By Chester Dawson

North Dakota's crude-oil production in September dropped to the lowest level in more than two years on depressed prices, staying below the one-million-barrel-per-day mark for the second month in a row, the Department of Mineral Resources said Wednesday.

Crude production fell 1.1% on the month to 971,658 barrels a day in September, the most recent month for which data is available. That is the lowest level since February 2014, when output was 952,055 barrels a day, and follows a 4.7% drop in August.

North Dakota's production is centered on the Bakken Shale formation, one of the world's highest-cost oil fields. Prices below $50 a barrel -- half the level two years ago -- have forced shale-oil producers in plays like theBakken to slow drilling activity and curb output.

Total production in North Dakota was 29.2 million barrels of oil in September, down from 30.4 million barrels in August, the state said.

Natural-gas production in North Dakota fell 1.7% in September to 1.61 billion cubic feet a day, state figures showed. Energy producers burned off, or flared, 11.9% of gas output, up from 11.4% in August. Gas is a byproduct of oil production.

Most oil in North Dakota is extracted by hydraulic fracturing, or fracking, where a mixture of water, sand and chemicals is pumped into rock formations to push oil out. Such wells are first drilled and then put into production after being fracked, or completed.

Write to Chester Dawson at chester.dawson@wsj.com

(END) Dow Jones Newswires

November 16, 2016 14:43 ET (19:43 GMT)

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