泥页岩储层脆性评价实验研究——以贵州岑巩地区下寒武统牛蹄塘组泥页岩为例

Experimental Research on Brittleness Evaluation of Shale Reservoir ——By the Example of Shale Reservoir of the Lower Cambrian Niutitang Formation in the Cengong Region, Guizhou

泥页岩的压裂改造效果很大程度上由其脆性决定,开展泥页岩的脆性评价实验研究,可为页岩气田的开发与增产提供技术支撑。贵州岑巩地区下寒武统牛蹄塘组泥页岩层系内页岩发育良好,矿物组份复杂,非均质性强。通过对TX1井岩芯样品分别展开全岩矿物X-射线衍射、地层条件下的三轴压缩应力实验以及物性测定实验,系统分析矿物组成和岩石力学特征,并以实验结果为基础分析矿物成分与岩石物理参数的关系,明确了目的区域常规物性普遍较差,总体具有低孔-超低渗特征。该实验测试数据及取得的认识为该地区泥页岩层段的脆性评价研究能够提供一定指导。

The fracturing effect of shale is largely determined by its brittleness. Experimental research on brittleness evaluation of shale can provide technical support for shale gas field development and production increase. Shale is well developed in the Lower Cambrian Niutitang Formation in Cengong region, Guizhou, with complex mineral components and strong heterogeneity. In order to understand the brittleness of the reservoir, the X-ray diffraction of whole rock, triaxial compression stress experiments under formation conditions and physical property measurement experiments are carried out on core samples from well TX1. The mineral composition and rock mechanical characteristics are systematically analyzed. The relationship between mineral composition and rock physical parameters are analyzed based on the experimental results. It was confirmed that the conventional physical properties in the target are generally poor with low porosity and ultra-low permeability.