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

Dividing the Gulf of Mexico Basin into four provinces is the method of describing the
structural components (Figure 8). Division of provinces is according to the timing of
extension (Peel, et al., 1995). Vinton Dome falls within the Central Province, dominated
by isolated structural systems such as fault compartments and radial faulting associated
with diapirs surrounded by areas of relatively simple structures such as extensional
normal faults.
Understanding the relationships between salt flow and listric normal faults is essential in
deciphering the complex structure of Vinton Dome. Pressure gradients resulting from the
weight of overlying sediments are the source for salt flow in nonorogenic environments.
Basinward movement of sediments above some decollement surface generates listric
normal faults. In the Gulf of Mexico Basin, salt flow is a function of either differential
sediment loading or the creation of a density gradient produced by denser sediments on
top of less dense salt resulting in buoyant salt rise. Differential loading refers to the
situation that occurs when two adjacent vertical columns of sediment of different mass
cover a common level of salt and result from depositional variations. If sediments are less
dense, then salt will tend to move out from under the salt high into the adjacent salt.
Equal salt and sediment densities result in no salt movement. Higher sediment densities
drive salt out of the salt bed into the salt high (Figure 9). Lateral extension will spread
the salt and sediment layers over a larger area (Nelson, 1991).
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