FADİME SERTÇELİK, Oral BAŞER

Güney Ege Bölgesi'nde yapay ve doğal kaynaklı titreşimlerin ayırt edilmesi

Güney Ege Bölgesi’nde, Muğla-Aydın arasında kalan kesimde, oluşan sismik olayların kaynak tipinin belirlenmesinin amaçlandığı bu çalışmada; Boğaziçi Üniversitesi, Kandilli Rasathanesi ve Deprem Araştırma Enstitüsü (KRDAE) Ulusal Deprem İzleme Merkezi (UDİM) tarafından kurulan Bodrum (BODT), Dalyan (DALT), Datça (DAT), Milas (MLSB) ve Yerkesik (YER) geniş bant istasyonlarına ait 148 adet sismik olaya ait veri kullanılmıştır. 37.22°-37.50° K enlem ve 26.70°-28.40° D boylamları arasındaki sismik olayların büyüklüğü 2≤Md≤3 ve oluş zamanları 08:00-17:00 (GMT) aralığındadır. Çalışmada sismogramlar zaman ve frekans ortamı yöntemleri ile (S/P genlik oranı - S genliği değişimi ile güç-spektral genlik değişimi) analiz edilmiştir. Depremleri patlatmalardan ayırmak için ise, Doğrusal Ayrım Fonksiyon Analizi kullanılmıştır. Yapılan ayrım analizi sonucunda toplam 148 adet sismik olayın 31 tanesi deprem, 117 tanesi patlatma olarak belirlenmiştir. Zaman ve frekans ortamında uygulanan yöntemlerin sonuçları karşılaştırıldığında % 84 oranında tutarlılık görülmüştür. Deprem ve patlatma kayıtlarını ayırt etmek için, farklı iki ya da daha fazla yöntemin ardarda uygulanmasının, elde edilen sonuçların güvenilirliğini arttırdığı saptanmıştır.

Discrimination of artificial and natural sourced vibrations in the southern Aegean Region

In this study, 148 seismic events recorded by Bodrum (BODT), Dalyan (DALT), Datça (DAT), Milas (MLSB) and Yerkesik (YER) broad-band stations of Boğaziçi University, Kandilli Observatory and Earthquake Research Institute (KOERI), National Earthquake Monitoring Center(NEMC) are used to identify the source type of seismic events occurred between Muğla and Aydın in the Southern Aegean Region. Epicenters and magnitudes of these events are in 37.22°-37.50° N and 26.70°-28.40° E and 2≤Md≤3. Origin times of the events are between 08:00-17:00 (GMT). In this study, time and frequency-domain analysis ( variation of S/P waves ratio- S wave amplitude and variation of power- spectral ratio), were applied to seismograms. Linear discrimination function analysis was used to discriminate earthquakes from blasts. As a result of discrimination analysis of 148 seismic events, 31 of events were determined as earthquakes and 117 of events were determined as quarry blasts. When the results of time and frequency-domain analysis were compared %84 similarity on the results was determined. It is supposed that applying more than two methods in succession increases the success rate of discrimination of earthquakes from blasts.

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