  The location of El Ejido town over a deep sedimentary basin in a zone of high
seismicity in the Spanish context has motivated research on its seismic
response characterization. To this aim, S-wave velocity models have been
obtained from joint inversion of Rayleigh wave dispersion curves and
full-wavefield modelling of the horizontal-to-vertical spectral ratio of
ambient noise (HVSR) under the diffuse field assumption (DFA). Combination of
spatial autocorrelation surveys (SPAC) with array apertures of several hundred
metres and HVSRs displaying low-frequency peaks allowed to characterize deep
ground features down to the Triassic bedrock. Predominant periods in the town
ranged from 0.8 to 2.3 s, growing towards the SE, with few secondary peaks at
higher frequencies. The shallow structure has been explored by means of
geotechnical surveys, Multichannel Analysis of Surface Waves (MASW) and SPAC
analysis in small-aperture arrays. Resulting models support a general
classification of the ground as stiff soil.
