Coalbed Mathane Enrichment Rule and Sweet Spot Optimization-Case Study from Australia North Bowen Basin

The Bowen Basin in Australia is a typical post-arc foreland coal-bearing basin. There are high Coalbed Mathane resource potential in the North Bowen Basin. The study block in this paper is mainly located in the North Bowen Basin and the Moranbah field was the first developed Coalbed methane field in this block. Combined with the structural characteristics of the North Bowen Basin, the characteristics of coal seam development, gas bearing characteristics and permeability of coal seams. There are following main controlling factors of Coalbed methane in Moranbah coal group, “Coal distributed by sedimentary factor, Coalbed methane accumulated by hydrological factor, Coalbed methane distributed by structural factor and Coalbed Methane permeability is controlled by stress factor”

On the basis of the law of coalbed methane enrichment rule, the optimization evaluation criteria are summarized. The Sweet Spot, the favourable area and the unfavourable area of the Bowen block are determined according to resources basics, enrichment factors and production factors. It is suggested that Sweet Spot should apply for development permit and begin to the trial production, the favorable area should apply for potential commercial area and block temporal preservation and waiting for future development, and the unfavorable area should apply for relinquishment.