Soil Amplification and Peak Frequencies from Thousands of Passive Seismic Measurements Across Metro Vancouver, British Columbia, Canada
Abstract
Seismic site effects arise from local geologic and topographic conditions, and modify incident earthquake ground motions at a site. Understanding variability in seismic site conditions is necessary for accurate assessment of seismic hazard. The microtremor horizontal to vertical spectral ratio (mHVSR) method is a cost-effective and non-invasive method to measure the site’s filtering effect in terms of an amplification frequency spectrum. Using a large, compiled database of mHVSR measurements from the Metropolitan Vancouver area, the impact of acquisition and processing parameter choices on the computed mHVSR is investigated. A robust processing algorithm is developed to batch process high-quantity mHVSR datasets. Products related to seismic microzonation hazard mapping, such as a regional map of the site fundamental frequency and the suite of unique mHVSR amplification spectra in the region are provided. This thesis exemplifies the practicality of using the mHVSR method for seismic site characterization.