The "Telegraph" newspaper wrote that Istanbul, Turkey, is facing a major earthquake risk, stating that the city's dense population, old buildings, and location on the North Anatolian Fault increase the danger.
Modern.az reports that the publication noted Istanbul, with a population of nearly 15 million, is one of the cities in the world with the highest risk of a large-scale disaster due to an earthquake.
The article emphasizes that Istanbul's geographical structure also increases the danger. Densely built buildings on the city's steep slopes, narrow streets, and multi-story residential buildings hastily constructed in the late 19th century are listed among the main factors posing a risk during an earthquake.
The city is located around the Bosphorus Strait, which separates the European and Asian parts. The North Anatolian Fault passes through northern Turkey and extends under the Sea of Marmara.
The "Telegraph" writes that strong earthquakes occur in Istanbul approximately every 250 years. The last major earthquake in the city is noted to have occurred in 1766.
The 1999 earthquake near Izmit caused the death of more than 17,000 people. In April 2025, a 6.2 magnitude earthquake in the Sea of Marmara injured more than 230 people in Istanbul.
According to the publication, seismologists at the time stated that the Marmara fault was activated and energy was being released in stages.
The article notes that strict building standards are applied in cities with high earthquake risk, such as Tokyo. Turkey also tightened building regulations after the 1999 earthquake.
However, the Kahramanmaraş earthquake in February 2023 revealed the serious consequences of non-compliance with building codes. As a result of the disaster, more than 62,000 people died, more than 100,000 people were injured, approximately 280,000 buildings were completely destroyed, and another 700,000 buildings were damaged.
The "Telegraph" states that Istanbul's old housing stock is also a serious problem. It is emphasized that old and densely packed buildings, especially in the city center, pose a great danger during a strong earthquake.
The article notes that the characteristics of the North Anatolian Fault also increase the risk. Earthquakes on this fault sometimes occur not only as a single strong tremor but as a series of successive smaller earthquakes.
After the earthquake in the Sea of Marmara in 2025, at least 272 aftershocks were recorded within 24 hours, the strongest of which reached 5.9 magnitude. Such tremors also complicate rescue efforts under the rubble and increase the risk of damaged buildings collapsing again.
Experts and insurance companies consider a possible earthquake in Istanbul to be one of the world's most severe scenarios. Tehran and Manila are also listed among high-risk cities.
According to a study conducted by the GFZ Helmholtz Centre for Geological Sciences in 2025, the probability of a strong earthquake occurring in Istanbul within the next 30 years is estimated to be between 35-47 percent.
According to the latest calculations by 12 leading seismologists, since 1766, the "displacement deficit" along the fault under the Sea of Marmara has reached approximately 6 meters. This indicator shows that significant tectonic stress has accumulated in the area for more than two centuries.
