WILLISTON LODGEPOLE ACTIVITY SPREADS

G. Alan Petzet
Exploration Editor

Oil discoveries are drawing numerous operators to a Mississippian Lodgepole play in the Williston basin.

The play is also stimulating significant 3D seismic acquisition aimed at helping operators pick out Lodgepole mounds about 10,000 ft deep.

Here is the approximate status of the play as of end-July:

About 40 wells have been drilled since early 1993 in the four townships 139n and 140n, ranges 96w and 97w, Stark County, N.D., with Lodgepole as primary objective. This drilling has resulted in discovery of five reefs - Dickinson, Knopik-Klein, Kuntz, Haller, and Hondl.

Several wells are still being drilled or evaluated, but at least 19 have produced commercially. That number includes two Conoco Inc. Dickinson field wells that have been converted to injection wells.

Daily production is 5,5006,000 b/d of oil, including about 4,000 b/d from Conoco's Dickinson Lodgepole unit. The fields are also producing an undetermined volume of casinghead gas.

Unitization is being sought for the Knopik-Klein area, and there is some thought that production from that area might be as much as 8,000-10,000 b/d when a unit is implemented.

Cumulative production from the play exceeds 2 million bbl, including more than I million bbl from Dickinson field and more than 500,000 bbl from discoveries by Duncan Oil Inc., Denver.

Six rigs are involved, including Duncan operating two and adding a third, Conoco operating one and adding a second, Armstrong Operating Inc., Dickinson, N.D., running one, and Meridian Oil Inc. about to field one.

The play is expected to stimulate new drilling in Manitoba, where several fields have produced oil from Lodgepole for years.

ACTIVITY GROWING

One of the newest entrants is TransTexas Gas Corp., Houston. The company said in late July it had acquired an 80% working interest in 110,000 net acres in Stark, Billings, and Dunn counties, N.D., including 1,100 acres near Dickinson, N.D. Phoenix Energy Cos. Inc., Dallas, holds the other 20%.

TransTexas said the acquisition included interests in acreage near the Armstrong 1-15 Hondl discovery well, in 15-139n-96w, and is near where Duncan has announced its intention to drill five wells.

TransTexas said it plans to acquire 31) seismic surveys on more than 160 sq miles to pick drilling locations in the carbonate reef fairway. It said it was seeking a permit to drill one well.

TransTexas noted the involvement in the play of Conoco, Shell Western E&P Inc., Amerada Hess Corp., Total Minatome Corp., and JN Exploration & Production Co., Billings, among many others.

LODGEPOLE DISCOVERIES

When completed in early 1993, Conoco's Dickinson field Lodgepole discovery was 70 miles from nearest Lodgepole production, the North Dakota Geological Survey reported.

Here are the Lodgepole discoveries completed since Conoco's Lodgepole deeper pool discovery in Dickinson field with the most recent successes listed first:

Armstrong and Summit Resources Ltd., Calgary, I Hondl, in 15-139n-96w. This well is thought to be another significant oil and gas discovery. Drilling was stopped to avoid penetrating the oil-water contact after the bit penetrated 80 It of an oil bearing reef. The well was cased after being drillstem tested. Later drilling will determine total oil column thickness, said Columbia Gas Development Corp., Houston, which holds a 50% working interest. It is 3 miles northeast of the 1 Haller.
Armstrong and Summit I Haller, in 29-139n-96w, located an estimated 20 million bbl of 44 gravity oil in place in Lodgepole at about 9,700 ft based on 31) seismic data and log analysis. It encountered 134 ft of net oil pay in a 303 ft Lodgepole section. Recovery factor is expected to be 40-65%.
Conoco Inc. 1 Kuntz, in 2-139n-97w, along the southwestern flank of Dickinson field, a discovery capable of producing at high rates and placed on restricted production last spring until hooked to a gas pipeline at midyear.
Duncan Oil Inc. I Knopik, in 11-139n-97w, which flowed as much as 2,707 b/d of oil and 1.55 MMcfd of gas. State figures show it produced 183,236 bbl of oil, 40.2 MMcf of gas, and 2,507 bbl of water during January through March 1995.