Although production from Eagle Ford Shale wells drops dramatically in the first year, oil continues to gush from the South Texas basin as rigs become more sophisticated at pulling hydrocarbons from the ground.
Eagle Ford wells tend to decline by 60 to 70 percent in the first year, but the play continues to see significant surges in crude oil production, the U.S. Energy Information Administration said in a report released Monday.
That swell is primarily due to the growing precision and efficiency of horizontal drilling and hydraulic fracturing, a process in which drillers force sand, water and chemicals underground to free oil and gas particles trapped in dense rock formations, the EIA said.
“If you look at the rig count and the speed of drilling, those have remained stable,” Sam Gorgen, EIA operations research analyst, said in an interview with Fuel Fix. “(Producers) aren’t drilling more wells, they are drilling better wells. Higher producing wells.”
The EIA in March noted that the Eagle Ford led the nation in increased oil production per rig. New wells now pump more than 500 barrels of crude per day, up from 350 barrels in 2013, according to EIA data.
There are two key changes that seem to be driving increased output. First, drillers are using seismic and geologic data to more accurately pinpoint the optimum location along the horizontal portion of the well where they want to conduct a hydraulic fracture, Gorgen said. Instead of conducting 20 to 30 fractures spaced out along the well bore, drillers target a particular oil-rich area, a technique that some companies say has improved production rates and led to better returns on their investments, Gorgen said.
Eagle Ford shale producers have also started using more sand and proppants, or materials used to prop open the cracks caused by hydraulic fracturing. Injecting two to four times as much sand and proppants underground appears to boost initial production, but it also seems that wells decline more rapidly afterward, according to the EIA report.
It remains to be seen whether the expanded use of proppants will lead to long-term production increases, Gorgen said.
“It’s still uncertain what effect this sort of approach will have five or 10 years down the line,” he said.
In the Eagle Ford Shale, a success story for the industry in tight oil production, companies that are competing against each other to figure out how to pull more oil from wells are driving innovations in well efficiency that are now being applied to other plays like the Permian Basin, which is in the early stages of its life, Gorgen said.
“(Producers) have a lot more experience now, so they are able to take some of this knowledge and experimentation and implement that in other plays now,” he said.
In a state home to near half of all active land rigs in the United States, South Texas continues to dominate Texas’ oil industry, according to the Texas Railroad Commission, which regulates the state’s oil and gas industry.
The region is home to the top five crude-producing counties in the state, which combined produced 22 million barrels of crude oil in July. Karnes County, in the heart of the Eagle Ford, topped the list, producing 6.2 million barrels during the month, according to the Railroad Commission.
Surging Eagle Ford production contributed to the state’s ongoing robust drilling activity. The Railroad Commission issued 2,440 new drilling permits in August, a 50 percent increase over the same time last year, the state reported Monday.