川西坳陷低渗致密砂岩气藏难采储量分类评价

SYSTEMATIC EVALUATION OF RESERVES DIFFICULT TO RECOVER OF TIGHT SANDSTONE GAS RESERVOIR IN THE DEPRESSION OF SICHUAN-WEST

川西地区难采储量蕴藏着较大的开发潜力,开展其储量评价对同类气藏的开发具有指导作用。川西地区难采储量多为低渗致密砂岩气藏,具有“低、小、散、差"的地质特点和“低、快、短、大”的开发特征。难采储量的主要影响因素有储层本身地质条件、工艺技术水平、经济环境以及企业管理模式、开发政策等客观条件,但随着开采工艺技术的完善和改进、经济政策的变化、管理模式的优化配置,部分难采储量可转化为可动用储量或经济储量,因此其又具有时间性和阶段性。本文针对川西地区难采储量的特殊性,从储层地质条件、储层改造、开采工艺水平、天然气开发政策、企业管理模式、气价以及开发成本等方面分类论述了难采储量开发的可行性和经济性,促进难采储量得到最大限度的开发。

Reserves difficult to recover in Sichuan-west region have great development potential,which the reserves evaluation can provide the supervision for exploitation of the uniformity gas reserves.The gas reserves of Jura in the depression of Sichuan-west belong to lake basin and deltaic deposit.The ore masses interlace one another in the vertical orientation and the phase tract change frequently in the plane.The reserves have the characteristics of densification.The exploitation dynamic characteristics include the low production and pressure,shortness of period of stabilized production,and smallness of controllable reserves.Furthermore,many reserves are difficult to recover,whose exploitation is confined by the completeness of development technique and the change of economic policy,as a result,it has the timeliness and phase character.In regarding to the exploitation characteristic of tight sandstone gas reserves of low permeability in the west region of Sichuan,the paper tells of the reserves estimate from the geology,movability as well as economic aspects of reserves which are difficult to recover.