Coalbed Methane System of Cretaceous Sahai Formation in Fuxin Basin

Key words: 
• coalbed methane system /
• Cretaceous /
• Sahai Formation /
• Fuxin Basin

Abstract: The investigation on the coalbed methane system is a guide to the exploration and development of coalbed methane. Using the theory and method of unconventional petroleum system, the Sahai Formation coalbed methane system was studied. The source and reservoir rock is the third coal seams of Sahai Formation. The Sahai Formation coalbed methane is sealed by the roof comprising mudstone and lutite of the fourth Sahai Formation. The overburden is the fourth Sahai Formation and Fuxin Formation deposits. The dolerite intrusion during the Himalayan orogeny enhanced the coal maturity and caused a peak of hydrocarbon generation. In addition, the underwater brought many bacteria generating second biogenic methane. Then the coalbed methane is reserved and a critical moment of the coalbed methane system is at the end of the Late Tertiary. In summary, the Sahai Formation coal seams are favorable for coalbed methane exploration and the Dongliang district will to be a promising area for coalbed methane exploration.