| Autor: |
Douilly, Roby, Mavroeidis, George P., Calais, Eric |
| Předmět: |
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| Zdroj: |
Geophysical Journal International; Oct2017, Vol. 211 Issue 1, p400-417, 18p |
| Abstrakt: |
The devastating 2010 Mw 7.0 Haiti earthquake demonstrated the need to improve mitigation and preparedness for future seismic events in the region. Previous studies have shown that the earthquake did not occur on the Enriquillo Fault, the main plate boundary fault running through the heavily populated Port-au-Prince region, but on the nearby and previously unknown transpressional Léogâne Fault. Slip on that fault has increased stresses on the segment of Enriquillo Fault to the ~3-million-inhabitant capital city of Port-au-Prince. In this study, we investigate ground shaking in the vicinity of Port-au-Prince, if a hypothetical rupture similar to the 2010 Haiti earthquake occurred on that segment of the Enriquillo Fault.We use a finite element method and assumptions on regional tectonic stress to simulate the low-frequency ground motion components using dynamic rupture propagation for a 52-km-long segment.We consider eight scenarios by varying parameters such as hypocentre location, initial shear stress and fault dip. The high-frequency ground motion components are simulated using the specific barrier model in the context of the stochastic modeling approach. The broad-band ground motion synthetics are subsequently obtained by combining the low-frequency components from the dynamic rupture simulation with the high-frequency components from the stochastic simulation using matched filtering at a crossover frequency of 1 Hz. Results show that rupture on a vertical Enriquillo Fault generates larger horizontal permanent displacements in Léogâne and Port-au-Prince than rupture on a south-dipping Enriquillo Fault. The mean horizontal peak ground acceleration (PGA), computed at several sites of interest throughout Port-au-Prince, has a value of~0.45 g, whereas the maximum horizontal PGA in Port-au-Prince is ~0.60 g. Even though we only consider a limited number of rupture scenarios, our results suggest more intense ground shaking for the city of Port-au-Prince than during the already very damaging 2010 Haiti earthquake. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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