U.S. shale oil output to fall in May, first drop in four years - EIA

NEW YORK (Reuters) - Oil production from the fastest-growing U.S. shale plays is set to fall some 45,000 barrels per day to 4.98 million bpd in May from April, the first monthly decline in over four years, projections from the U.S. Energy Information Administration showed on Monday.

The projected slip from 5.02 million bpd in April underscores how record crude production from the U.S. shale boom may be backtracking after global markets saw prices effectively slashed by 60 percent since June on oversupply and lacklustre demand.

Oil production from the Permian Basin of West Texas and New Mexico were forecast to rise 11,000 bpd to 1.99 million bpd, the smallest monthly increase since November 2013, according to the EIA's drilling productivity report.

Production from the Bakken formation of North Dakota will fall 23,000 bpd to 1.3 million bpd. Eagle Ford oil production in South Texas will fall 33,000 bpd to 1.69 million bpd, the largest monthly drop since EIA began tracking the data in 2007.

Meanwhile, new-well oil production has accelerated as drillers look to squeeze more oil from rigs.

In the Eagle Ford, new-well oil production per rig rose by 20 bpd to 700 bpd in May. A month earlier, it rose by 22 bpd to 680 bpd, the fastest increase on record with the EIA.

Similarly, Permian new-well oil production per rig rose by 36 bpd to 240 bpd in April and by 25 bpd to 265 bpd in May, the fastest increases on record with the EIA.

Natural gas production in the major shale plays was expected to ease 23 million cubic feet per day to 45.97 billion cubic feet per day in May from April.

That is the first expected monthly decline in gas production from shale fields since July 2013, according to EIA data.

The biggest losses in May were expected in the Niobrara, down 50 mmcfd, Eagle Ford, down 45 mmcfd, and Bakken, down 21 mmcfd.

EIA expected the biggest growth in May in the Haynesville at 44 mmcfd and Utica at 35 mmcfd.

In Marcellus, the nation's biggest gas field centred under Pennsylvania and West Virginia, production was expected to rise just 10 mmcfd to 16.7 bcfd in May.

A year ago, production in the Marcellus was 14.4 bcfd.

(Reporting By Catherine Ngai and Scott DiSavino; Editing by Chris Reese and Marguerita Choy)