship between, and defining the vertical and lateral extents of, a Utica-equivalent petroleum system and associated plays in southwestern Ontario in the Appalachian Basin.
Sweeney, Sarah N., "Allostratigraphy of the Upper Ordovician Blue Mountain Formation, Southwestern Ontario, Canada" (2014). Electronic Thesis and Dissertation Repository. 2555.