Subsurface fine structures survey by GPR B-scan image based on signal subspace method

Ground Penetrating Radar (GPR) is an efficient remote sensing tool for geophysical subsurface survey. These structure characteristics are recorded in radar signal profiles by means of echo detection, amplitude and phase estimation. Besides the energy attenuation and absorption of GPR EM pulse during its propagating downward direction into the ground from a transmitting antenna, the strong interferences, clutters, multiples and random noise, often make the fine-structures hardly distinguishable. This paper develops a signal subspace method to detect fine fractures, leading to water intrusion at the Dazu Rock Carving site. With field surveying data, this method is validated to detect sub-surface fine structure with sparse representation and yields discriminative fracture signature for geological interpretation.