Shale oil production in the United States is expected to jump again in July, marking the fourth straight month the Department of Energy has forecast monthly growth above 100,000 barrels a day.
The department's U.S. Energy Information Administration on Monday projected crude oil output will rise by 127,000 barrels a day next month in several of the nation's shale basins, where producers use advanced drilling methods like hydraulic fracturing to squeeze oil and natural gas from rock formations.
In July, total output from these resources is expected to reach nearly 5.5 million barrels a day, according to EIA.
Output growth in the shale fields has driven a 10 percent recovery in the country's overall crude production since September. More drillers can break even or turn a profit on new production since oil prices rose above $50 a barrel last winter, when OPEC and 11 other exporters agreed to cut their output in order to balance the market.
The biggest gains are once again expected to come from the Permian basin, the center of the U.S. oil recovery located primarily in western Texas and part of eastern New Mexico. EIA projects production in the Permian will rise by 65,000 barrels a day in July.
The Eagle Ford area is forecast to be the second biggest contributor to July's gains, with output expected to rise by 43,000 barrels a day next month in the southern Texas oil basin.
Production gains have been rising in the Permian as drillers become more efficient, squeezing more oil out of wells for each rig they deploy. But there are signs those efficiency gains may have reached their limit.
Production from new oil wells per rig topped out at 704 barrels a day in August, and is expected to fall to 602 barrels per rig in July.
This is happening in part because some drillers are moving beyond their best wells as more players pack into the Permian, according to IHS Markit analyst Raoul LeBlanc.
At the same time, the high demand for labor and equipment is causing producers to turn to workers who got laid off during the downturn and rigs that need investment after sitting idle. At the start of the recovery last year, a pool of workers and rigs that had not been out of the fields for long was still available, allowing production to rev up quickly early in the cycle.
"Technology marches in one direction. We're not getting dumber, but some of the cyclical factors will unwind. We'll see more of it particularly as costs continue to rise," LeBlanc told CNBC.
The drilling recovery is beginning to spread beyond the Permian and Eagle Ford to North Dakota's Bakken and the Niobrara, located in northeastern Colorado and parts of three adjoining states. EIA projects production will rise by 6,000 barrels a day in the Bakken and by 11,000 barrels a day in the Niobrara in July.
But production gains in these areas will be more muted than in the Permian, LeBlanc warned. A small number of specialist drillers are indeed increasing output, but there are just not enough players drilling in these regions to generate the kind of growth Texas is seeing, he said.
The EIA does not forecast output for the Scoop and Stack, two oil-producing regions in Oklahoma where activity has ramped up in recent years.
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