Earthquakes on Santorini decrease: Volcanic activity returns to normal level.
Current Earthquake Situation in Santorini
The seismic activity affecting Santorini and surrounding islands has shown a gradual decline since mid-February 2025, although experts predict tremors may continue for weeks or possibly months.
The earthquakes began on 26 January, with over 23,500 recorded events thus far, primarily concentrated southwest of Anydros.
Key Statistics and Observations:
- Daily frequency of earthquakes: Decreasing
- Maximum magnitude: Reducing (highest recorded was 5.3 magnitude)
- Epicentre location: Consistent (no significant shifts)
- Microseismic surges: None recorded since 15 February
The University of Athens’s Interdisciplinary Risk Management Committee confirms the epicentral area remains stable, suggesting a potential stabilisation of underlying geological processes. The earthquake swarm’s gradual decline has encouraged many residents to return to the island.
Population Impact
The residents of Santorini are slowly returning to their homes as the intensity and number of earthquakes appear to be decreasing.
According to official figures from the Independent Department of Civil Defence of the Municipality of Thira and information from Fraport and the Port Authority of Thira, 5,475 residents returned to the island between 12 and 26 February.
According to ERT, the number of inhabitants remaining on the island on 11 February was estimated at 4,000. 11,000 of Santorini’s 15,000 inhabitants had fled.
Despite the reduced frequency of tremors, Professor Efthymios Lekkas, head of the Earthquake Planning and Protection Organization, cautions that this seismic sequence may continue for several weeks or even months, as “this type of seismic activity does not subside easily.”
Geological Assessment
Seismologists have attributed the tremors to natural tectonic processes and magma movements beneath the seabed.
However, experts have discounted concerns about potential eruptions from:
- Nea Kamini volcano (on an islet off the main island)
- Underwater volcano Kolumbo
- Formation of new volcanic structures
Despite these reassurances about volcanic activity, landslides remain a significant concern, particularly on Santorini’s iconic cliffs where homes, businesses, and hotels are perched. Mayor Nikos Zorzos has requested additional government assistance for rockfall control and hillslope fencing repair.
Ongoing Safety Measures
The undersea shocks—sometimes occurring just minutes apart—prompted authorities to implement several safety protocols:
- School closures across multiple islands
- Various movement restrictions
- Plans for a special evacuation port
- Temporary suspension of cruise ship visits
While the earthquakes have caused only minor structural damage and no reported injuries thus far, monitoring continues. Some researchers suggest the seismic events might indicate expansion of the island’s volcanic complex, as noted by seismologist Costas Synolakis.
The tourism industry, vital to Santorini’s economy, watches these developments closely. The island, once rated the world’s most popular tourist destination, typically generates most of its revenue during the spring and summer months.
As the earthquake activity diminishes, tourism operators anticipate a gradual return to normal operations, though continued monitoring of both seismic activity and cliff stability remains essential.
Schools to Reopen on Santorini on Tuesday
After nearly a month of closure, schools on Santorini and surrounding Cycladic islands will resume operations on Tuesday, 4th March 2025. This decision follows significant reduction in seismic activity that had prompted authorities to suspend educational activities throughout February.
The reopening comes after thorough evaluation by the Seismic and Volcanic Risk Committees, which confirmed that earthquake sequences in the maritime area of Anydros between Thira and Amorgos have substantially decreased.
Over the past fortnight, seismic events have maintained consistently low levels, creating suitable conditions for resuming normal educational activities.
Building Safety Assessment
School buildings across the affected islands have demonstrated remarkable resilience during the seismic events. Official inspections have revealed:
Building Type |
Condition |
Safety Status |
|---|---|---|
School facilities |
No structural damage |
Safe for occupation |
Public buildings |
Minor cosmetic issues |
Fully operational |
Infrastructure |
Stable |
Passed inspection |
Engineering teams have certified that educational facilities withstood the seismic loading effectively. The robust construction standards employed throughout the Cyclades have proven their worth during this extended period of geological instability.
Safety Protocols to Remain in Place
Despite the favourable assessment, authorities emphasise that safety measures must continue.
School administrators have been instructed to maintain earthquake preparedness protocols as the risk, whilst significantly diminished, has not completely disappeared.
Recommended safety measures include:
- Regular earthquake drills to be conducted weekly
- Emergency evacuation routes to be clearly marked and kept obstruction-free
- Classroom furniture secured appropriately to prevent tipping
- Emergency supplies maintained in accessible locations
- Staff training on emergency response procedures to continue
The Education Ministry has distributed updated safety guidelines to all school administrators, with particular emphasis on maintaining calm and orderly procedures should any further seismic events occur.
