川西坳陷新场气田储集岩的地质特征

The geology of hydrocarbon reservoirs in the Xinchang gas field, West Sichuan depression

关键词:  川西坳陷  储集特征  新场气田

Key words:  West Sichuan depression  reservoir quality  Xinchang gas field

摘要:

四川盆地西部德阳市境内的新场气田,其纵向上分布有8个气藏,平面上相互叠置,是目前国内在致密砂岩中所发现的最大气田。笔者通过对新场气田砂岩储集岩的地质特征、成岩作用和储集条件的研究,气田的主要储集空间为次生的残余粒间孔和粒间溶孔,大部分砂岩的孔喉都能使天然气通过。天然气主要聚集在储集岩与围岩在物性上或孔隙结构上有较大差异的部位。因此,在勘探上,应该从单纯寻找高孔渗带转移到寻找物性差异带上来。

Abstract:

Eight gas pools are hosted in the Xinchang gas field in Deyang,western Sichuan,which is known as the largest gas field found in dense sandstones in China.The research on the geology, diagenesis and reservoir quality of the reservoir sandstones in the gas field has disclosed that secondary and residural intergranular spores and solution openings may serve as main pore spaces.The natural gas may pass through most of the pore throats of the sandstones,and tend to be accumulated commonly in the localities where there are large discrepancies physically or in pore types of the reservoir rocks.Therefore the emphasis on the future research should be shifted from the highly permeable zones to the physically different zones.