19–23 Jun 2023
Hofburg Palace & Online
Europe/Vienna timezone

Seismicity and Tectonics of the Caucasus Region Revisited

20 Jun 2023, 11:00


Board: 7
E-poster T1.2 The Solid Earth and its Structure Lightning talks: P1.2-2


Istvan Bondar (Research Centre for Astronomy and Earth Sciences (ELKH))


The Caucasus region lacked a comprehensive catalog, despite its role in Arabia-Eurasia convergence between the Black and Caspian Seas. The Lawrence Livermore National Laboratory and the Institute of Earth Sciences (IES) at Ilia State University generated a new, comprehensive seismic catalog for the period from 1951 to 2019 for the Caucasus region by combining data in the IES bulletin with bulletins of the Republic Seismic Survey Center of Azerbaijan, monitoring centers in Turkey and Armenia, and the ISC.
We present ~20,000 newly relocated events in this bulletin. We relocated each event using the single-event location algorithm iLoc and regional seismic travel time predictions and identified GT events. We relocated the entire seismicity of the Caucasus region with the multiple-event location algorithm Bayesloc, using the iLoc results as initial locations and the GT events as constraints.
We show that each relocation step leads to significant improvements, as indicated by tightening of event clusters. The improved view of the seismicity reveals a narrow band of crustal events along the southern flank of the Greater Caucasus we interpret as a megathrust, and confirms both a region of deep seismicity beneath the northeastern Caucasus and a possible area of slab detachment in the central part of the range.

Promotional text

Strengthen the engagement of the scientific communities working in test-ban monitoring. As a result of the contribution of this large dataset, regional earth models will be improved, which will reduce the uncertainties in regional discrimination studies.

E-mail [email protected]

Primary author

Istvan Bondar (Research Centre for Astronomy and Earth Sciences (ELKH))


Mr Eric Cowgill (University of California Davis (UC Davis)) Dr Tea Godoladze (Ilia State University) Gurban Yetirmishli (Republic Seismic Survey Center of Azerbaijan National Academy of Sciences) Mr Stephen Myers (Lawrence Livermore National Laboratory (LLNL)) Ms Tuna Onur (Seemann Consulting, Inc., Victoria, British Columbia, Canada) Ms Rengin Gok (U. S. Department of Energy, National Nuclear Security Administration) Andrea Chiang (Lawrence Livermore National Laboratory (LLNL))

Presentation materials