Warning from Naci Görür for Istanbul: Earthquake intensity will reach 9!

Geoscientist Prof. Dr. Naci Görür issued specific warnings for Istanbul regarding the potential Marmara Earthquake.

Speaking to İpek Özbey from the Sözcü newspaper, Prof. Dr. Naci Görür said the following:

Professor, first I would like to clear up some confusion. Some experts say that the fault line in the Sea of Marmara is a dead line. They claim the actual fault passes in front of the Çınarcık region of Yalova, meaning there is no fault line running along the northern edge of the Marmara. Now there are different interpretations coming from experts, while you have been warning us for years, sometimes even screaming. What is this deep disagreement among experts based on; how can you look at the same place and talk about different results?

- I won't name names, but they are not experts. It is not scientific either. When you say expert, that person must have worked on the subject they are talking about, made observations, collected data, analyzed that data, interpreted it, passed it through the filter of science, and had their work published in an internationally respected journal. This is scientific work, and therefore something an expert can do.

Last week, earthquakes of 5.1 and 4.5 magnitude occurred in the Gemlik district of Bursa. It was felt in the Marmara Region. We started talking about the Istanbul earthquake again. You announced the probability of an earthquake in Istanbul as 47 percent. This also means it might not be 53 percent. What do you base these rates on?

- In geology, almost everything is discussed in terms of probability percentages. We cannot state the entire behavioral pattern of the Earth exactly; it is not like mathematics. One must always say 'it could happen.' It might not happen either, because it won't happen tomorrow, it will happen three days later. The Earth does not behave as humans think.

The 47 percent figure comes from a study Parsons conducted in 2000. There were also Turkish scientists involved. While conducting that study, they examined geological period earthquakes. They examined the stress accumulation on the fault. According to the results based on stress transfer calculations, the probability of an earthquake occurring within 30 years after 1999 was 64 percent. This is a very high probability. This year, Parsons revised this and addressed us from the USA. He said, 'As a result of the revision I made, this probability has dropped to 47 percent.'

How is Istanbul's building stock?

- The geological structure of the Asian side is old, therefore it consists of much more hardened rocks. The European side is younger. Think of it like old cheese versus fresh cheese. The places where you build on the European side consist of young sediments. It does not have enough rock quality. They are sandy, weak rocks containing water. Europe is in this state. Asia, on the other hand, is the exact opposite rock. This greatly affects the building stock and earthquake resistance during an earthquake.

Could you elaborate a bit more; are two examples affected differently by the same earthquake?

- Earthquake waves come from at least 15 kilometers below. They spread globally. Just like how waves come when you throw water into a pool, it's like that. It passes quickly through the solid rock below. First the P-wave comes, then the S-wave.

Which districts will be affected the most?

- Especially the areas located on the European side, the area from the Golden Horn to Silivri, and the parts close to the sea like Bakırköy and Zeytinburnu, these places will be affected more seriously by the earthquake.

Let's say the 47 percent probability happens and there is a very large earthquake in Istanbul. What kind of water problem will we experience?

- In Istanbul, sewage and drinking water lines run side by side. In an earthquake, these will break and be destroyed, and sewage will mix into the drinking water network. Epidemic diseases will be rampant. Water will be cut off, and there will be no hygiene. People will suffer from thirst. Bringing water and distributing it to the public will be a major problem; roads will be blocked. People will not be able to wash.

In your study, where are the riskiest places in terms of water?

- I know them all. I can say that there are more on the European side. Think of a 10-kilometer strip starting from the coast of the Sea of Marmara. There will be much more trouble there. Because the intensity of the earthquake will generally reach 9 from the Golden Horn to Silivri. Being under the influence of an intensity 9 earthquake means this: Even very well-constructed buildings can sustain serious damage.

AFAD has started storing containers in a center established in Silivri to be used in a possible disaster. Is this the right strategy?

- Silivri will be affected by the earthquake at an intensity of 8. You can stockpile there. But this is ultimately the Marmara Region. I think these stockpiles should come from cities outside the Marmara Region, and that aid should be provided from there. I even suggest cooperation with neighboring countries. Because the Marmara Region will be completely affected by this. You have limited capacity to do this by air. What matters is how fast you move within 72 hours. This is the limit for survival. The first emergency response must be stationed outside of Marmara.