海拉尔盆地南屯组凝灰质砂岩储层含水饱和度计算方法

Computational Method of Saturation of the Tuffaceous Sandstones Reservoir of Nantun Group in Hailar Basin

针对海拉尔盆地南屯组储层普遍含有凝灰质,且储层物性变化大等特点,对凝灰质砂岩储层建立凝灰质砂岩体积模型。利用放射性铀测井曲线确定凝灰质含量以达到与泥质含量的区别,计算出岩石的储层参数。将计算得出的孔隙度与岩心分析的孔隙度进行对比,可以得出孔隙度的绝对误差为1.51 p.u.,相对误差为10.16%。对同一区块多口井的南屯组凝灰质砂岩进行解释并且与试油资料进行分析对比,计算出的含水饱和度与实际试油的对比显示出很好的一致性。结果表明,建立的凝灰质砂岩解释模型与处理方法提高了储层描述的准确性,可以为该类凝灰质砂岩储层提供可靠的测井解释结果与储层参数,在海拉尔地区南屯组一段该类储层中的应用取得了很好的效果。

The tuffaceous sandstone volume model needs to be established as the Nantun reservoir of Hailar Basin generally contains tuffaceous sandstones and the reservoir physical properties vary in different blocks.The difference between tuffaceous content and shaliness makes it possible to distinguish the shale content while uranium log curve is used to confirm tuffaceous content,and then calculate reservoir parameters of rocks.From comparison between the calculated porosity and core-analysed porosity,we obtained that the absolute error of the porosity is 1.51 p.u.,and relative error is 10.16%.Log data of some wells with tuffaceous sandstones in the same block are processed and interpreted as well as compared with oil test data.The consistency between the calculated reservoir saturation and the oil test result is better.The results of log data processing and explanation for tuffaceous sandstone reservoirs in a number of wells as well as the analysis comparison with testing data show that this model has better application effect.