Earthquake Analysis with Prof. Şener Üşümezsoy
Date: 09 January 2020

Earthquake Analysis with Prof. Şener Üşümezsoy

Prof. Şener Üşümezsoy, Geology professor known with his studies on earthquake, met our students in the discussion organised by the Dean of Students’ Architecture Society.

Within the framework of the Discussion on ‘‘Earthquake Risk in the Marmara region after the Earthquake in Silivri, Geology of the Region of Lakes and its surroundings, and the Effects of the Earthquake’’, Prof. Üşümezsoy shared crucial information with our student in the event held on Hadımköy Campus.

‘‘A 40-km canal does not trigger an earthquake’’

Stating that such sayings that Canal İstanbul Project will trigger an earthquake were not true, Prof. Üşümezsoy said, ‘‘When I look at the data as a geologist, I am saying that a 30 or 40-km canal (Canal İstanbul) will not cause an earthquake. This area is placed on more solid rocks than Beylikdüzü, Avcılar, and Küçükçekmece are. When we look from this perspective, the project will not trigger an earthquake.’’

‘‘The fact that the canal will pollute the water is not true.’’

Emphasising the area’s being on hard ground, Prof. Üşümezsoy went on his words: ‘‘The coastal areas of Avcılar and Küçükçekmece are risky due to the possibility of a landslide. Around the area on which Canal İstanbul will be constructed there are parts of land consist of gravels called gazelle formation in the argillaceous limestone, and there are paleo-landslides in it. Thus; before we build a city where skyscrapers will be constructed on the ground, we have to consider examining the ground, and the faults. This area is placed on more solid rocks than Beylikdüzü, Avcılar, and Küçükçekmece are. When we look from this perspective, the project will not trigger an earthquake. Geologically, we can construct buildings in this area. The fact that the canal will pollute the water is not valid, and when the inside of the canal is covered with concrete, there will be no leak. The ground of this area is more solid than the other coastal areas. Those who are saying that ‘‘An earthquake will occur, do not construct a canal here.’’ today, were the ones that said before ‘‘We have to build a million-dollar city here, the coast will be destroyed.’’

Üşümezsoy stated that he was worried about the Canal İstanbul Project in terms of green areas.

‘‘The severity will be 6.5 of the expected earthquake’’

Mentioning the new studies in the Marmara region, Prof. Üşümezsoy said, ‘‘In this study, the bathymeter of the Marmara Sea was examined in detail. The fault line in Kumburgaz graben lies toward the east, to Yeşilköy. The remarks about this were stating that middle ridge of the Marmara Sea, which we named as the area across Avcılar, made a bathymetry which was cut by a fault. I did not agree with this. The latest data showed that the ridge of the Marmara Sea across Avcılar and Büyükçekmece was not cut by a fault. If we ask what does this mean, we see that the 35-km fault line in Kumburgaz graben ends off the shore in Büyükçekmece. The final location of this fault line which moves to the west (from Silivri graben toward Tekirdağ, and then towards Saroz) is lying towards offshore of Kumburgaz, and ends in Büyükçekmece, which means that the fault may cause an earthquake of which the severity is 6.5. If you add a 40-km fault which lies from Büyükçekmece towards Yeşilköy to this fault line, it will be incorrectly concluded that the severity of the expected earthquake will be 7.2. If you add the fault of Adalar to this, you can say that the severity of the earthquake will be 7.6, caused by a 130-km fault line. This latest study was valid when the fault line in the north of Adalar moved towards the Marmara Sea, but it is not today. This lies towards Yeşiköy, and from Yeşilköy, it lies towards Büyükçekmece. The part inside the sea of the ridge of Beylikdüzü which we mention today is not cut by a fault. The fault in the Kumburgaz graben does not lie towards east.

Prof Üşümezsoy stated that there is a 3 percent possibility that an earthquake of which the severity will be 6.5 will occur in the following years due to Silivri.