Early stimulation work in Peat Field of Queensland, Australia involved application of cavity completion techniques to produce methane gas at commercial rates in the first wells completed in the reservoir gas cap. Early in the project life, cavity completion treatments resulted in promising and acceptable gas flow rates. However, excessive cost associated with this technique led to consideration of alternate stimulation approaches by the design team. The main objective was to achieve similar or better gas rates at the lowest cost. Multi-seam nitrogen-foam stimulation was conducted in several wells of the Peat field to assess the effectiveness of this technique in terms of:production enhancement and cost reduction;location of the coal-seam intervals in the gas cap (i..e. gas-saturated coals) and;improved completion efficiency. To minimise the effects of tortuosity and multiple far-field fractures in addition to ensuring that each coal-seam interval received adequate treatment, a staged stimulation approach in combination with other remedies such as sand slugs and high injection rates was adopted and successfully applied. Zonal Isolation was achieved through the use of the newly developed, easily drillable composite plugs that allow staged treatment with flowback capabilities. Field data of representative Peat wells will be used to demonstrate the successful application of the hydraulic fracturing approach that resulted in methane gas rates that more than compete with the early cavity completion techniques either from a cost or production improvement point of view. The following specifics are addressed in the paper:A novel fracture design approach and modeling of fracturing treatments that can be of value to a broad audience of operators and design engineers.Real-time fracture stimulation methodology, analysis, and execution.Remedies to minimize the near-wellbore tortuosity and multiple far field fractures to avoid premature "screenout" and carry the fracture treatment to completion.Chemical optimization of fracture fluid designed based on coal characteristics.Use of newly developed composite epoxy-glass fracture and bridge plugs that provide a more efficient and cost effective way to carry out staged stimulation treatments.Post-fracture production tests to estimate the nitrogen-foam fracture treatment effectiveness in multi-seam CBM wells. Introduction The Peat field1 is located on the eastern edge of the Bowen Basin about 20 km east of the town of Wandoan (Fig. 1). The field is approximately 8 km wide and 26 km long and comprises Late Permian Baralaba Coal Measures overlying the Burunga Anticline, the largest anticlinal feature in the Bowen Basin. Aggregate net coal thicknesses range from about 7.1 m to 22.7 m over an interval of between 100 m to 140 m. Individual seam thicknesses range up to 13.7 m. Coal depths range from 600 m below ground and are currently being investigated to as deep as 1200 m. Within 15 km to the west coal depths reach over 2000 m.

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