Novokayakentskoe-I earthquake on August 26, 2025 in the shelf part of the Caspian Sea with ML=5.6

Instrumental and macroseismic data are presented on the earthquake on August 26, 2025 at 20:33 (UTC) with ML=5.6, h=78 km with the epicenter in the shelf part of the Caspian Sea. The earthquake parameters were determined based on instrumental data from the network of regional seismic stations of the North Caucasus of the GS RAS and the networks of the nearest surroundings. The focal mechanism solution was obtained based on the signs of the first arrival of P-waves at 95 seismic stations. It was found that the focal point was a normal fault along one of the nodal planes of steep dip and sublatitudinal strike. In tectonic terms, the earthquake under study occurred in the middle part of the Caspian Sea, where earthquakes of similar depth and mechanism had occurred before, for example, on April 22, 2000, 08:46 (UTC) with mb=5.1 (MOS). According to preliminary data, the earthquake was felt in Novokayakent, Makhachkala, Kaspiysk, Kizilyurt, Derbent, Izberbash, Dagestanskiye Ogni, Tarki, Kyakhulai with an intensity of 4–5 points, Samur – 4 points, Bavtugay, Khasavyurt – 3–4 points, Grozny, Gudermes – 3 points, Astrakhan – 2 points.