DYNAMIC CHARACTERISTICS ANALYSIS ON WUBAOCHANG STRUCTURE OF SHAXIMIAO FORMATION GAS RESERVOIRS AND SOME IDEAS ABOUT ITS EXPLOITATION AND PRODUCTION

The Shaximiao Formation gas reservoirs in the Wubaochang structure is a kind of shallow fluviolacustrine facies sandstone gas reservoirs, which was explored and developed as a whole for the first time in Northeast Sichuan Basin. In order to extract the gas reservoirs in scientific, reasonable, and high-efficient way, and provide reliable references for setting out a good plan on exploitation, the gas reservoirs performance should be analyzed, summarized and studied as well. Through studying on the monitoring data and the features on gas reservoirs from the initial recovery, it was found out that three wells in the Block Wubao Qian well 2-1 were interconnected with high connectivity, whereas the similar feature of which about the other wells in the other Blocks needed to be testified by later monitoring. In the Shaximiao Formation gas reservoirs, no formation water has been found, neither the movable water found while drilling so far. Natural gas in the gas reservoirs was thought to be a kind of good-quality nonassociated gas with less H2S and low-content CO2 discovered in the gas wells. Some suggestions on next-step exploitation were put forward in detail as follows: ①Reasonable and scientific rules and regulations during the production should be set down, the operation style of a gas well should be determined and the production capacity ought to be adjusted according to its actual production; ②The performance on the gas reservoirs should be under control by use of monitoring techniques on gas reservoirs; ③The normal production for the gas reservoirs should be ensured by regular analysis on production behaviors; ④After comprehensive study on the features of the Shaximiao Formation which are characterized by multiple sets of sand bodies and multiple gas-production layers in the vertical direction, well locations should be deployed on the favorable parts of the new formation in order to enhance the yield of the gas reservoirs.