Smackover Formation Essay

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The Smackover Formation was deposited during the Upper Jurassic around 161 to 156 mya, during the Oxfordian Stage and is a part of the Louark Group. The end of the Louann Group is marked by a brief period of regression signifying the end of evaporite formation (Foote et al., 1988). “The Mid-Upper Jurassic is characterized by the graveled sandstones, conglomerates, and evaporite deposits of the Louann Salt and Norphlet Formations (Foote et al., 1988, p.14). These formations act as a base rock for the Smackover Formation to lie directly above. The deposition of the Norphlet Formation of East Texas is mainly affected by these structural constituents: “(1) Ouachita fold-belt, (2) Triassic/Jurassic grabens (likely associated with hydrocarbon traps) developed on the basin-ward flank of the fold-belt and (3) local paleo-highs” (Ryan et al., 1987, p. 458). Following the Norphlet Sandstone Formation is the transgressional events responsible for the Smackover Formation. …show more content…
The transgression event (Fig. 2) enables the deposition of marine sedimentary rocks atop the already existing sandstone and evaporite deposits, as well as, symbolizing the first widespread marine transgression event of the northern Gulf Coast (Walper and Miller, 1985). R.Q. Foote’s paper proposes that the Smackover was deposited during two separate sedimentological sea-level regimes, (Foote et al., 1988), resulting in two different depositional environments (Fig.2), characterized by the structural transition from an unrimmed platform to a carbonate ramp (D.T. King, 1994, personal