Advances on land spill over to water
Offshore producers take note of onshore fracturing advances
High-horsepower pumps and big hydraulic fracturing trucks, the primary tools used to bust open U.S. shale rock, have carved out parking spaces of their own at the Offshore Technology Conference.
They’re an attraction for foreign onlookers interested in the technology that brought a rush of American oil to market. But more and more, they’re a jumping off point for oil producers looking to break open hard sandstone reservoirs found in deeper offshore fields, like at Chevron’s Jack/St. Malo project in the Gulf of Mexico.
Offshore producers have fractured conventional wells for decades, but advances in the landlocked U.S. shale industry have begun to bleed into the offshore side of the business.
As oil companies have waded into deeper waters, offshore fracturing work has gotten much bigger as producers have run into tougher rock comparable to hard sandstone in South Texas and the Anadarko Basin in Oklahoma and the Texas Panhandle, said Steve Szymczak, a director in Baker Hughes’ pressure pumping division, in an interview at Baker
Hughes’ booth at OTC.
“It’s a whole new frontier for the industry,” Szymczak said. Hydraulically fracturing a hard offshore sandstone reservoir can yield 40 times more oil from it. “It’s important to add the cost in order to get that prize.”
That’s why major oil field service companies like Baker Hughes and Halliburton have launched bigger hydraulic fracturing vessels in recent months.
Halliburton, the world’s largest hydraulic fracturing supplier, earlier this year christened the Stim Star IV vessel, a 312-footlong, 6,300-ton-capacity ship designed to handle multiple fracturing stages within an offshore well, as well as carry bigger pressure pumps and more proppant, the fine-grain sand or manmade material used to hold open fractures in a well.
Offshore fracturing jobs are smaller than onshore shale work, as the deep-sea rock is more permeable. It takes between 500,000 to 1 million pounds of man-made proppant to puncture an offshore well, compared with the 3 million pounds it takes on land. The rock isn’t as easy to pierce as the oilsoaked layers of sedimentation that have run down the Mississippi River into the Gulf and that are above the harder formations.
“It’s hard rock like the old days,” Szymczak said. “It’s a big challenge for the industry.”
If oil companies had to fracture at the same level of their peers on land, it wouldn’t be affordable in regions like the Gulf of Mexico, said Stephen Ingram, Halliburton’s director of business development for the Gulf of Mexico.
“The economics of reservoirs with extraordinarily low permeability doesn’t make sense offshore,” Ingram said.
Some shale-busting technologies on display, including those at the Schlumberger booth, have found their way offshore.
“They’ve done a lot of asset stimulation offshore, so it’s nothing new, but they’re bringing a lot of knowledge and technology we’ve learned from on land to the offshore market,” said Avo Keshishian, a product “champion” at Schlumberger.
“Given OTC’s global footprint and the number of clients that come from all across the world,” Keshishian said, “even if some don’t use it directly, they want to know about the technology, just given the importance of unconventionals right now in the market.”