SURFACE DISTRIBUTED ACOUSTIC SENSING (S-DAS) FOR HIGH RESOLUTION NEAR SURFACE CHARACTERIZATION. RESULTS FROM A 3D ONSHORE FIELD EXPERIMENT

Abstract

Distributed acoustic sensing (DAS) technology enables high-density seismic acquisition at a fraction of the cost. When deployed on the surface, surface distributed acoustic sensing (S-DAS) acquisition provides a cost-effective solution for dense high-resolution near surface characterization through the analysis and inversion of surface waves. This is made possible by the relatively low cost of the fiber and the dense spatial sampling of the realized seismic data. S-DAS data were collected during the acquisition of a 3D land large-scale field test and processed with a focus on recent advancements in the use of surface-wave analysis and inversion. We compare and validate the result from the S-DAS recording with co-located multicomponent (3C) geophones and a conventional high-density surface seismic nodal acquisition. The comparison to 3C geophones demonstrated that for applications such as surface wave inversion S-DAS can outperform conventional geophones and shows consistency between electrical resistivity tomography (ERT) and surface seismic inversion from S-DAS. Additionally, continuous passive recording of environmental noise also offers a convenient alternative to active shooting allowing the surface wave inversion from reconstructed virtual shots.