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Region: Northern Midcontinent
System: Pennsylvanian
Upper Missourian--Province Summary
This Upper Missourian Play information is from the
U. S. Geological Survey
1995 National Assessment of United States Oil and Gas Resources (available
on CD-ROM from the U.S.G.S. as Digital Data Series DDS-30, Release 2).
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Upper Missourian Oil and Gas Play
by Mitchell E. Henry and Timothy C. Hester
The Upper Missourian Oil and Gas Play consists of the upper part of the
Upper Pennsylvanian Lansing and Hoxbar Groups, which produce oil and gas
almost exclusively from limestones. The play extends throughout the
province except in parts of eastern Colorado and on the Wichita
Mountains Uplift. Depths to the top of the Lansing Group range from
about 2,800 ft in southeastern Colorado to about 11,000 ft in the deep
southern part of the play. The concentration of reservoirs in the
northern half of the play and the predominantly limestone lithology of
reservoir rock are the principal defining features of this play.
Reservoirs
Reservoir lithology in this play is generally limestone. Producing
intervals are usually identified only to the group level, however, two
examples of individual units included in the play are the Avant
Limestone and the Upper Oolitic lime (Daube Limestone). This play
ranges in thickness from less than 100 ft in the northern part of the
play to about 600 ft in the southern part of the play. Porosity
typically ranges from about 2 to almost 17 percent and has a median
value of about 15 percent.
Source rocks
Probable source rocks for this play are the Pennsylvanian shales in the
deeper parts of the basin. Modeling by Schmoker (1989) indicates that
petroleum generation may have begun as early as 210 Ma in the southern
part of the basin, but that potential source rocks in the Lansing Group
in the northern part of the play have probably not generated
hydrocarbons. For petroleum found in Upper Pennsylvanian reservoirs in
that area, Burruss and Hatch (1992) suggest long-distance migration
possibly from Simpson and Woodford shales. A more detailed description
of Pennsylvanian source rock characteristics is given in Burruss and
Hatch (1992). Timing of hydrocarbon generation and migration, and trap
formation is favorable for charging of reservoirs in this play.
Traps
Reservoir trap types are generally structural, commonly with a
stratigraphic component. Combination-type traps reportedly result from
local structure and porosity variability (Parham, 1993). Seals are
often formed by enclosing Lansing shales. Nearly all major
accumulations occur in the northwestern half of the play, the area that
is probably the least likely to have generated petroleum. This
distribution supports the idea of long-distance migration of petroleum,
and is probably related to better reservoir quality in the shallow
carbonates than in the basinward carbonates.
Exploration status
This is a well explored play. More than 24,000 wells are reported to
have reached the Lansing Group rocks. With the addition of wells that
reached Chesterian through middle Missourian rocks, where Lansing Group
tops were not identified, total number of wells in the Lansing Group
increase to nearly 75,000. Sixteen major accumulations are assigned to
this play, 11 oil and 5 gas. The largest oil accumulation is at Victory
field, with an estimated ultimate recovery of 17 MMBO. The largest gas
accumulation is at Southeast Falkner field, with an estimated ultimate
recovery of 28 BCFG. Known major accumulations range in depth from
3,800 to 5,600 ft.
Resource potential
Based on past successes that have been rather small and few, future
discoveries in this play are not expected to be significant. The large
number of wells that have been drilled does not indicate a high
probability for future discoveries. In addition, nearly all major
accumulations are in thermally immature areas on the northern shelf,
suggesting long-distance migration of hydrocarbons from a deeper source.
The lack of major accumulations in the more thermally mature areas may
also indicate a lack of traps or reservoir rocks or both. Historical
discovery and well completion data were used extensively in evaluating
this play.
Play Map
References
Burruss, R.C., and Hatch, J.R., 1992, Geochemistry of Pennsylvanian
crude oils and source rocks in the greater Anadarko basin--Oklahoma,
Texas, Kansas, Colorado, and Nebraska: An update [abs.], in
Johnson, K.S., and Cardott, B.J., eds., Source rocks in the southern
Midcontinent, 1990 Symposium: Oklahoma Geological Survey Circular 93,
p. 197.
Parham, K.D., and Sutterlin, P.G., 1993, Oolite shoals of the Mississippian
St. Louis Formation, Gray County, Kansas; a guide for oil and gas
exploration, in Keith, B.D., and Zuppann, C.W., eds., Mississippian oolites
and modern analogs: American Association of Petroleum Geologists, Studies in
Geology, no. 35, p. 185-197
Kansas Geological Survey, Digital Petroleum Atlas
Updated May 28, 1998
Comments to webadmin@kgs.ku.edu
URL=http://www.kgs.ku.edu/DPA/frontEnd/Anadarko/Missouri/provSum.html