基于全区视电阻率瞬变电磁一维正演中滤波系数的选取

Selection of Filter Coefficient in One-dimensional Forward of Transient Electromagnetic Method Based on All-time Apparent Resisivity

为提高瞬变电磁正反演数值计算的效果和效率,选取合适的数值滤波系数是关键。通过建立参照模型,选用正演数值计算效果良好的3组汉克尔变换滤波系数和3组余弦变换滤波系数,对比分析了其不同组合正演的计算效率、精度和有效范围。利用瞬变响应的平移伸缩特性提出参数模型法,实现了针对实测数据的滤波系数选取的估算,经过反演测试,最终得出了基于全区视电阻率的最佳滤波系数组合。

In order to improve the effect and efficiency of numerical calculation of transient electromagnetic forward and inversion,it is the key to select an appropriate numerical filtering coefficient.By establishing a reference model,three groups of Hankel transform filter coefficients and three groups of cosine transform filter coefficients with good calculation results were selected to compare and analyze the calculation efficiency,accuracy and effective range of their different combination forward modeling.The reference model method which based on characteristic of translational expansion and contraction was proposed to estimate the filtering coefficient for measured data.Finally,the best filter coefficient combination based on all-time resisitivity was obtained through inversion test.