Community Response
The decline in seismic activity has brought significant relief to Santorini residents.
Local authorities report that more than 5,500 people who temporarily left the island during the height of the earthquake swarm have now returned. This number represents approximately 60% of those who sought safer locations during the period of heightened activity.
With schools reopening, officials anticipate a substantial influx of returning families. The municipal government has established welcome centres to assist families transitioning back to normal life on the island.
“The community’s resilience has been extraordinary,” noted a civil protection official. “From maintaining essential services to supporting vulnerable populations, Santorini has demonstrated exemplary community spirit throughout this challenging period.”
Educational Continuity Plans
To address the academic disruption caused by the month-long closure, education authorities have implemented a comprehensive catch-up strategy:
- Extended school hours in the initial weeks
- Adjusted curriculum focusing on essential learning outcomes
- Additional support for examination-year students
- Online resources to supplement classroom instruction
- Flexibility in assessment deadlines
Teachers have been participating in preparatory sessions since Wednesday, ensuring smooth transition when pupils return to classrooms. Special attention will be given to addressing any anxiety or stress students may feel about returning to school buildings.
Monitoring Systems Remain Active
Video from the ‘classroom’ in the earthquake simulator of the Natural History Museum in Heraklion::
While schools reopen, scientific monitoring of the region continues unabated.
The Hellenic Seismic Network maintains enhanced surveillance of the Anydros basin area with:
- Continuous real-time seismic monitoring
- Regular scientific committee assessments
- Daily public updates on seismic activity levels
- Rapid response protocols should activity increase
These monitoring efforts provide additional reassurance to parents and educators that any significant changes in seismic patterns would be promptly detected and appropriate measures implemented.
Economic Implications
The reopening of schools signals a positive step toward normalcy for the island’s economy, which relies heavily on tourism.
Local business owners express relief that the situation is stabilising before the peak tourist season.
The Chamber of Commerce reports that hotel bookings for April and May, initially affected by news of the seismic activity, have begun to recover. This positive trend coincides with the return of residents and resumption of regular community activities.
Tourism operators emphasise that visitor safety remains the primary concern, with enhanced emergency protocols now integrated into standard operating procedures across accommodation and activity providers.
Long-term Preparedness
The experience has prompted authorities to enhance long-term earthquake preparedness across the Cyclades. New initiatives include:
- Expanded public education on seismic safety
- Structural assessment programmes for older buildings
- Integration of advanced seismic monitoring technology
- Community-based emergency response teams
- Regular multi-agency emergency simulations
What Does Tselentis Say About Santorini’s Earthquake Risks?
Renowned seismologist Akis Tselentis has expressed significant concerns regarding earthquake safety measures on Santorini, particularly criticising what he describes as a superficial approach to structural inspections.
The expert has been quite vocal about the unlawful construction practices around the caldera area, which he believes pose substantial risks.
Tselentis has characterised recent government efforts as mere public relations exercises rather than substantive safety measures. He argues that bringing rescue dogs, emergency responders, and medical staff to the island fails to address the fundamental issue: illegal structures along the caldera that have not undergone proper structural assessment.
Critical Safety Concerns
The seismologist has outlined several key concerns:
- Inadequate Structural Inspections: Only visual assessments have been conducted, which Tselentis describes as preliminary measures inadequate for ensuring safety
- Lack of Follow-up Actions: Property owners have not been required to improve foundational supports where feasible
- School Safety Questions: Schools reopened based on cursory visual inspections without detailed structural analyses
- Caldera Construction Risks: Particularly dangerous structures exist along the caldera rim
“Treating significant problems with aspirin-like solutions solves nothing,” Tselentis metaphorically states regarding the superficial nature of current safety assessments.
School Safety Protocols
Tselentis has expressed particular concern about the decision to reopen Santorini schools. According to him, authorities made this determination based solely on observing a decline in seismic activity, suggesting it was time to “return to normality.” He argues this approach is dangerously simplistic.
The seismologist recommends:
- Only schools initially deemed safe should resume operations
- A detailed inspection programme should be implemented over subsequent months
- Specific methodologies for structural assessment must be employed
- Targeted reinforcement of school buildings should follow assessments
He notes that school administrators have received nothing beyond initial visual inspection reports—a situation he finds deeply troubling.
Tourism and Economic Considerations
Despite his concerns, Tselentis offers reassurance about most areas of Santorini. He repeatedly states that the island, excluding the caldera region, remains safe even for earthquakes measuring up to 6.0 on the Richter scale. This assessment supports the resumption of normal tourism activities for the upcoming season.
