Today, 23.11.2022, an earthquake of magnitude Mw6.1 occurred in northwestern Türkiye at 01:08 UTC. The epicentre was located near the city of Düzce, about 210 kilometres east of the metropolitan area of Istanbul with its more than 16 million inhabitants. The earthquake was felt in both Istanbul and Ankara (source: BBC online).
Today's earthquake is of moderate magnitude and has occurred in the upper 10 kilometres of the Earths’ crust along the North Anatolian Fault Zone. There, the Anatolian tectonic plate moves westward at about 2.5 centimetres per year relative to the Eurasian plate. Friction in the Earth's crust prevents the plates from sliding continuously, causing accumulation of elastic energy which is then released at irregular intervals in the form of earthquakes.
Marco Bohnhoff, GFZ earthquake expert for the region:
"The area of the M6.1 earthquake was already activated in 1999 by two strong earthquakes with magnitudes of 7.4 (Izmit/Kocaeli) and 7.1 (Düzce). Earthquakes in this region are of particular importan"e because further west below the Sea of Marmara offshore of Istanbul there is a so-called 'seismic gap' along which an earthquake with a magnitude of up to 7.4 can be expected in the future. In case of such an earthquake, tens of thousands of fatalities and hundreds of thousands of homeless people as well as massive damage to infrastructure can be expected," says Marco Bohnhoff, head of the Section "Geomechanics and Scientific Drilling" and earthquake expert of the GFZ German Research Centre for Geosciences for this region.
On the mechanism of the quake
The mechanism of today's earthquake is a right-lateral, so-called strike-slip displacement and corresponds to the known tectonic deformation pattern of the region. During the quake, the two Earth plates moved horizontally past each other, releasing some of the energy built up by the plate movement. "This is remarkable, because this area can actually be considered 'seismically discharged' since the 1999 events and the loading process towards a next strong earthquake is just underway at this location," says Bohnhoff. In all likelihood, this earthquake has no influence on the seismic gap off Istanbul today.
Figure and GEOFON link: