3D near-surface soil response from H/V ambient-noise ratios

• Published in: Soil dynamics and earthquake engineering (1984) Vol. 22; no. 9; pp. 865 - 876
• Main Authors: Woolery, Edward W., Street, Ron
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Oxford Elsevier Ltd 01-10-2002; Elsevier Science
• Subjects: Ambient-noise; Earth sciences; Earth, ocean, space; Earthquakes, seismology; Exact sciences and technology; Internal geophysics; Site effects; New Madrid region; United States; Ambient-noise; Site effects; interfaces; velocity structure; stratigraphic columns; topography; S-waves; earthquakes; North America; seismic surveys; seismic response; amplitude; three-dimensional models; soil profiles; noise; soils; site effects; sediments; seismic waves
• ISSN: 0267-7261; 1879-341X
• DOI: 10.1016/S0267-7261(02)00109-4

The applicability of the horizontal-to-vertical (H/V) ambient-noise spectral ratio for characterizing earthquake site effects caused by near-surface topography and velocity structures was evaluated at sites underlain by thick (i.e. >100
m) sediment deposits near the southern-end of the New Madrid seismic zone in the central United States. Three-component ambient-noise and velocity models derived from seismic (shear-wave) refraction/reflection surveys showed that a relatively horizontal, sharp shear-wave velocity interface in the soil column resulted in an H/V spectral ratio with a single well-defined peak. Observations at sites with more than one sharp shear-wave velocity contrast and horizontally arranged soil layers resulted in at least two well-defined H/V spectral ratio peaks. Furthermore, at sites where there were sharp shear-wave velocity contrasts in nonhorizontal, near-surface soil layers, the H/V spectra exhibited a broad-bandwidth, relatively low-amplitude signal instead of a single well-defined peak.