Publication Date:
2017-04-04
Description:
The southern portion ofthe Upper Rhine Graben, a major oblique rift among France, Germany and Switzerland, shows a weak
instrumental seismic record despite its remarkable physiographic imprint within the Northern Alpine foreland. Since traces of active
deformation can be found in this region and based on experience in other European areas with high seismic hazard and dense
population, we searched for past earthquakes recorded in historical catalogues. Based on the fact that tectonic deformation
cumulates through geological time and considering that long-term effects tend to leave characteristic signatures on present-day
landscape arrangement, our goal was to identify faults that could have caused the damage of recorded historical events.
We isolated five main earthquakes, ofmoderate Richter magnitude, essentially located on the E flank of the graben (as is the case
with recent seismic activity). To such events, we were able to associate a specific prospective structure through the use ofa procedure
thus far successfully employed in Southern European contexts. We concentrated on three events which showed (a) notable sensitivity
to the density of the historical felt reports and (b) accordance with on-going subtle deformation pattern. Another, most relevant
earthquake (M 5.5) yielded a promising match with the known deformation network in the region.
As a template to better constrain earthquake cycle and damage potential, historical seismicity offers an invaluable tool, since it
contains a specific record, although not always unambiguous. Cross-checking such data with pertinent geological information
allows to devise a realistic fault geometry capable of being responsible for a specific seismic event.
Description:
Published
Description:
403-425
Description:
open
Keywords:
historical seismicity
;
seismogenic sources
;
Upper Rhine Graben
;
04. Solid Earth::04.06. Seismology::04.06.05. Historical seismology
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
Format:
2729224 bytes
Format:
application/pdf
