四川广安地区侏罗系凉高山组储层特征研究

广安地区碎屑岩油气藏是目前勘探开发的热点。通过岩心观察、薄片鉴定、X衍射分析、扫描电镜分析等手段,得出了区内凉高山组砂岩属于灰质胶结超低孔低渗极致密储层;区内成岩阶段划分为同生期、早成岩A—B期、中成岩A—B期;强烈持久的成岩作用导致储层致密化,其中强烈的机械压实作用减少砂岩的孔隙,碳酸盐矿物的胶结作用使孔隙度和渗透率显著减少。

The Jurassic Lianggaoshan Formation Reservoir in Guang'an,Sichuan

Oil and gas accumulation in Guang'an is a hot point of oil and gas exploration in Sichuan at present.Drilling core observation,rock section study,X-ray diffraction analysis and SEM observation indicate that the Lianggaoshan Formation is composed of dense calcareous sandstone with super-low porosity and super-low permeability.The diagenesis may be divided into syngenesis,eodiagenesis A-B and mesodiagenesis A-B stages.Long-term and intense diagenesis resulted in the compaction of the reservoir,especially,intense mechanical compaction led to the decrease in the porosity,while cementation of carbonate minerals obviously reduced the porosity and permeability.