Oil Rig – A-Brutus TLP
Brutus is a deepwater Tension Leg Platform (TLP) located in the Gulf of Mexico, 165 miles south west of New Orleans, Louisiana. It is owned and operated by Shell and was the first of their platforms designed to accommodate subsea tie-backs.
The Brutus oil field is located in Blocks 158 and 202 of the Green Canyon area of the Gulf. Its target reserves are in the Plio-Pleistocene sands which are located at a depth between 12,500 and 17,500 feet. It has estimated reserves of 250 million Barrels of Oil Equivalent (BOE) with a ratio of 70:30 oil to gas.
Development and Design
The discovery well for Brutus was drilled in Block 158 in December 1988. This was followed by an appraisal well in the same block in 1994, and a third well three years later. The Tension Leg Platform was installed in mid-2001.
The Brutus TLP stands in 2,985 feet of water and rises to an elevation of 3,250 feet from the seafloor to the top of the drilling rig. The hull of the platform consists of four steel columns, 166 feet high and 67 feet in diameter. The columns are connected by pontoons in a rectangular arrangement.
Twelve tendons were installed to secure the platform, each measuring 32 inches in diameter. Each tendon is 2,900 feet long, and three of them are secured to each corner of the platform. The total weight of the tendons is 7,500 tons.
The deck of the platform is 245 feet square and 40 feet high. It consists of five modules to accommodate the process, drilling operations, power supply, crew quarters and the well bay. The total weight of the deck modules is 7,650 tons.
In 2000, a total of eight wells were brought on stream producing an average of 25,000 barrels of oil and 35 million cubic feet of gas per day. At peak production, the field is expected to produce four to five times that amount.
Although the Brutus TLP was designed to operate as a standalone facility, it has the capability to accommodate tie-backs from subsea production facilities, like Glider in Green Canyon Block 248 which started production in July 2004. The Glider field is located seven miles from Brutus at a depth of 3,400 feet. It consists of two wells that are tied back to Brutus by a single six-inch flowline.
The oil from Brutus is pumped via a 20-inch pipeline to the South Timbalier 301B platform, and from there it is connected to the Amberjack System. A separate 20-inch pipeline is used to pipe gas to Ship Shoal 332.
In May 2016 over 2,000 barrels of oil spilled into the Gulf of Mexico near the Glider oil field, causing a two-by-thirteen-mile sheen that was visible 97 miles off the coast of Louisiana. Shell responded by shutting off all wells flowing into the Brutus platform while they conducted an investigation.
Shell proceeded with an inspection of their subsea facilities and flowlines to determine the cause. The company reported that they had isolated the leak and shut in production. There were no reported injuries from the incident.