Subsurface fracture characterization based on radar polarimetry by borehole radar

摘要

A fully polarimetric borehole radar system, using four antenna combinations of dipole and slot antennas, was developed to acquire fully polarimetric dataset. In this paper, we applied a polarimetric target decomposition method, Eigenvector-based decomposition, to a fully polarimetric borehole radar dataset for parameterizing subsurface fractures. Three important feature parameters Entropy, Alpha and Anisotropy could be extracted through this way. By comprehensively analyzing above three parameters, the important radar polarimetry analysis can be provided for main fractures, and then they can be well classified. Moreover, we find that the fracture classification result on basis of Eigenvector-based radar polarimetric analysis shows consistency with the result by using a polarimetric energy matrix method. We show potential of the polarimetric target decomposition techniques to fractures characterization.