Openhole cavity completions in coalbed methane wells in the San Juan basin

Journal Article · Mon Nov 01 00:00:00 EST 1993 · JPT, Journal of Petroleum Technology; (United States)

DOI:https://doi.org/10.2118/24906-PA· OSTI ID:5814567

Palmer, I D; Volz, R F; Seidle, J P ^[1]; Spitler, J L ^[2]; Mavor, M J

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1. Amoco Production Co., Tulsa, OK (United States)
2. Amoco, Durango, CO (United States)

Coalbed methane wells in the San Juan basin can be highly profitable, with gas production up to about 10 MMcf/D at depths of about 3,000 ft, if the wells are successfully completed with the openhole cavity technique. The authors report the first measurement of cavity size (radius of about 5 ft) and shape. A vanity can resemble a cylindrical bookcase with shale ledges like shelves. They also report correlations between successful cavity completions and such reservoir/rock parameters as compressive strength, coal rank, permeability, and reservoir pressure (for example, there is no correlation with the minimum coal compressive strength). In this area, wells completed with the openhole cavity technique often produce roughly 10 times more gas than wells completed with hydraulic fracture stimulations. Wellbore mechanics associated with the cavity--e.g., the enlarged wellbore plus enhanced permeability beyond the cavity--does not seem to explain the cavity/fracture production discrepancy. A number of other possibilities are explored, including permeability anisotropy and completion damage to the reservoir or fracture. Severe damage apparently is associated with hydraulic fracture stimulations in the fairway zone, which would explain their poor performance compared with cavity wells.

• OSTI ID: 5814567
• Journal Information: JPT, Journal of Petroleum Technology; (United States), Vol. 45:11; ISSN 0149-2136
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
01 COAL, LIGNITE, AND PEAT
COAL SEAMS
DEGASSING
COLORADO
NATURAL GAS WELLS
WELL COMPLETION
NEW MEXICO
COAL RANK
COMPARATIVE EVALUATIONS
COMPRESSION STRENGTH
COST
EXPERIMENTAL DATA
HYDRAULIC FRACTURING
METHANE
PERMEABILITY
PRODUCTION
RESERVOIR PRESSURE
RESERVOIR ROCK
ALKANES
COAL DEPOSITS
DATA
DEVELOPED COUNTRIES
EVALUATION
FRACTURING
GEOLOGIC DEPOSITS
HYDROCARBONS
INFORMATION
MECHANICAL PROPERTIES
MINERAL RESOURCES
NORTH AMERICA
NUMERICAL DATA
ORGANIC COMPOUNDS
RESOURCES
USA
WELLS
030300* - Natural Gas- Drilling
Production
& Processing
012033 - Coal
Lignite
& Peat- Underground Mining- Mine Environment- (1987-)