TA HVSR Curves and Peak Frequencies

Earthquake ground motions are modified by local geologic site conditions. Soft soils and basin sediments may amplify and prolong the duration of ground shaking, necessitating site characterization to improve existing ground motion predictions and seismic hazard analyses. Horizontal-to-Vertical Spectral Ratio (HVSR) measurements distinguish one or more site resonant frequencies and the relative amount of amplification at those frequencies with minimal cost and ground-disturbance. HVSRs are evaluated using either recordings of earthquake strong motions or hours of continuous microtremor data. Here, we provide microtremor HVSR (mHVSR) measurements at 2,194 sites across the continental United States acquired during the USArray Transportable Array experiment to support the creation and assessment of seismic velocity profiles and subsurface structure.