Black gas shales are major parts of many foreland-basin sequences and comprise important components of unconformity-bound tectophase cycles, which reflect sedimentary/stratigraphic, flexural responses to deformational loading and relaxation in an orogen. Using as examples Upper Ordovician black gas shales, deposited during the Taconian orogeny in the Appalachian Basin of the eastern United States, black-shale origins and their importance in understanding the tectonic framework are discussed. Foreland-basin black shales are clearly the product of distinctive tectonic frameworks and histories, and aside from economic value, may provide important controls on the timing and location of tectonic events.
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Ettensohn, F. R. 1997. Assembly and dispersal of Pangea: Large-scale tectonic effects on coeval deposition of North American, marine, epicontinental, black shales. Journal of Geodynamics, 23, 287–309.
https://doi.org/10.1016/S0264-3707(96)00045-2
Ettensohn, F. R. and Lierman, R. T. 2015. Using black shales to constrain possible tectonic and structural influence on foreland-basin evolution and cratonic yoking: late Taconian Orogeny, Late Ordovician Appalachian Basin, eastern USA. In Sedimentary Basins and Crustal Processes at Continental Margins: From Modern Hyper-Extended Margins to Deformed Ancient Analogues (Gibson, G. M., Roure, F. and Manatschal, G., eds). Geological Society, London, Special Publications, 413, 119‒141.
https://doi.org/10.1144/SP413.5
Ettensohn, F. R., Pashin, J. C., and Gilliam, W. 2019. The Appalachian and Black Warrior basins: foreland basins in the eastern United States. In The Sedimentary Basins of the United States and Canada. 2nd ed. (Miall, A. D., ed.). Elsevier, 129–237.
https://doi.org/10.1016/B978-0-444-63895-3.00004-8
Kirschbaum, M. A., Schenk, C. J., Cook, T. A., Ryder, R. T., Charpentier, R. R., Klett, T. R. et al. 2012. Assessment of Undiscovered Oil and Gas Resources of the Ordovician Utica Shale of the Appalachian Basin Province, 2012. U.S. Geological Survey Fact Sheet 2012-3116.
https://doi.org/10.3133/fs20123116
