随机岩溶介质的电阻率正演模拟

Forward modeling of resistivity in random karst medium

受岩溶发育的影响,岩溶地区电阻率分布具有很大的不确定性。采用传统的正演方法在一定程度上不能满足岩溶探测的需要。为了更真实地反映岩溶介质的电性特点,本文提出了一种根据随机过程的谱分解理论来构造随机介质模型的方法,并以此建立了岩溶地区随机地电模型。对理论和实测地电模型的正演计算表明,随机介质能更有效模拟实际地电结构,正演结果更接近实测的异常形态。因此,岩溶地区的电阻率正演模拟计算采用随机介质模型是十分有必要的,一方面有助于对异常的认识,另一方面,随机介质模型可以更好地模拟岩溶地区的地电模型。

The distribution of electrical resistivity in karst area is of great uncertainty,due to the complex of underground karst features.Sometimes,the traditional forward modeling methods can not meet the needs of karst detection.In order to truly describe the electrical characteristics of karst media,a method to construct random medium model based on spectral factorization theory of stochastic process was proposed in this paper,and some stochastic geoelectric models in karst area were established.The forward theoretical calculation and measured geoelectric models showed that the random medium model could simulate the actual geoelectric structure more effectively,and the forward modeling results were closer to the measured abnormal character.Therefore,it is necessary to use the random medium model in forward modeling of resistivity in karst area.On one hand,it helps to understand the anomality,on the other hand,the random medium can better simulate the geoelectric phenomenon in karst area.