萤火虫算法在凝灰质砂岩储层测井解释中的应用

Application of glowworm swarm optimization algorithm in the log interpretation for tuffaceous sandstone reservoir

凝灰质砂岩储层的岩石成分和孔隙结构复杂,物性变化大,准确计算出各成分的体积分数,特别是凝灰质的含量,是提高这类储层测井解释精度的关键。在求解此类问题时,传统测井解释方法中的简单矿物模型及其方程组解法容易出现不稳定的解或不合理的解释结果。为此,提出了一种基于萤火虫算法的最优化测井解释方法,结合岩石体积物理模型,应用于海拉尔盆地凝灰质砂岩储层解释。在综合考虑各种误差与约束条件的情况下,计算出了凝灰质含量、孔隙度等储层参数。计算结果与岩心数据吻合度较好,说明萤火虫算法可行,最优化测井解释的结果可靠。

Since the rock composition and pore structure of tuffaceous sandstone reservoir is complex with great physical property variation, the key to improve the precision of log interpretation for such reservoir is to accurately calculate the vol- ume fraction of each component, especially the tuffaceous content. The simple mineral model and its equation set solution used in traditional log interpretation method are likely to generate unstable solution or unreasonable interpretation results during solving these problems. Combined with the rock bulk model, an optimal log interpretation method based on glowworm algo- rithm is proposed and applied to tuffaceous sandstone reservoir in Hailar Basin. By comprehensively considering various er- rors along with constraint conditions, tuffaceous content, porosity and other reservoir parameters are calculated. The calculat- ed results and core data are matched well, which indicates that glowworm algorithm is feasible and the results of optimal log interpretation are reliable.