Investigation of attenuation of the Lg-wave amplitude in the Caribbean region
Abstract
The focus of this study is to determine the frequency-dependent quality factor function Q (f) for the Caribbean region. The analysis considers the Lg portion of 2685 three-component waveforms. Waveforms are selected from 116 earthquakes that occurred between 2006 and 2013 with moment magnitude Mw ranging from 4.6 to 7.0. Spectral amplitudes over 12 distinct passbands from 0.1 to 12.8 Hz are calculated only for waveforms with a signal-to-noise ratio of 5 or better. In the regression model, the vertical component and the geometric mean of two horizontal components are used to estimate Q (f). A geometrical spreading function with spectral amplitude decay of R−0.5 is used for distances beyond 100 km. The following quality factor functions for the assumed geometrical spreading are obtained: QH = 310f0.54 for the horizontal components, and QV = 235f0.65 for the vertical components.
Publication Title
Bulletin of the Seismological Society of America
Recommended Citation
Hosseini, M., Pezeshk, S., Haji-Soltani, A., & Chapman, M. (2015). Investigation of attenuation of the Lg-wave amplitude in the Caribbean region. Bulletin of the Seismological Society of America, 105 (2), 734-744. https://doi.org/10.1785/0120140006
