DEUNET (Dokuz Eylül Üniversitesi Sismolojik Gözlem Ağı): Batı Anadolu’da Yeni Bir Yerel Sismik Ağ ile İzmir ve Çevresinin Depremselliği

Abstract

Yerel ve bölgesel sismik ağlar, Batı Anadolu gibi karmaşık tektonizmaya sahip bölgeleri daha iyi incelemek için gereklidir. Yerel sismik ağlar, hem bilim insanlarına hem de ilgili makamlara kritik veriler sağlamaktadır. Ayrıca, Batı Anadolu'nun en büyük şehri olan İzmir'de olması gereken erken uyarı sistemleri için bir temel olarak da değerlendirilmektedir. 15 Şubat 2019'da yeni bir yerel ağ olan DEUNET, Dokuz Eylül Üniversitesi Mühendislik Fakültesi ve Jeofizik Mühendisliği Bölümü'nde, büyük depremlerin yanı sıra mikro deprem aktivitelerini de gözlemlemek, İzmir ve çevresi hakkında yeni ve ayrıntılı bilgiler elde etmek için kuruldu. DEUNET deprem gözlem ağından elde edilen sonuçlar, bu dönemde meydana gelen yerel, bölgesel ve telesismik depremleri tespit etme ve konumlandırma yeteneğine sahip olduğunu göstermektedir. Yapılan değerlendirmelere göre DEUNET istasyon ağının kurulumundan günümüze, İzmir İl’inin özellikle kuzeydoğu ve güneybatısında yoğun bir sismik aktivite gözlenmiştir. Gözlemlediğimiz yoğun sismik aktivitenin nedeni de; Ege Denizi-Sisam ve Manisa depremlerinden dolayı meydana gelen yoğun artçı aktivitesidir. Bu depremler İzmir İl’i ve çevresini etkilemiştir. Bu çalışma kapsamında istasyon ağı tarafından kaydedilen depremlerin odak mekanizması çözümleri de incelenmiştir. Ayrıca kaydedilen depremler kullanılarak istasyon lokasyonlarının zemin özellikleri araştırılmıştır. Batı Anadolu bölgesinde sismoloji eğitimi veren tek üniversite Dokuz Eylül Üniversitesi olduğundan, bu ağın sismoloji eğitiminde de önemli katkıları olmaktadır.

Keywords

• DEUNET
• sismik ağ
• deprem
• sismotektonik
• sismik aktivite

DEUNET (Dokuz Eylul University Seismological Observation Network): Seismicity of Izmir and Its Surroundings with A New Local Seismic Network in Western Anatolia

Abstract

Local and regional networks are needed to better examine the regions with complex tectonism, such as western Anatolia. Local seismic networks may provide critical data to both scientists and local authorities. They are also required as a base for future early warning systems which Izmir, the largest city in the western Anatolia, does not have one. With the support of Dokuz Eylul University, Engineering Faculty and the Department of Geophysical Engineering the installation of a new local network DEUNET established on February 15, 2019, to obtain new and detailed information about Izmir and its surroundings by observing microearthquake activity as well as major and damaging earthquakes in the region. The obtained maps indicate that the network in this period has the capability to detect and locate local, regional and teleseismic earthquakes occurred. According to the results, an intense seismic activity was observed in the northeast and southwest of the station network from its establishment to the present. These recent active areas affected by two large earthquakes which one is called Aegean Sea – Samos earthquake and the other is Manisa earthquake occurred and affected Izmir City and its surroundings. We also examined the focal mechanism solutions of some recorded earthquakes in this paper. In addition, the ground characteristics of the station locations were examined using the recorded earthquakes. Since Dokuz Eylul University is the only university in Western Anatolia that offers seismology education, this network will also provide significant benefits for seismology education.

Keywords

• DEUNET
• seismic network
• earthquake
• seismotectonic
• seismic activity

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