Five platforms installed near Padre Island in the Gulf of Mexico experienced scour of foundation material caused by strong littoral currents. Dish-shaped depressions were formed under each platform; some were twelve feet deep and the edges extended as far as sixty feet from the platforms. Laboratory research projects directed the design of an inverted filter which was installed at each platform. Design information and installation techniques are given. Submarine surveys following Hurricane Carla in 1961 found a minimum amount of filter material displaced and very little additional scour.
The Chevron Field is located in the Gulf of Mexico just offshore from Padre Island. It is approximately 25 miles southeast of Corpus Christi, and is east of Kingsville. Oil and gas wells are being produced from five platforms which are located 1 1/2 to 2 1/2 miles from the shore, where the water is approximately 40 feet deep.
During the installation or these platforms, foundation cores were taken to determine proper pile penetration. Cores could not be recovered from the upper soil layers due to its unconsolidated state; however, it was found that these layers consisted of fine sand with a few shells and a few clay stringers.
Approximately 2 1/2 years after the first platform was installed, divers who were working on a salvage operation reported that the sand had been scoured from beneath one of the platforms. Three platforms were in place at the time and the fourth was being fabricated.
