四川盆地二叠统海相碳酸盐岩储层测井评价

四川盆地下二叠统碳酸盐岩是目前重点勘探目标。与上二叠统礁滩相碳酸盐岩、下二叠统茅口组不整合面岩溶缝洞、热液白云岩不同,茅口组高能滩储层类型更加复杂化。对比分析几类储层特征基础上,针对礁滩相储层不同储集类型、不同孔隙区间以及不同储渗条件,建立了孔隙度和饱和度计算方法;针对茅口组高能滩相储层,剖析沉积微相变化、岩石矿物组分与灰泥储层构造对应关系,利用测井信息描述储集空间类型和分布特征,构建多元矿物体积模型逐点求取岩石混合骨架值,进而计算储层矿物组分和孔隙度,提高了灰泥储层参数计算精度。经岩心实验及试气验证,应用效果较好,具有良好的应用前景。

Log Evaluation of Permian Marine Carbonate Reservoir in Sichuan Basin

The Lower Permian carbonate reservoirs in Sichuan Basin is the key exploration target. Unlike the reef carbonate of upper Permian,unconformity cave-cleft bodies and hydrothermal dolomite of lower Permian Maokou Formation,the reservoir type of high-energy beach in the Maokou Formation is more complicated.Based on the comparison and analysis of several reservoir characteristics,the calculation methods of porosity and saturation are established according to different reservoir types,different pore intervals and different conditions of permeability in reef reservoirs.In view of the Maokou Formation high-energy beach facies reservoir,the changes of sedimentary microfacies and the relationship between rock mineral composition and structure of"calcilutite"reservoir are analyzed.T hen the pore space types and distribution characteristics of reservoir are described by logging information, the multiple mineral volume model was constructed to calculate the mixed rock matrix values point by point.Furthermore,the mineral composition and porosity of the reservoir are calculated.T herefore,the"calcilutite"reservoir parameter calculation precision is improved.T he method has good application effect according to the core test and gas test and show s a good application prospect.