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Frequency-dependent attenuation of the Hispaniola Island region of the Caribbean Sea

D. McNamara·M. Meremonte·J.Z. Maharrey·S-L. Mildor·J.R. Altidore·D. Anglade·S. E. Hough·D. Given·H. Benz·L. Gee·A. Frankel
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Abstract

We determine frequency-dependent attenuation 1/Q( f ) for the Hispaniola region using direct S and Lg waves over five distinct passbands from 0.5 to 16 Hz. Data consist of 832 high-quality vertical and horizontal component waveforms recorded on short-period and broadband seismometers from the devastating 12 January 2010 M 7.0 Haiti earthquake and the rich sequence of aftershocks. For the distance range 250–700 km, we estimate an average frequency-dependent Q( f )=224(±27) f 0.64(±0.073) using horizontal components of motion and note that Q( f ) estimated with Lg at regional distances is very consistent across vertical and horizontal components. We also determine a Q( f )=142(±21) f 0.71(±0.11) for direct S waves at local distances, ≤100 km. The strong attenuation observed on both vertical and horizontal components of motion is consistent with expectations for a tectonically active region.

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D. McNamara, M. Meremonte, J.Z. Maharrey, S-L. Mildor, J.R. Altidore, D. Anglade, S. E. Hough, D. Given, H. Benz, L. Gee, A. Frankel. 2012-03-29. Frequency-dependent attenuation of the Hispaniola Island region of the Caribbean Sea. https://doi.org/10.1785/0120110137

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