Site characterization and site response in Port-au-Prince, Haiti
Waveform analysis of aftershocks of the Mw7.0 Haiti earthquake of 12 January 2010 reveals amplification of ground motions at sites within the Cul de Sac valley in which Port-au-Prince is situated. Relative to ground motions recorded at a hard-rock reference site, peak acceleration values are amplified by a factor of approximately 1.8 at sites on low-lying Mio-Pliocene deposits in central Port-au-Prince and by a factor of approximately 2.5–3 on a steep foothill ridge in the southern Port-au-Prince metropolitan region. The observed amplitude, predominant periods, variability, and polarization of amplification are consistent with predicted topographic amplification by a steep, narrow ridge. A swath of unusually high damage in this region corresponds with the extent of the ridge where high weak-motion amplifications are observed. We use ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) imagery to map local geomorphology, including characterization of both near-surface and of small-scale topographic structures that correspond to zones of inferred amplification.
Citation Information
Publication Year | 2011 |
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Title | Site characterization and site response in Port-au-Prince, Haiti |
DOI | 10.1193/1.3637947 |
Authors | Susan E. Hough, Alan K. Yong, Jean Robert Altidor, Dieuseul Anglade, Douglas D. Given, Saint-Louis Mildor |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Earthquake Spectra |
Index ID | 70101105 |
Record Source | USGS Publications Warehouse |
USGS Organization | Earthquake Science Center |