 |
| Titel |
Shallow and Deep Crustal Seismicity under the Precordilleran Belt, Northern Chile |
| VerfasserIn |
Joern Kummerow, Pablo Salazar, Peter Wigger, Serge A. Shapiro, Günter Asch |
| Konferenz |
EGU General Assembly 2010
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 12 (2010) |
| Datensatznummer |
250042859
|
|
|
|
|
|
| Zusammenfassung |
| We have analyzed crustal and Nazca slab- related seismicity around 21°S in Northern Chile,
which has been recorded by a temporary local seismic network in the years 2005-2009.
The focus of this study is the high-resolution location of more than 1000 crustal
earthquakes in the Precordilleran region with local magnitudes Ml in the range between
-0.5 < Ml < 5.4. We have applied a largely automized earthquake location algorithm,
which includes cluster identification and optimization of arrival times for events within each
cluster. Seismicity shows different patterns north and south of 21°S, respectively. It is
distributed along several distinct active segments of the West Fissure Fault System at
shallow depths (< 10km). A west-dipping major crustal interface, which has been
unrevealed before, can be clearly imaged from a few kilometers depth near the West
Fissure Fault system at 69°W down to about 25km depth. We have also detected two
deep crustal earthquake clusters (35 - 40km depth). Their position and orientation
correlate remarkably well with previously found bands of high seismic reflectivity,
supporting the interpretation as being images related to ongoing fluid migration. |
|
|
|
|
|
|