EVOLUTION OF GIANT SALT PILLOWS IN THE DESTIN DOME AREA, EASTERN GULF OF MEXICO: IMPLICATIONS FOR PETROLEUM EXPLORATION AND GEOLOGIC CO2 STORAGE
Models of total effective subsidence document diachonous salt pillow development, with loci of pillow formation migrating northward and eastward through time. Pillow Formation began during the Early Cretaceous with accumulation of salt in an arcuate ridge composed of elongate salt pillows. By the Late Cretaceous, pillow formation was restricted to the northwestern part of the ridge. Destin Dome structure did not grow significantly until the Late Cretaceous.
Thermally mature source rocks are restricted to the Jurassic Smackover Formation, which reached maturity and expelled most hydrocarbons during the Early Cretaceous. Several salt-cored anticlines have yet to be tested. Jurassic eolianite is productive in stratigraphic traps in Destin Dome that were apparently charged prior to formation of the structure. Younger strata in the dome have to date been subeconomic. Analysis of CO2 storage potential indicates that the same sandstone units that hosted pilot programs onshore are present in the dome, as are the same sealing strata. Crestal faulting is a significant geologic risk factor and thus is an important consideration for screening candidate storage sites.