Tsunami likely at time of earthquake

Geology Professor Şükrü Ersoy from Yıldız Technical University said Istanbul’s next big earthquake would create a tsunami based on historical findings of an excavation of Yenitepe. And according to Ersoy, because Istanbul’s coastlines are narrow, the tsunami waves are liable to cause serious damage to vehicle traffic and buildings in that corridor. "A wave one meter high may cause all the cars on the shore to drift into the sea and people to drown," Ersoy said.

Holes may be trigger

Ersoy said that the three great holes in the Marmara Sea were all going to trigger tsunamis. "In order for a tsunami to be formed by an earthquake, there needs to be a vertical movement on the seabed. If an earthquake occurs at the lateral movement fault lines, tsunamis may not be formed. There are fault lines in the Marmara Sea that may cause vertical movement. Under normal conditions, in order to cause a tsunami, the earthquake must be at least seven on the Richter scale. There are at least three holes at the Marmara Sea bottom that exceed 1,000 meters in depth. There is soft, unconsolidated mud that has been carried from the shore at the precipitous slopes of these holes. An earthquake registering six on the scale would not cause a tsunami but underwater avalanches could occur. The mud on the slopes of those holes may move to the bottom suddenly due to the underwater avalanches and this change at the bottom may cause tsunamis," said Ersoy.

"Deposits that show traces of previous tsunamis were dug at the excavations on the Marmara’s shores. There have been over 40 destructive tsunamis on the shores of Marmara. There are cases when the waves came on shore covering 2,000 to 3,000 meters with their height exceeding 6 meters. Those waves sometimes entered the Bosphorus and affected districts like Eyüp and Üsküdar alongside important valleys. The most affected areas on the Marmara shores are the Kapıdağ Peninsula, İzmit Bay, Istanbul, Thracian Shores, Mudania and Marmara Island," said Ersoy.

The facts that Istanbul’s topography is not straight and its shores are narrow are disadvantages when it comes to tsunamis, according to Ersoy, recalling that even small waves may be deadly on shores approximately 150 to 200 meters wide. "In the earthquake of 1894, the sea first ebbed by 50 meters than the returning sea waves destroyed the whole Ottoman navy on shore. Dozens of boats sunk by the tsunami have been found at the excavation of Yenikapı, which was a port in ancient times. If a disaster has happened in the past, it means it will happen again in the future," he said. Ersoy said the efforts to strengthen the structures of schools were insufficient and criticized the process. "The number of schools that are set to be strengthened by 2010 is 505. The largest share of foreign aid to strengthen and rebuild state buildings is saved for schools with $144 million. There are 1,783 schools in Istanbul that were inspected in terms of durability but only 598 of them are to be strengthened or rebuilt. Other aid is needed for dealing with the remaining schools," he said. Ersoy also said the domestic dynamics of the country must be mobilized otherwise natural events would turn into disasters for buildings housing thousands of children.

Earthquake resistance left at the mercy of foreigners

The professor also heavily criticized the "9th Development Plan" of the government for years between 2007 and 2013. There is no mention of preparations for disasters and resistance against them in that plan, Ersoy said. "The resistance against natural disasters is left to the aid and mercy of foreigners. Of course, we must be open to international collaboration but it is in doubt how much success will be had by a structure based completely on foreign aid. If we can not finish state buildings’ structures for a decade, it shows we are wasting our time," he said.