If you've wondered what companies are tops in oil production in North Dakota, here's the list of the top 20 operators and the sums of their cumulative oil.
The cumulative oil is the amount companies have produced going back to the discovery of oil in the state more than 60 years ago and to the present time.
Preliminary figures for the state's oil production in November, the most recent figures available, was 21,992,345 barrels or 733,078 barrels a day, a slight drop from October and mainly because of the winter weather, according to the North Dakota Department of Mineral Resources in Bismarck.
North Dakota is No. 2 in oil production in the nation, a feat it achieved last year, and its all-time high was 749,212 barrels of oil per day in October 2012.
Following are the sums of cumulative oil for the top 20 operators. Other companies also are operating in the North Dakota oil patch. The information is provided by the N.D. Department of Mineral Resources and updated as of Thursday.
Hess Corporation 327,465,899
Whiting Oil and Gas Corp. 173,796,212
Denbury Onshore, LLC 140,381,459
Continental Resources, Inc. 130,205,244
Petro-Hunt, LLC 123,800,580
Burlington Resources Oil & Gas Co. LP 113,970,838
Amerada Hess Corp. 112,393,684
EOG Resources, Inc. 76,871,597
SM Energy Co. 75,180,729
Enduro Operating, LLC 57,738,630
Sequel Energy, LLC 45,051,477
Citation Oil & Gas Corp. 33,792,002
XTO Energy Inc. 30,837,723
Marathon Oil Co. 30,409,533
Texaco Exploration & Production Inc. 29,172,952
Slawson Exploration Co. Inc. 25,953,934
Murex Petroleum Corp. 25,860,050
Brigham Oil & Gas, L.P. 23,269,391
Encore Energy Partners Operating LLC 22,377,313
Williston Hunter ND, LLC 19,375,707
As of Friday, 187 rigs were actively drilling in the N.D. oil patch, according to the N.D. Oil and Gas Division, a divison of the N.D. Department of Mineral Resources.

