Resource Potential for Co-Exploration and Joint Exploitation on Unconventional Gas in Coal Measures in China

China has considerable coal resources. Benefiting from the widespread distribution of coal measures and the inter-sedimentary development of coal bed, dark shale, and fine-grained tight sandstone in coal measures, China has a geological environment and material basis favorable for the co-occurrence of a variety of coal gases. With such a huge reservoir of coal gases, including gases such as coal bed methane (CBM), shale gas, tight sandstone gas, and natural gas hydrate, the co-occurrence of two or three of these gases is very common across the country. The per-well production of any individual coal measure gas (e.g., CBM) is generally low when exploited separately. Therefore, it is essential to have more gas explored and produced in one well to raise the per-well production, lower the cost, and thus, increase the economic benefit. Additionally, regarding gas control and treatment, coal measure gas, including CBM and surrounding rock gas (a major source of CBM), should be preliminarily pumped, to significantly reduce the number of coal mine gas accidents and effectively reduce greenhouse gas emissions. More extensive research and further exploration will result in the discovery of more coal measures containing multiple gases, increasing the proven resources of coal measure gas and substantiating the co-exploration and joint exploitation of coal bed gas in China.