Tuzla earthquake swarm in Turkey


Komut T., Baysal R.

ACTA GEOPHYSICA, vol.70, no.3, pp.1037-1045, 2022 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 70 Issue: 3
  • Publication Date: 2022
  • Doi Number: 10.1007/s11600-022-00784-w
  • Journal Name: ACTA GEOPHYSICA
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1037-1045
  • Keywords: Earthquake swarm, 2017 Tuzla (Ayvacik) earthquake activity, Earthquake clustering, ANATOLIAN FAULT ZONE, STRAIN-RATE FIELD, BIGA PENINSULA, WESTERN ANATOLIA, MARMARA REGION, AEGEAN SEA, SEISMICITY
  • Çanakkale Onsekiz Mart University Affiliated: Yes

Abstract

Long-lasting earthquake clusters are common in western Anatolia. One of them has been active in the southwestern part of the Biga peninsula. We had studied this cluster in terms of strain energy produced over time and revealed its interesting characteristics. The seismicity in this clustering region is not normal in terms of both the number of earthquakes, duration of the activity, magnitude/frequency and mainshock/aftershock relations, and the strain energy produced. An abnormal seismic activity with a set of medium-sized earthquakes without a mainshock, which are indistinguishable in size occurred in this clustering region in 2017. Interesting features that are characteristic of earthquake swarms are probably related to the abnormal physical properties of the crust. The 2017 Tuzla activity, where there is also no notable aftershock activity, could be associated with a phase of the swarming phenomenon itself. For this, we approached the 2017 activity in terms of the fact that it may not be part of the active tectonic system. Apart from the presence of high geotherm and hot springs in the region, the crust has been weakened by pre-existing intense fault zones that have developed in previous deformation regimes since the paleo-tectonic periods. Historical and instrumental period large earthquakes have caused loss of life and property in Biga peninsula due to an existing active fault zone. The Tuzla region probably is in this zone extending NE-SW in the peninsula. However, it is very difficult or impossible to distinguish possible foreshocks or precursory phenomenon of a future large earthquake from the background activity of the earthquake swarms.