Monteagle (Upper Mississippian) gas production in Morgan County, Tennessee, is stratigraphically controlled by several porous limestone zones. These zones may be partially controlled by regional structure, as penecontemporaneous minor faulting may have caused localized shoaling during deposition with a resultant oolitic limestone development. In addition, after lithification, minor structural deformation appears to have created secondary fracture permeability which enhances production.

Detailed stratigraphic mapping of the oolitic zones offers the best exploration guide. Mapping may be coupled with a regional tectonic evaluation to derive joint and fracture directions. Operators would benefit from obtaining accurate subsurface material in drilling productive zones, followed by detailed examination of cuttings.

Most common completion techniques in these fields include application of raw acids and/or explosives, both of which leave undesirable completions with rapid decline of deliverability. Use of delayed acid treatment is strongly indicated as well as hydraulic fracing with sand-propping where economically justified. The Monteagle gas, despite its under-pressure characteristics, presents a good economic potential for small operators who follow basic geologic concepts and use modern completion techniques.

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