The 2022 MW 6.0 Gölyaka-Düzce earthquake: an example of a medium size
earthquake in a fault zone early in its seismic cycle
Abstract
On November 23rd 2022, a MW 6.0 earthquake occurred in direct vicinity
of the MW 7.1 Düzce earthquake that ruptured a portion of the North
Anatolian Fault in 1999. The Mw 6.0 event was attributed to a small
fault portion of the Karadere segment that did not rupture during the
1999 sequence. We analyze the spatio-temporal evolution of the MW 6.0
Gölyaka-Düzce seismic sequence at various scales and resolve the source
properties of the mainshock. Modelling the decade-long evolution of
background seismicity of the Karadere Fault employing an Epistemic Type
Aftershock Sequence model shows that this fault was almost seismically
inactive before 1999, while a progressive increase in seismic activity
is observed from 2000 onwards. A newly generated high-resolution
seismicity catalog from 1 month before the mainshock until six days
after created using Artificial Intelligence-aided techniques shows only
few events occurring within the rupture area within the previous month,
no spatio-temporal localization process and a lack of immediate
foreshocks preceding the rupture. The aftershock hypocenter distribution
suggests the activation of both the Karadere fault which ruptured in
this earthquake as well as the Düzce fault that ruptured in 1999. First
results on source parameters and the duration of the first P-wave pulse
from the mainshock suggest that the mainshock propagated eastwards in
agreement with predictions from a bimaterial interface model. The MW 6.0
Gölyaka-Düzce represents a good example of an earthquake rupture with
damaging potential within a fault zone that is in a relatively early
stage of the seismic cycle.