Ankara Region Weak and Strong Ground Motion Recording Network


The Purpose and Importance of the Project: Turkey is a country located on the Alpine-Himalaya Earthquake Belt, known to be under a very high earthquake risk with its geological, historical and current earthquakes. Major earthquakes occur due to the faults that make up the North Anatolian Fault System, the East Anatolian Fault System and the Aegean Graben System, and many other faults and serious loss of life and property occur. In short, Turkey is at high earthquake risk, and the buildings in the country and the people living in these structures are also at high earthquake risk.

Due to its location, Ankara is surrounded by the North Anatolian Fault System from the north, the Keskin fault from the southeast, the Tuz Gölü fault from the south, the Ezinepazarı fault from the east and the Eskişehir Fault from the southwest. The mentioned faults are active and have the potential to produce devastating, large earthquakes. Ankara is 80-100 km away from these faults. As a matter of fact, Ankara was significantly affected by the Bolu-Gerede earthquake with a magnitude of 7.2 that occurred on the North Anatolian Fault System in 1944, the Kırşehir-Keskin earthquake with a magnitude of 6.6 that occurred on the Keskin Fault in 1938, and the earthquakes that occurred on the North Anatolian Fault System in 1668. , 2000). Recently, it was also affected by the Orta (Çankırı) and Bala earthquakes, which were smaller than the earthquakes listed above and caused damage. According to Koçyiğit (2000), Central Anatolia is not a region with little seismic activity, as explained in the Turkey Earthquake Zones Map (Ministry of Public Works and Settlement) and some previous researchers (Şengör, 1980) and lasts for 1000-2000 years (perhaps). It is characterized by large earthquakes (with longer intervals), medium-sized earthquakes that occur at intervals of 100-300 years, and small earthquakes that occur with more frequent intervals (10-30), and two separate neotectonic regimes that cause these earthquakes and structures related to these regimes (fault and fault zones). . Pampal (2000) emphasizes that when the historical and current earthquake activity of Ankara and its surroundings are examined, the region is under high earthquake risk and the city center has features that increase earthquake damage in terms of its geological features. According to Ergünay (1978), Ankara is a city that is affected by small earthquakes (M ≤ 5.0) to occur within 50 km area and large earthquakes (M ≥ 7.0) to occur between 70-100 km distances. According to Kasapoğlu (2000), in a major earthquake that may occur in the earthquake source zones that may affect the city, there may be much different damage than the damage caused by the earthquakes in 1938 and 1944, and in order to keep the earthquake risk of the city at the level of 1938 and 1944, it is necessary to build new buildings against earthquakes. stressed the need for special measures to be taken. All these studies show that Ankara is in a dangerous and risky region in terms of earthquakes, and that it may be significantly affected by earthquakes that may occur in its immediate vicinity in the future, as it was in the past. In addition, Ankara settlement area has a special importance in terms of its geological features, as it has features that increase earthquake damage.

For all these reasons, the seismicity of Ankara and its surroundings should be examined in detail. The aim of our project; To establish seismic stations in the city of Ankara and its vicinity to measure weak and strong ground movements due to earthquakes, to measure ground acceleration during an earthquake, to determine the forces that can cause damage to all types of structures due to earthquakes and to contribute to the development of earthquake resistant building techniques with the data obtained here. In addition, another aim of our project is; The aim of this study is to examine the seismicity of Ankara and its vicinity in detail by determining earthquake parameters such as the location, magnitude and depth of the earthquake. With this study, additional information will be provided to scientists who are working on determining the characteristic features of faults in Ankara and its vicinity (type, length, depth, recurrence time, the largest earthquake magnitude that it has created in the past and can create in the future) and the earthquake potential of active faults.

Thus, in the light of the data to be obtained with this project; Developing earthquake-resistant building techniques by measuring the characteristics and seismicity of active faults in Ankara province and its surroundings, source zones that produce and/or have the potential to produce earthquakes, and determination of active faults, earthquake probabilities and hazard-risk calculations, ground accelerations due to earthquakes. It plays an important role in the determination of areas with soil amplification, microzonation studies and soil surveys, to the scientific community, municipalities, public institutions and organizations, to carry out their studies in the light of much healthier data and to reduce earthquake damages by presenting the products to be obtained as a result of the project. It will be ensured that earthquake hazard and risk determination studies can be carried out in a healthy way by using much more detailed data.

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