库车坳陷迪北气藏致密砂岩储层“甜点”预测

“Sweet Spot” Prediction of Tight Sandstone in Dibei Gas Pool

迪北气藏位于库车坳陷东部,其储集层为侏罗系阿合组致密储层,该气藏具有致密砂岩气的特征,又有构造控产的特点,所以将其定义为复杂碎屑岩低渗致密凝析气藏.而对于迪北气藏致密储层的“甜点”预测受山前地震资料限制,一直难以取得有效进展.分析总结了迪北气藏天然气富集规律和控产因素,并借鉴前人经验在该区首次利用“多相带逐级刻画”对致密储层“甜点”分级刻画.研究成果与各井产能分布情况吻合度较高,并能够直观有效地预测气藏储层“甜点”,对于指导本区井位部署和勘探开发具有重要意义.

The Dibei natural gas field is located in the eastern Kuqa depression,and the main reservoir is the Jurassic Ahe formation. The gas pool is featured by both the tight sandstone gas and the structural deformation,i.e.,the complex clastic low-permeability tight condensed gas pool. The prediction of"sweet spot"have been restricted by the seismic data quality. In this research,the controlling factors of hydrocarbon accumulation and production were summarized,and the"multi-phase integrated matching"method was used to investigate the grading of"sweet spot". Results have shown that the predictions were in highly accordance with well drillings,which could be used as guidance for the future hydrocarbon prospecting.