Impact of density information on Rayleigh surface wave inversion results

摘要: Abstract We assessed the impact of density on estimation inverted shear-wave velocity ( V s ) using multi-channel analysis surface waves (MASW) method. considered forward modeling theory, evaluated model sensitivity, and tested effect information inversion seismic data acquired in Arctic. Theoretical review, numerical modeled real indicated that ratios between layers, not actual values, determination surface-wave phase velocities. Application compared results using: a) constant density, most common approach practice, b) indirect estimates derived from refraction compressional-wave observations, c) direct measurements a borehole. The use reduced final typically by 6–7% densities borehole 10–11% to those assumed density. In addition improved absolute accuracy, resulting overall changes were unevenly distributed laterally when viewed 2-D section leading an structure was more representative subsurface environment. It observed instead increasing with depth only can lead overestimation but it also create inaccurate structures, such as low-velocity layer. Thus, optimal estimations be best achieved field ratios.