Interrelationship Between Coalbed Methane (CBM) and Produced Ground Water in Lephalale Basin, South Africa

Abstract

Methane gas production from unconventional resources has gained increased prominence worldwide. In South Africa, prospective regions for Coalbed Methane (CBM) exploration are Ellisras (Lephalale) Basin, Springbok Flats Basin and the Amersfoort Coalfield in Ermelo. This research focuses on examining the petroleum system, water system and in developing a conceptual hydrogeological model to demonstrate the interdependency of Coalbed Methane and produced groundwater in Lephalale. The hydrochemical analysis approach was used to assess the water quality by detailed assessment of major constituents, total dissolved solids, dissolved gases and trace elements in produced ground water. Historical data was used in order to understand the factors controlling the gas incline and water decline production curves. Results and data from this research has contributed to a greater understanding of interrelationship between Coalbed Methane production rates and groundwater. Comparing these results with global trends in Coalbed Methane development indicates that the identified study area has great potential for Coalbed Methane. Economical production of Coalbed Methane in other coal bearing Karoo basins, requires an integrated study of the factors controlling accumulation of the gas, a detailed assessment of salinization levels and an understanding of technological and environmental difficulties encountered during gas production.

AAPG Datapages/Search and Discovery Article #90259 ©2016 AAPG Annual Convention and Exhibition, Calgary, Alberta, Canada, June 19-22, 2016