 |
| Titel |
Source model resolution of the 2010 Haiti earthquake - What can we learn by combining geodetic, seismologic and geologic data? |
| VerfasserIn |
Henriette Sudhaus, Frank Krüger, Thomas R. Walter |
| Konferenz |
EGU General Assembly 2011
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 13 (2011) |
| Datensatznummer |
250053957
|
|
|
|
|
|
| Zusammenfassung |
| On 12 January 2010 a devastating earthquake occurred on the Hispaniola Island in the
vicinity of the Haitian capital Port-au-Prince. The earthquake epicenter is located close to the
Enriquillo-Plantain Garden Fault (EPGF), a major left-lateral strike-slip fault that has
a very clear topographic surface expression. On the basis of ground movement
measurements from GPS (Global Positioning System) a large earthquake with a typical
strike-slip source mechanism had been anticipated for this fault years before the
disaster.
Source complexities already emerged with the first data analyses, however. Firstly, the
Centroid moment tensor solutions showed a strong thrust component and a significant
portion of non-double-couple, this may point to a higher rupture complexity than
expected for this earthquake. Secondly, studies that analyzed the coseismic surface
deformation measured by using InSAR (Interferometric Synthetic Aperture Radar) and
GPS resulted in very different fault slip models. What all source models seem to
agree on is that a considerable part of the seismic energy was not released on a
segment of the EPGF itself but on a northward dipping thrust fault slightly north of
it.
An outstanding question is, however, whether the limited data availability can
result in any number of similarly-likely source solutions. Problems are that in Haiti
the local geology and fault systems are complex, as expressed in the variety of
geologic/tectonic maps, and that they are only partly exposed on-land. The latter fact also
hampers geodetic observation of crustal deformation in the co-seismically affected
area. Furthermore, the seismic recordings of the Haiti earthquake are limited to
far-field observations. The absence of directly observed surface ruptures for the
2010 Haiti earthquake adds further to the uncertainties in source model estimation
here.
We here suggest a combined optimization of the data sets under consideration of the
individual data errors. We attempt to estimate the extent to which data errors and
gaps influence the outcome of the Haiti earthquake source modelling. Such model
uncertainty estimations will provide important additional information to the single
source models and form an improved basis for evaluations of seismic hazard in
Haiti. |
|
|
|
|
|
|