TY  - JOUR
A1  - Pina-Valdes, Jesus
A1  - Socquet, Anne
A1  - Cotton, Fabrice
A1  - Specht, Sebastian
T1  - Spatiotemporal Variations of Ground Motion in Northern Chile before and after the 2014 M-w 8.1 Iquique Megathrust Event
T2  - Bulletin of the Seismological Society of America
N2  - To evaluate the spatiotemporal variations of ground motions in northern Chile, we built a high-quality rock seismic acceleration database and an interface earthquakes catalog. Two ground-motion prediction equation (GMPE) models for subduction zones have been tested and validated for the area. They were then used as backbone models to describe the time-space variations of earthquake frequency content (Fourier and response spectra). Consistent with previous studies of large subduction earthquakes, moderate interface earthquakes in northern Chile show an increase of the high-frequency energy released with depth. A regional variability of earthquake frequency content is also observed, which may be related to a lateral segmentation of the mechanical properties of the subduction interface. Finally, interface earthquakes show a temporal evolution of their frequency content in the earthquake sequence associated with the 2014 Iquique M-w 8.1 megathrust earthquake. Surprisingly, the change does not occur with the mainshock but is associated with an 8 month slow slip preceding the megathrust. Electronic Supplement: Strong-motion database.
Y1  - 2018
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/53203
SN  - 0037-1106
SN  - 1943-3573
VL  - 108
IS  - 2
SP  - 801
EP  - 814
PB  - Seismological Society of America
CY  - Albany
ER  -