Analysis of HVSR Data Using a Modified Centroid-Based Algorithm for Near-Surface Geological Reconstruction

Recently, the use of microtremor techniques for subsoil investigation has increased significantly. The HVSR (Horizontal to Vertical Spectral Ratio) technique allows, in many cases, obtain a seismo-stratigraphic reconstruction and identify areas with similar seismic behavior. However, stratigraphic interpretation peaks still remains subjective choice linked priori information. A non-hierarchical centroid-based algorithm was modified group different measurements that can be attributed same generating discontinuity. Some tests performed have shown proposed produces valid results even absence information evaluate optimal grouping. obtained acquired city Modica (Italy) are presented. cluster analysis these data on lithologies outcropping area made it possible reconstruct 3D model main discontinuities.