A Deterministic Evaluation of eismic Fidelity using Velocity Modeling ...

established the Mississippi delta as the largest sedimentary source for the Gulf of Mexico
Basin (Winker, 1982). Migration of the ancestral depocenter was towards the east
beginning in the early to late Miocene (Curtis, 1970). At the same time, replacing the
Houston sediment dispersal axis was the Red River axis on the Texas/Louisiana border
(Manning, 1990). During this phase the fluvial-dominated Calcasieu delta prograded
onto the collapsing continental margin creating the principle lower Miocene depocenter
(Figure 28). These deltas advanced the continental margin up to 80km seaward
(Gallaway et al., 2000).
Middle Miocene in the Vinton Dome area was a shore-zone system connecting the
Corsair Delta to the west with the Mississippi Delta to the east (Figure 29). Like the
middle Miocene the late Miocene was a shore-zone system (Figure 30) with sediments
supplied by the Mississippi Delta and other smaller deltas such as the diminishing Corsair
Delta. Both the middle Miocene and upper Miocene have the structural components of
radial normal faulting and the absence of a major growth fault (Figures 31) to suggest
passive diapirism based on Nelson Figure 11.
2.8 Conclusions and Discussion
Several questions remain concerning Vinton Dome geology. Among these questions are
the timing of active and passive diapirism. Improvements in resolution and fidelity of the
3-D seismic enhanced imaging of the salt flanks. High fidelity also provides the ability to
measure the slope of the salt flanks. Using such measurements is Talbot's method to
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