快速孔渗核磁共振测井模式设计

Designing a NMR Logging Model for Fast Estimation of Porosity and Permeability

为增强现有核磁共振测井仪器的纵向分辨率、提高测井速度,在常规CPMG测量序列的基础上,提出改进型FCPMG序列。对该序列的理论分析和工程软件建模仿真得出,在2 MHz的核磁共振岩心分析系统上进行测试实验,结果与理论仿真完全吻合。首次提出采用该序列高分辨率快速测量孔渗模型。通过饱和水的岩心测试分析,得出孔隙模式下,该测量模式能够快速测量,获得高精度、高纵向分辨率的测量结果。

An updated FCPMG sequence is proposed on the basis of the conventional CPMG sequence,which can enhance the vertical resolution of a NMR logging tool and increase logging speed.Theoretical analysis is fully consistent with software-modeled simulation through 2 MHz experiments on a nuclear magnetic core system.Meanwhile,proposes a fast and high-resolution model of porosity and permeability using this improved sequence for the first time.Tests on water-saturated cores have proved porosity and permeability can be obtained with high precision and high vertical resolution using the model.