The expert acknowledges the caldera’s significance as a tourist attraction, but insists that actions must be taken to reduce seismic risk in this area. His concerns about dangerous constructions along the caldera have been echoed by ministry services, adding credibility to his warnings.
While this does not mean that we should expect disasters even in the event of an earthquake measuring 6 on the Richter scale, the warning systems for a possible tsunami must continue to operate, especially during the period when the beaches are full of tourists, and the risk of landslides on unstable slopes must be minimised immediately.
Historical Context and Current Risk Assessment
Tselentis draws important parallels with previous seismic events, noting that pre-earthquake activity in Arkalochori and other regions continued for many months. This historical perspective informs his cautious approach to Santorini’s current situation.
He advises:
Risk Level |
Area |
Safety Assessment |
|---|---|---|
Low |
Most of Santorini |
Safe even for 6.0 magnitude events |
High |
Caldera edge |
Requires immediate structural assessments |
Variable |
School buildings |
Needs comprehensive evaluation programme |
The seismologist stresses that whilst catastrophic damage isn’t expected even from a 6.0 magnitude earthquake, maintaining tsunami warning systems is essential, particularly for coastal areas.
Tselentis has expressed hope that a 6.0-magnitude earthquake might actually help release accumulated energy, potentially stabilising the region. However, he cautions against complacency, believing the public should maintain a degree of vigilance rather than being lulled into a false sense of security.
Scientific Monitoring and Preparation
The ongoing seismic tremors between Santorini and neighbouring islands have raised concerns about the Kolumbo submarine volcano. While earthquake intensity has declined somewhat, Tselentis urges continued caution as seismic activity persists.
Since August 2024, the volcano has shown activity signs, causing measurable shifts in the earth. Despite these changes, experts including Tselentis maintain that an eruption isn’t necessarily imminent, though all scenarios remain possible.
Tselentis has resigned from Greece’s earthquake risk assessment board, citing political interference in scientific matters. This context adds weight to his independent evaluations and critiques of the current approach to Santorini’s safety measures.
Expert Bohnhoff warns of 50 per cent probability of a volcanic eruption
In the Frankfurter Rundschau, the German earthquake expert Marco Bohnhoff for geomechanics and scientific drilling at the German Research Centre for Geosciences (GFZ) warns of a possible volcanic eruption.
We have only seen the symptoms near Santorini about half a dozen times since records of earthquakes began – and in half of the cases this led to a volcanic eruption.
A volcanic eruption could result in a tsunami up to 40 metres high.
Commonly Asked Questions
Earthquakes Updates in the Aegean
Recent earthquakes in the Aegean
Advice for Tourists During an Earthquake in Santorini
Tourists are advised to stay calm and seek open spaces if outside, or take cover under sturdy furniture indoors during an earthquake.
Following instructions from local authorities and emergency services is crucial for safety.
Information from the Greek Civil Protection for earthquakes (in English)
Has seismic activity around Santorini reduced lately?
Yes, recent reports indicate that earthquake activity near Santorini has begun to diminish. According to Greece’s chief seismologist, the frequency of earthquakes affecting Santorini has eased in recent days. However, experts caution that the outlook remains uncertain, and the region could experience continued tremors in the coming weeks.
How often do earthquakes occur in the Santorini region?
The Santorini area regularly experiences seismic activity due to its volcanic nature. Since 24 January 2025, there has been an accumulation of weak to moderate earthquakes recorded around the island. This activity has been concentrated between Santorini and Amorgos, with the epicentre approximately 25 km north-east of Santorini.
Is Santorini situated on active tectonic plate boundaries?
Yes, Santorini is located in a seismically active region. The island sits within the Hellenic Arc, which is part of the complex boundary where the African tectonic plate is subducting beneath the Eurasian plate. This tectonic setting contributes to both the volcanic nature of Santorini and its susceptibility to earthquakes.
What are the current developments regarding Santorini’s earthquakes?
As of late February 2025, the seismic sequence continues but with decreasing intensity.
The earthquakes have prompted some adjustments in the tourism industry. For example, cruise lines are rerouting to alternative ports and tour operators are providing reassurances about safety.
Greek authorities have implemented emergency measures, and scientists from research centres such as GEOMAR and GFZ are actively monitoring the situation.
The earthquakes are occurring at depths between 4 and 10 kilometres. Experts continue to analyse the data to better understand the nature of this seismic sequence.
