中文摘要：

针对改良式CPMG（Car-Purcel-Meiboom-Gill）序列测量储层岩石内部磁场梯度分布时难以确定第一个窗口持续时间t0及回波个数NE1的问题,在总结T2-G实验采集参数人工调节规律的基础上提出t0、NE1的一项自动匹配技术：构造待测岩石的T2-G近似分布模型,基于该模型变化t0、NE1进行T2-G回波串正演数值模拟,结合T2-G最优化采集参数的约束条件确定t0、NE1。该技术在保证实验精度的前提下显著提高了实验效率,不同区块8块砂岩的T2-G实验结果也验证了该技术的可行性和实用性。

英文摘要：

In order to solve the difficulties in determining the acquisition parameters such as t0 and NE1when using the modified CPMG（ Car-Purcel-Meiboom-Gill） sequence to measure the internal magnetic field gradient of formation rock,an automatic matching technology for determining t0 and NE1was proposed after summarizing the empirical rules applied in the field：the T2-G approximated distribution model of tested rocks is first constructed; then with the approximated model the response of T2-G experiment is calculated by tuning t0 and NE1using numerical simulation methods,and lastly the suitable t0 and NE1are determined by using constraints from the optimal model. The accuracy and efficiency of the method is further verified in the T2-G experiment using eight sandstone samples from different regions.