Intense seismic activity in the South Euboean Gulf It was recorded in the early morning of September 9, 2025, according to a statement by the Interdisciplinary Risk and Crisis Management Committee of the NCSR. The Seismology laboratory of the Department of Geology and Geoopervalos closely monitors developments, under the direction of Professor George Kaviris.

To 00:27:58 (Greek time)seismic vibration of local size Ml = 5.3 It was marked 41 kilometers northeast of Athens, with the focus being located in the maritime area between South Euboean and the bay of the pedals. The focal depth is estimated at 13 km. The vibration was immediately felt in Attica and Southern Euboeawith the highest tensions being recorded in the area of ​​Agia Marina – Marathon and in Nea Styra, where they reached up to i = V at European long -standing scale (EMS). In Athens the tension is estimated as i = iv.

Assessment and Monitoring: Authorities’ reactions

OR Permanent Special Scientific Committee for OASP Seismic Risk Assessment He met extraordinary hours after the event. It was estimated that the earthquake came from an area of ​​moderate seismicity without particularly historical previous ones. Due to the geographical proximity to Attica, the vibration became very noticeable. Few aftershocks have been recorded so far and are likely to continue. The Commission declares ready -made a new meeting if citizens are required to be informed by official sources (OASP, Ministry of Climate Crisis and Civil Protection) on anti -seismic protection issues.

It is worth noting that, according to the data so far, the potential of crowning of the area It is limited, while the energy released seems to be the main event.

Earthquake characteristics and seismic mechanism

According to his first analyzes Laboratory and other scientific structures, the genesis mechanism indicates side-cannon burglary, with an estimated seismic torque size MW = 5.1-5.4. There are two dominant scenarios for the level of the rift, most likely to be in the NW-Directing Rift, in agreement with existing local geological data.

Geological history confirms that the wider area of ​​South Evia is characterized by small to moderate seismicity, with few important episodes recorded in recent years. Exceptions are seismic flocks in the neighboring area of ​​Polypotamos (2022-2023), as well as individual earthquakes in Psachna and Marcata.

Post -seismic activity and historical evidence

Prior to the main earthquake, at least three smaller ones were preceded by 10:30 am. On the same day there were 13 aftershocks ml≥2.0, the largest of which ml = 2.8. By historical data (Makropoulos et al., 2012), there are no significant seismic events in size over 4.0 over the last 120 years, which demonstrates the low seismic risk.

About 6 minutes after the earthquake, the Section of Geophysical-Genery Sector of the NCSR has recorded a record of traffic, with 18,179 unique visitors in just one minute, demonstrating the public’s strong interest in valid information on issues seismicity.

“The potential of the cracks in the Southern Euboean Gulf region, where the earthquake of 9 September 2025 occurred, is not particularly high. Therefore, unless there is immigration of Edigers, the earthquake ML = 5.3 that occurred was, with the main possibility, the main earthquake. “

For more information and scientific data visit:

  • EKEsology Laboratory – Seismic Event 9/9/2025
  • Euro-Mediterranean Seismological Center
  • Interdisciplinary Risk and Crisis Management Committee