SEISMICITY of the KOPETDAG REGION in 2018–2019

Abstract

In 2018–2019, the monitoring of seismicity in the Kopetdag region was carried out by a network of 34 seismic stations of the Institute of Seismology and Atmospheric Physics of the Academy of Sciences of Turkmenistan, of which 20 are stationary and 14 are mobile. For two years, 348 earthquakes with KR≥8.6 were registered, for 62 events the focal mechanisms were determined. More than 20 earthquakes were felt in the settlements of Turkmenistan, but only a part of them were localized directly within its borders. The earthquake of January 7, 2018 with KR=12.1 (mb=4.8), located in the Balkhan-Caspian area, was felt with maximum intensity on the territory of Turkmenistan and caused shaking in the city of Turkmenbashi with an intensity of Ii=3–4, and in the city of Balkanabat Ii=2–3. Among seismic events outside Turkmenistan, the earthquakes that occurred in Afghanistan on May 9, 2018 (Mw=6.3) and December 20, 2019 (Mw=6.2) stand out with the highest magnitude and macroseismic manifestations in the territory of Turkmenistan. The shaking intensity from the first event in the nearest settlements of Tajikistan and Afghanistan was Ii=5, and in the Turkmen city of Magdanly (483 km) – Ii=2–3. The second event was felt in Dushanbe (Tadjikistan) up to Ii=4, and in Magdanly (Turkmenistan, =418 km) – up to Ii=2. Among the seismically active areas of the Kopetdag region, the maximum amount of seismic energy in 2018 was released on the territory of the Turkmen-Khorasan area, and in 2019 – in Eastern Turkmenistan. For the Kopetdag region as a whole, seismic activity and corresponding parameters of the seismic regime in 2018 and 2019 decreased significantly compared to their long-term averages.