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

loading and faulting are the major processes that typically affect the evolution of salt
bodies. Shown in Figure 5 (see below) are types of salt features recognized in the Upper
Continental Margin of the Gulf Coast Basin.
Salt body formation is generally in restricted basins and deposited as sub-horizontal beds.
Salt has a low density and yield strength, and will flow in the solid state by gravity alone.
Factors influencing flow are temperature, pressure, and the presence of impurities. Water
will increase diffusive flow and non-evaporite minerals will reduce plasticity. Salt flow
will result in the transformation of a tabular body into a variety of geometric structures.
Salt beds generally deform into concordant low-amplitude structures such as salt
anticlines, rollers and pillows that may evolve into discordant high-amplitude diapiric
structures such as salt walls, stocks, nappes, and detached teardrop units, and may
eventually form into extrusions (Figure 5) (Jackson and Talbot, 1986). Deformation can
stop at any time and reactivate at a later period. A diapiric structure is the reference to a
salt body that either pierces or appears to have pierced the overburden. A salt dome is the
term applied to diapirs such as salt pillows or stocks and their surrounding arched strata
(Jackson and Talbot, 1986).
Based on experimental modeling, one classification system of diapers is in three stages.
Reactive diapirs that initiate and grow under grabens formed by extension of the
overburden, active diapirs that rise by pushing aside thinned overburden, and passive
diapirs that grow by downbuilding (Vendeville and Jackson, 1992). Downbuilding
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