Determination of S-wave velocities for shallow structures in the Potiguar Basin using passive seismic interferometry
Passive seismic; Passive Seismic Interferometry; Surface Wave; Dispesion curve; Inversion.
Passive seismic interferometry has proven to be a tool for obtaining subsurface information on a crustal, regional, and local scale. This tool is used in the present work to determine velocity model parameters in the Potiguar Basin, using ambient seismic noise data obtained by surface sensors during two hydraulic fracturing operations. The minimum and maximum distance between sensors in this experiment are 10 and 1,500 m, respectively. The ambient seismic noise records are processed to obtain correlograms containing the empirical Green's Function between the different sensor pairs used in the experiment. With these correlograms, we obtain dispersion curves that allow us to estimate the subsurface S-wave velocity values using a 1D Earth model. These 1D S-wave velocity profiles are the basis for the characterization of the shallow sediment layers of the Potiguar basin in the region studied. The cost-effectiveness of passive seismic interferometry allows us to consider this method a viable option for exploratory projects with low economic and environmental costs. Additionally, the method can help improve the resolution of shallower structures from seismic surveys with active seismic.