In the heart of South China lies a treasure trove of energy waiting to be unlocked: coalbed methane (CBM). This abundant resource, tucked within numerous, thin coal seams, could significantly bolster China’s energy landscape. However, harnessing it effectively has proven challenging. A recent study published in Meitian dizhi yu kantan, translated to ‘Modern Geology and Prospecting’, sheds light on the geological intricacies and technological advancements needed to accelerate CBM development in the region.
Tao Guo, lead author of the study and a researcher at the Key Laboratory of Deep Coalbed Methane Exploration and Development, SINOPEC, emphasizes the unique characteristics of South China’s CBM resources. “The coal seams here are numerous and thin, with a considerable cumulative thickness,” Guo explains. “They exhibit moderate to high thermal maturity, high gas content, and complex tectonic conditions.” These features present both opportunities and hurdles for exploration and production.
The journey of CBM exploration in South China has evolved through three distinct stages. Initially, from 1989 to 2009, efforts focused on resource surveys and technological references. The subsequent decade saw technological exploration, while the current phase, starting in 2021, is about tackling deep CBM challenges and upgrading technologies.
One of the key strategies proposed by Guo and his team involves intensifying seismic exploration efforts. “We need to select optimal tectonically stable areas and conduct production capacity construction while assessing,” Guo advises. This approach, combined with rolling production based on well groups, could enhance the efficiency and effectiveness of CBM extraction.
Another significant recommendation is the implementation of large-scale commingled production of multiple coal seams. By optimizing pay zone combinations, operators can maximize the output from these thin, superimposed seams. Additionally, the study suggests adopting multistage fracturing of horizontal wells for dominant coal seams, a technique that could significantly boost production rates.
The exploration and production of deep CBM resources are also a focal point. Guo stresses the need to advance the exploration assessment of these resources, highlighting the potential for large-scale CBM production in South China. “Significant pathways include taking advantage of multiple coal seams, implementing reservoir stimulation through fracturing with fractures effectively propped, and accelerating geological assessment and target area selection of deep CBM resources,” Guo notes.
The commercial implications of this research are substantial. As China seeks to diversify its energy mix and reduce reliance on traditional fossil fuels, CBM offers a viable alternative. The successful development of South China’s CBM resources could lead to increased energy security, economic growth, and environmental benefits. Moreover, the technological advancements and strategies proposed in this study could have broader applications in other regions with similar geological characteristics.
The study’s findings are poised to shape future developments in the CBM industry. By providing a comprehensive understanding of the geological characteristics and technological requirements, it paves the way for more effective exploration and production strategies. As the energy sector continues to evolve, the insights from this research could play a crucial role in unlocking the full potential of South China’s CBM resources.
