基于Robust的AMT阻抗张量估计算法参数影响研究

摘要

Acrodding of AMT date in YunNan province polymetallic mine,influence on characteristic of Robust method are studied.The curves of apparent resistivity and phase cause coherency weighted and resistivity varience weighting estimation are discussed.The data is clearly been much better after take Robust method:the high frequency of apparent resistivity of data is obvious alleviation after Coherent estimate,much smooth and less jumppoints in low frequency of phase curve.choose rho-resistivity estimate better while more jump-points in low frequency,improve the degree of phase curve smooth,make middle-low frequency data deviation small,less flypoints.In any case,the data was much stable when taking Robust method.The results showed that Robust method could restrain the gaussian noise of AMT data,smooth the curve,make the high frequencies more closer to the actual geological conditions.%针对云南省澜沧多金属矿区AMT实测数据开展Robust阻抗估算的参数影响研究,挑选两个实测点数据进行相干因子估算和电阻率离差估算,得到其视电阻率和相位曲线图,分别对其进行讨论.经过Robust阻抗估算法处理过后的数据可以明显看出,只进行相干因子估算处理后数据其视电阻率高频段部分有明显的缓和,走势更平滑,在相位低频段部分跳点减少,数据得到改善;而当数据低频段跳点较多时只进行电阻率离差估算处理的效果更好,其相位曲线圆滑程度改善,中低频段数据离差小,数据稳定,飞点减少.研究结果表明,Robust阻抗估算法可以有效抑制非高斯噪声的AMT实测数据,平滑曲线,使高频段更接近实际地质情况.