Coastal Salt Structures

In the gulf coast region, vast salt deposits formed from an ancient evaporating sea in the Jurassic period (162 million years

ago). Around the time of the Cretaceous-Paleogene extinction event (66 million years ago) the Mississippi delta began to extend Louisiana’s land mass southward, covering pockets of deposited salt. Over the years, this salt punctured through the overlying layers of river sediments into domes that host oil and gas deposits. Given their associated resources, these salt structures are economically and culturally important to the gulf coast. Revealing their extent across Southern Louisiana exposes the scale and magnitude of related industrial activities. Caverns exist within most salt domes across Louisiana. Some are the result of shaft and room mining techniques whereas other excavations are specifically designed to store hundreds of millions of barrels of oil as part of the Nation’s strategic petroleum reserve. As geological structures, the scale involved is near impossible to model in the laboratory resulting in full-scale tests executed in the field. The Napoleonville Oxy 3 Cavern, located more than 5,000 feet below the surface, collapsed from being too close to the edge of salt. This event resulted in a 37 acre sinkhole on the surface, mimicking the geometry of the underlying collapsed structure, giving us a surfacial representation of these massive subsurface systems.