NIOBRARA GAS INDICATIONS COVER WIDE AREA OF WESTERN NEBRASKA

May 11, 1992
Raymond R. Burchett Nebraska Geological Survey Lincoln The Niobrara formation was named in north-eastern Nebraska by Meek and Hayden1 for exposures along the Missouri River bluffs near the town of Niobrara in Knox County (Fig. 1). Distribution of the Niobrara is restricted to the western four fifths of Nebraska. Much of the formation is concealed by deposits of older Cretaceous, Tertiary, and the younger Quaternary age rocks. Exposures of the Niobrara occur in the south-central, east-central,
Raymond R. Burchett
Nebraska Geological Survey
Lincoln

The Niobrara formation was named in north-eastern Nebraska by Meek and Hayden1 for exposures along the Missouri River bluffs near the town of Niobrara in Knox County (Fig. 1).

Distribution of the Niobrara is restricted to the western four fifths of Nebraska.

Much of the formation is concealed by deposits of older Cretaceous, Tertiary, and the younger Quaternary age rocks. Exposures of the Niobrara occur in the south-central, east-central, northeastern, and northwestern parts of the state.

STRATIGRAPHY

The Niobrara is divided into two members (Fig. 2). The upper Smoky Hill chalk 2 is named from the Smoky Hill River in Kansas, and the lower Fort Hays limestone 3 named for historic Fort Hays in western Kansas.

The Smoky Hill consists mainly of yellow, lead-gray, and orange shaly to chalky limestone with some interbedded bentonite. It ranges in thickness from a feather edge in western Nebraska to more than 450 ft in southwestern Nebraska.

The Fort Hays limestone consists mainly of massive gray to yellow chalky limestone and ranges in thickness from a feather edge in eastern Nebraska to more than 40 ft in western Nebraska.

The contact of the Smoky Hill and the Fort Hays is gradational and sometimes difficult to recognize. The Graneros shale underlies Niobrara, and the Pierre shale overlies it.

The combined thickness of the Niobrara ranges from a feather edge in eastern Nebraska to more than 500 ft in southwestern Nebraska (Fig. 3). This formation and older rocks down to the Dakota group are eroded and missing over the top of the Chadron-Cambridge arch in northwestern Nebraska.

A map on top of the Niobrara (Fig. 4) shows its configuration to range from more than 1,000 ft below sea level in the Denver basin of western Nebraska to more than 3,000 ft above sea level on top of the Chadron-Cambridge arch in the northwestern part of the state.

Depth to the top of the Niobrara from the land surface ranges from zero in eastern and northwestern Nebraska to more than 6,500 ft in the Denver basin of western Nebraska (Fig. 5).

GAS PRODUCTION

Shows of gas in the Niobrara formation were reported in the early 1900s near the town of Goodlin, Kan. 4

However, no completions were attempted, and it was not until 1921 when Beecher Island gas field was discovered in Yuma County, Colo., by Midfields Oil Co. 5 that interest stirred in the Niobrara formation.

Several small Niobrara gas wells were reported drilled in the Goodlin field area of Kansas during the 1930s and 1940s, but they were completed only for local use.

Commercial development from the Niobrara did not start in the Midcontinent until 1972, when several wells were drilled and completed in Beecher Island field. Leasing programs resulted from these successful wells and extended from Colorado into Nebraska.

Many wells have been drilled through the Niobrara formation since the discovery of oil and gas in the panhandle of western Nebraska in 1949.

It was not until Feb. 27, 1978, when the I Smith in 9-15n-43w, Garden County, was completed as a shut-in gas well.

The well, drilled by Fremont Energy and Voyageur Exploration Co., flowed 285 Mcfd of gas and 50 b/d of water from the Smoky Hill member of Niobrara at 2,670-90 ft.

Including the 1 Smith, 75 Niobrara wells have been shut-in or plugged and abandoned since 1978 after having production casing set (see table).

In late 1991 and early 1992 Snyder Oil Corp., Fort Worth, completed four producing gas wells in the Smoky Hill member of Niobrara (Fig. 6).

The wells are the 17-14A Miller, SE SW 17-16n-47w; 19-2A Weyerts, NW NE 19-16n-47w; 20-4A Jessen, NW NW 20-16n-47w; and 20-8A Jessen, SE NE 20-16n-47w.

These wells are located in the Denver basin about 15 miles northeast of Sidney, Neb., in Cheyenne County.

It is reported that several other shut-in wells in the area may be placed on production.

REFERENCES

  1. Meek, F.B., and Hayden, F.Y., Proceedings of the Academy of Natural Sciences, Philadelphia, Vol. 13, December 1861, pp. 415-447.

  2. Cragin, F.W., On the stratigraphy of the Platte series or Upper Cretaceous of the Plains, Colorado Coll. Studies, Vol. 6, 1896, pp. 49-52.

  3. Williston, S.W., The Niobrara Cretaceous of western Kansas, Kansas Academy Science Transactions, Vol. 13, 1893, pp. 107-111.

  4. Brown, C.A., and Crafton, J.W., The Niobrara play: exploration and development of a low pressure, low permeability gas reservoir, presentation at American Gas Association/Stanford University joint symposium, Analytical, Techniques and Applications for Natural Gas Reservoirs, 1978.

  5. Lockridge, J.P., Beecher Island field, Yuma County, Colo., Rocky Mountain Association of Geologists Symposium Guidebook, 1977, pp. 271-279.

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