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An excellent animation showing a combination of physical and numerical modeling of this type of salt movement process is at http://www.beg.utexas.edu/indassoc/agl/animations/AGL96-MM-002/index.html. Note that much of the Gulf of Mexico Salt is considered to be Louann Salt, which is of Jurassic age (144-192 million years ago). If salt in a mini-basin moved into a central dome and raised it vertically 0.005 feet per year since the beginning of the Miocene (5-24 million years ago), it would reach the 25,000 elevation change illustrated in Figure 44. This rate of growth implies there has been less than 30 feet of vertical movement on this salt dome over the 6,000 years mankind has had written language. This disconnect of time scales illustrates why the geological is a thing to be acted upon.
Even though salt tectonics are a minor part of the geologic record, several times my career as an earth scientists has been tied to studying salt induced structures. I have mapped horizons over, against, and under numerous salt domes in the Gulf Coast. At Mobil Oil I consolidated the interpretations made to support the first Brazilian lease sale back in about 1977. There are major salt domes in the Campos Basin east of Rio de Janeiro, which were included in these studies. These salt domes are analogous to and part of the same geologic system as the salt domes in Gabon and to a lesser degree in Angola on the west coast of Africa. The salt was probably generated when the African and South American plates separated. Most of my work in West Africa has been in Nigeria, where there are giant shale domes, which have similarities to the salt domes.
I was once involved in interpreting salt pillows (little salt domes) offshore Israel, and have seen data across the salt provinces offshore Egypt. I also reviewed data across salt structures in China. As consultants for BHP Petroleum, several of us mapped sub-salt structures in the Gulf of Mexico, and BHP bid on and won over 70 Federal Leases offshore Louisiana based on this work.
At Continuum Resources we built a virtual model of the U.S. Strategic Petroleum Reserve site at the Big Hill Salt Dome in Southeast Texas. In this salt dome there are 19 caverns. Each cavern is about 1,800 feet (550 meters) tall and 165 feet (50 meters) in diameter. These caverns are where petroleum is stored for a national emergency.
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paradoxes