Enriching Factors of Carboniferous Gas in Tiandong Region, East Sichuan

Key words: 
• East Sichuan (Chuandong) /
• Carboniferous /
• gas /
• enrichment factors

Abstract: The Tiandong gas region is of a rich ore discovered in East Sichuan (Chuandong) since recent years, that has a good accumulative condition, high productivity, not wholly controlled by structural trap for gas enrichment. Through research,it is discovered that gas enrichment is mainly controlled by Kaijiang-Liangping paleo-uplift. Which has formed not only a series of composite trap of stratigraphy and structure, and also promoted the still more development of the effective thickness and pores of Carboniferous reservoir resulting in better accumulative condition on the basis of Carboniferous sedimentation factes and diagenesis of this region, beneficial to the development of pores. Secondly, it is situated within the low synclinores between two high and steep anticlines of Datianchi and Nanmenchang; the structural position is low.,and the trap is mostly adjacent to broad syncline which has not only the performance of preferentially accumulating the upmigrating gas from the underlying Silurian gas-origin layer, but also has a large area of controlling oil and gas enrichment,abundant gas-source, and high filling degree for the trap. Lastly, the paper has concisely commented the gas-bearing conditions of various traps.