Identification of Basin Topography Characteristic Using Multivariate Singular Spectrum Analysis: Case Study of the Taipei Basin: Fid-Bau Portal

Identification of Basin Topography Characteristic Using Multivariate Singular Spectrum Analysis: Case Study of the Taipei Basin

Chang, Yu-Wen / Van Bang, Phung / Loh, Chin-Hsiung

Abstract

Abstract The effects of earthquake-induced basin amplification are caused by the interaction of wave-fields with a basin boundary, which depend on complex source to site distances, basin geometry (topography), and sediment distribution within the basin. In this study the identification of long-period waves induced by strong earthquake motions through basin topography together with local site effects of the basin is investigated. Through multivariate singular spectrum analysis (MSSA), a unique analysis tool for extracting tendencies and harmonic components in geophysical time series is used to extract the long-period wave of basin response caused by the seismic events. Seismic response data of Taipei Basin were used to examine the existing of the lowest dominant frequency of the basin caused by basin topography. Finally, the seismic-induced ground motion data can be separated to local site effects and the basin motion caused by the effect of topography.

Highlights • Multivariate singular spectrum analysis was used to extract long period seismic waves. • Basin topology effect was identified from the basin earthquake response data. • Site response in the basin includes both the local site effect and the topography effect. • Seismic response data of the Taipei Basin were used to examine the topography effect. • Topography effect cannot be ignored for design of structures in the basin.