Keywords:
Hochschulschrift
;
Costa Rica
;
Erdbeben
;
Seismotektonik
Description / Table of Contents:
The Central Pacific area of Costa Rica is a convergent erosional margin, characterized by a high seismicity rate, coincident with the subduction of rough-relief ocean floor. It has generated earthquakes with magnitude up to seven in the past along the subduction megathrust and the inner-forearc faulting. This study uses the records from a temporal seismological network, consisting of on- and offshore stations, installed for a period of six months in this segment of the Middle American margin. The aim was to obtain a model of the 3-D velocity structure of the margin and to characterize the seismicity of the shallow part (〈 70 km depth) of the subduction zone, with the focus on the seismogenic zone. A subset of well locatable events was selected to calculate a minimum 1-D model for the P-wave velocity. This model served as initial reference model for the subsequent 3-D inversion in a Local Earthquake Tomography, performed by inverting P- and S-wave traveltimes from 595 selected earthquakes. Several tools for resolution assessment were applied. Additionally, first-motion, double-couple focal mechanisms were determined for earthquakes originated at the plate interface, the subducting slab and the overriding plate. The results reflect the complexity associated to subduction of ocean-floor morphology and the transition from normal to thickened subducting oceanic crust...
Type of Medium:
Online Resource
Pages:
Online-Ressource (173 S.)
URL:
http://macau.uni-kiel.de/receive/dissertation_diss_00003072
URN:
urn:nbn:de:gbv:8-diss-30728
DDC:
551.220287097286
Language:
English
Note:
Kiel, Univ., Diss., 2008
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