Loop currents in U.S. Gulf delay repair of Shell pipelines from Mars platform

Shell said it has delayed the shutdown of its Mars tension leg platform, or TLP, in the Gulf of Mexico to replace flex joints on both its oil and natural gas export pipelines because of strong loop currents in the area.

Shell, which earlier announced that the lines would be shut down in March to complete repairs, said March 9 that loop currents “affect the safe and effective diving operations that are essential to complete the flex joint repairs.”

Loop currents form when a portion of the Gulf Stream enters the Gulf of Mexico through the Yucatan Straits, flows north and turns east and south to exit the Florida Straits forming a “loop.”

“The loop current is a permanent oceanographic feature in the Gulf of Mexico and, at certain times of the year, can extend north far enough to impact deepwater lease blocks in the central Gulf of Mexico,” Shell said.

The Mars TLP, located on Mississippi Canyon block 807, was initially shut in last May when Shell discovered damage to the oil pipeline flex joint. Further inspections of the natural gas line showed signs of deterioration. Shell made temporary repairs to both lines while the flex joints were refurbished and production resumed in June.

“While a precise repair date is not known, Shell will continue to monitor the loop currents with the possibility that this work can begin in the mid-April to late-May timeframe,” the company said, adding that repairs would take about 14 days to complete.

Shell operates the Mars TLP with a 71.5 percent interest. BP has the remaining 28.5 percent interest in the project. Meanwhile, Shell said flex joint replacement at Shell’s Auger TLP on Garden Banks block 426 has been delayed to the June-July timeframe because much of the same equipment and resources needed at Auger will first be required at Mars.

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