The US Shale Gas "Revolution": A Review of the Production Performance and Geology to Establish Potential Economic Benchmarks for Australia

Abstract

Abstract Shale plays have created the current natural gas boom in the United States (US) and according to the national Energy Information Administration (EIA, 2013)49 produced 47% of total daily production by the end of 2013 (approximately 31.8 Bscf/d). Extensive production data from thousands of wells are now available for analysis to provide potential benchmark information for the Australian shale gas industry, which is still in its infancy. This paper focusses on analysis of publicly available US production data from horizontal wells in five depositional basins reported for the Barnett, Eagle Ford, Fayetteville, and Haynesville shale plays. Type-wells are evaluated which allow estimation of a range of representative initial gas production rate and technical Estimated Ultimate Recovery (EUR) characteristics. The analysis also results in generic recommendations for the minimum sample size and duration required for statistically significant well appraisal programs in shale plays. Such activity phases' primary objective should be to efficiently obtain reasonably reliable type-well performance indicators. The US shale plays' experiences to date provide insight concerning this aspect. Variability in geological factors including, but not limited to: stress regime, total organic content, thermal maturity, porosity, brittleness, natural fractures, and reservoir pressure can result in production performance that differs substantially both within and between shale plays. Also affecting performance is how the wells are completed. The geology of shale formations is discussed along with recent Australian operational activity, geomechanical considerations, and example economics. Analyses of the US data provide potential technical and economic benchmarks for preliminary comparisons to be made with Australian information, and may help to demonstrate the economic resilience required for exploitation of prospective shale gas resources. However, it must be recognised that the likely performance characteristics of the prospective Australian shale plays' type-wells are not currently well understood due to lack of data. Significant exploration and appraisal activity is needed to augment the extremely limited shale gas well performance data available in Australia to date.