Oil production and natural gas production from the six prominent shale basins in the United States should increase in May, a U.S. drilling report said.

The U.S. Energy Information Administration issued a monthly drilling report for the six shale basins -- Bakken, Eagle Ford, Haynesville, Marcellus, Niobrara and Permian -- that together account for almost 90 percent of the growth in U.S. oil production and nearly all of the gains in natural gas.

For oil production from the shale basins, EIA expects a net increase of 71,000 barrels per day for 4.3 million bpd in May. The Eagle Ford shale area in Texas is expected to lead in terms of oil production with a 2.3 percent increase from April to May.
For natural gas, the administration said 38.9 billion cubic feet of gas per day should come from the six basins in May, a net change of 467 million cubic feet from April. The Marcellus shale in the Appalachian region leads with a 1.7 percent increase in production from April to May.

Shale exploration is controversial because some of the chemicals used in the process are viewed as an environmental threat.