Publication Date:
2024-05-09
Description:
A systematic analysis is made of static Coulomb stress changes and
earthquake occurrence in the area of the North Aegean Sea, Greece, in order to assess the
prospect of using static stress changes to construct a regional earthquake likelihood
model.
Description:
A systematic analysis is made of static Coulomb stress changes and
earthquake occurrence in the area of the North Aegean Sea, Greece, in order to assess the
prospect of using static stress changes to construct a regional earthquake likelihood
model. The earthquake data set comprises all events of magnitude M ≥ 5.2 which have
occurred since 1964. This is compared to the evolving stress field due to constant tectonic
loading and perturbations due to coseismic slip associated with major earthquakes (M ≥
6.4) over the same period. The stress was resolved for sixteen fault orientation classes,
covering the observed focal mechanisms of all earthquakes in the region. Analysis using
error diagrams shows that earthquake occurrence is better correlated with the constant
tectonic loading component of the stress field than with the total stress field changes since
1964, and that little, if any, information on earthquake occurrence is lost if only the
maximum of the tectonic loading over the fault orientation classes is considered.
Moreover, the information on earthquake occurrence is actually increased by taking the
maximum of the evolving stress field since 1964, and of its coseismic–slip component,
over the fault orientation classes. The maximum, over fault orientation classes, of linear
combinations of the tectonic loading and the evolving stress field is insignificantly better
correlated with earthquake occurrence than the maximum of the tectonic loading by itself.
A composite stress–change variable is constructed from ordering of the maximum
tectonic loading component and the maximum coseismic–slip component, in order to
optimize the correlation with earthquake occurrence. The results indicate that it would be
difficult to construct a time–varying earthquake likelihood model from the evolving stress
field that is more informative than a time–invariant model based on the constant tectonic
loading.
Description:
This research was supported by the Foundation for
Research, Science and Technology under contract CO5X0402. Geophysics Department,
AUTH, contribution number 741.
Description:
Published
Description:
1049–1066
Description:
6T. Studi di pericolosità sismica e da maremoto
Description:
JCR Journal
Description:
open
Keywords:
Earthquake prediction
;
static stress changes
;
Greece
;
01. Atmosphere::01.02. Ionosphere::01.02.03. Forecasts
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
