Gas Content Measurement and its Relevance to Outbursting

The use of core and alternatives to its use for gas content measurement of coal is examined. The measurement of gas content from cuttings is presented in two forms, one involving the recovery of cuttings with air drilling and the second involving the collection of all released gas from the hole during overbalanced drilling. The latter approach is suitable for not only coal but all gas bearing formations including siltstones and sandstones, provided they do not have major open pore space such as vugs. The paper also deals with the importance to outbursting of gas content, broken coal particle size and diffusion coefficient.