Site Response Characteristics of Simeulue Island, Indonesia as Inferred from H/V Spectral Ratio of Ambient Noise Records

Journal of Mathematical and Fundamental Sciences

卷:48

Nugroho Dwi Hananto¹  Lina Handayani¹  Titi Anggono²  Syuhada² 

[1] Research Center for Geotechnology, Indonesian Institute of Sciences, Jl. Cisitu Sangkuring, Bandung 40135;

[2] Research Center for Physics, Indonesian Institute of Sciences, Kawasan PUSPIPTEK Serpong, Tangerang 15310;

关键词: ambient noise;    amplification factor;    fundamental frequency;    H/V spectral ratio;    site response;    Simeulue Island;   

DOI  :  10.5614/j.math.fund.sci.2015.48.2.4

来源: DOAJ

【 摘 要 】

Simeulue Island is an outer island arc west of Sumatra Island. The island is located close to the interface of the subduction zone between the Indo-Australian and Eurasian plates. Seismic activities around the island include devastating megathrust earthquakes, such as the 2004 MW 9.2 Sumatra-Andaman and 2005 MW 8.7 Nias earthquakes. We have investigated site response characteristics using the Horizontal-to-Vertical (H/V) Spectral Ratio method based on continuous ambient noise records from eight broadband seismometers. From the calculation results, generally, strong peaks were observed in the H/V spectral ratio curves caused by strong impedance contrast in this area. However, the BATU, LABU and DEHI sites showed relatively flat H/V spectral ratio curves caused by a lack of sharp impedance contrast beneath the site. Multiple peaks were observed at several sites, which may indicate the presence of a more highly weathered soil/clay layer on top of a more compact medium. H/V peak frequencies, which reveal the fundamental resonant frequencies of the soil sites, were generally observed in the range of 2.0 Hz-16.4 Hz.

【 授权许可】

Unknown