Two-dimensional joint inversion of DC resistivity method and seismic traveltime tomography method based on the FCM cluster constraint

Two-dimensional joint inversion of Direct Current resistivity method (DC) and first-arrival traveltime seismic tomography method have been studied in our paper, by adding the Fuzzy C-means clustering model (FCM) constraint function to inversion cost function in order to constrain the resistivity and velocity. In the near surface geophysical exploration, conductivity geological bodies always have low seismic speed, whereas resistivity geological bodies usually have high seismic wave speed. The DC resistivity method is sensitive to conductivity bodies because this region attracts current, and seismic traveltime tomography method is sensitive to high-speed bodies because the rays are concentrated in the high-speed region. Therefore, the combination of two data sets can greatly improve the quality of inversion result. The synthetic examples showed that the joint inversion of DC resistivity method and first-arrival traveltime seismic tomography method improves the resolution ability for both resistivity and speed geological model, and complements each other. Particularly the joint inversion with FCM model constraint, in which supervised learning is carried out by using priori physical properties, further improves the quality of inverted models and the resolution of geological units.