Technology and Application of Fine Description for Complex Fault-Block Thin-Interbedded Condensate Gas Reservoirs

N gas field - typical complex fault-block thin-interbedded oil-ring condensate gas reservoirs. Due to the long development time of gas field, many problems like the low geological research level, the increasing complexity of structure, reservoir and fluid distribution need to be solved urgently. In order to effectively promote the recovery of production capacity as soon as possible and improve the development level of gas field, in view of the problems existing in the N gas field, such as the low quality of seismic data, the difficulty in identifying small faults as well as thin layers, and the difficulty in predicting reservoirs, the technology of fine description for complex fault-block thin-interbedded gas reservoirs was formed through comprehensive study. On the basis of ensuring the reliability of the seismic data, the Lumina spectral restoration technology was used to improve the resolution of the seismic data, and at the same time, fault detection technology in the multi-scale frequency domain was used to identify small faults and microstructures. After re-studying the underground structural characteristics of the gas reservoirs, the seismic control model and geo-statistics were combined to obtain a high-resolution lithology inversion data volume, which provided a reliable basis for the fine description of the reservoirs. Finally, the comprehensive quantitative evaluation technology of thin-interbedded reservoirs based on multi-parameter combination analysis was used to refine the evaluation of reservoirs to the level of single sand layer, and to divide four types of favorable reservoirs in N gas field, which provide the technical support for the adjustment of gas field development plans. Significant results have been obtained after the application of the technological achievements. Natural gas production in the N gas field increased steadily. 18 new wells were deployed in the Lower Talang Akar Formation, of which 8 were drilled and 5 were put into production, with an average initial production of 1,160 equivalent barrels per day. The workover measures were implemented for 30 wells with the average increased production of 265 equivalent barrels per day, which greatly increased the economic benefit reserves, extended the stable production period of the N gas field for more than 2 years.