Karlıova Üçlü Ekleminde Koda Dalga Analizi

Abstract

Bu çalışmada, Erzincan-Karlıova-Bingöl üçgeni arasında kalan bölgede oluşan 70 adet deprem kullanılarak Koda dalga analizi yapılmıştır. 2006–2008 yıllarında oluşmuş depremlerin B.Ü. KRDEA a ait Bingöl (BINT) istasyonu kayıtları kullanılmıştır. Depremlerin episantır uzaklıkları 15-70 km magnitüdleri 3.1-4.8 ve derinlikleri 5-20 km arasında değişmektedir. Tek saçılma metodu kullanılan çalışmada, 30sn kesme zamanı ile veriler merkez frekansı 1.5, 3, 6, 9, 12 ve 18 Hz olan Butterworth filtresi ile süzgeçlenmiş, sismogramların koda genliklerinin eğimlerinden koda kalite faktörü Qc(f)=45f0.76 olarak hesaplanmıştır. Düşük Qo değeri ve frekansa fazla bağımlılık bölgenin yüksek tektonik aktivitesini karakterize etmektedir.

Coda Wave Analysis in Vicinity of Karliova Triple Junction

Abstract

In the study, we analyzed 70 local earthquakes occurred in vicinity of Karliova Triple Junction. The data were recorded at the network operated by B.U. Kandilli Observatory and Earthquake Research Institute (KOERI) during 2006-2008 at Bingöl station (BINT). The earthquake had epicenter distances between 15 and 70 km, local magnitudes ranging from 3.1 to 4.8 and their focal depths ranging from 5 and 20km. The single scattering method was applied. The quality factor (Qc) calculated at frequencies 1.5, 1.5, 3, 6, 9, 12 and 18 Hz Butterworth filter and a lapse time 30sec. The mean Qc value calculated was Qc(f)=45f0.76. The relatively low Qo and high frequency dependency agree with the values of a region characterized by a high tectonic activity.

References

1. AKI K., CHOUET B., 1975. Origin of coda waves: source, attenuation and scattering effects, J. Geophys. Res. 80, 3322–3342.
2. AKINCI A., EYİDOĞAN H., 1996. Frequency-dependent attenuation of S and codawaves in Erzincan (Turkey), Phys. Earth Planet. Int. 97, 109–119.
3. AKINCI A., TAKTAK G.A. ve ERGİNTAV S., 1996. Batı Anadolu bölgesinde koda dalgalarının soğurulması, Jeofizik, 10, 57-66.
4. DEL PEZZO E., IBANEZ J., MORALES J., AKINCI A. and MARESCA R., 1995. Measurements of intrinsic and scattering seismic attenuation in the crust, Bull. seism. Soc. Am., 85, 1373–1380.
5. EMRE Ö., ÖZALP S., YILDIRIM C., ÖZAKSOY V., DOĞAN A., 2005. 12 ve 14 Mart 2005 Karlıova Depremlerinin Değerlendirilmesi, MTA. Raporu.
6. FEHLER M., HOSHIBA M., SATO H. and OBARA K., 1992. Separation of scattering and intrinsic attenuation for the Kanto-Tokai Region, Japan using measurements of S-wave energy versus hypocentral distance, Geophys. J.Int., 108, 787–800.
7. GIAMPICCOLO E., TUSA G., LANGER H., GRESTA S., 2002. Attenuation in southeastern Sicily (Italy) by applying different coda methods, J. Seismol. 6, 487–501. GIAMPICCOLO E., GRESTA S., RASCONA F., 2004. Intrinsic and scattering attenuation from observed seismic codas in southeastern Sicily (Italy), Phys. Earth Planet. Int. 145, 55–66.
8. GUPTA S.C., TEOTIA S.S., GAUTAM N., 1998. Coda Q estimates in the Koyna region, India. Pure Appl. Geophys. 153, 713–731.

9. HORASAN G., KAŞLILAR A., BOZTEPE A., and TÜRKELLI N., 1998. S- wave attenuation in the Marmara Region, northwestern Turkey, Geophysical Research Letters, 25 (14), 2733-2736.
10. HOSHIBA M., 1991. Simulation of multiple scattered coda wave excitation based on the energy conservation law, Phys. Earth Planet. Inter. 67, 123–136.
11. IBANEZ J.M., DEL PEZZO E.D., MIGUEL F., HERRAIZ M., ALGUACIL G., MORALES J., 1990. Depth-dependent seismic attenuation in the Granada zone (South Spain), Bull. Seismol. Soc. Am. 80, 1232–1244.
12. KNOPOFF, L., 1964. Q.Reviews of Geophysics, 2(4), 625-660.
13. MUKHOPADHYAY S., TYAGI C., RAI S., 2006.The attenuation mechanism of seismic waves in northwestern HimalayasGeophys, J. Int. 167, 354–360.
14. RAUTIAN T.G., KHALTURIN V.I., 1978. The use of the coda for determination of earthquake source spectrum, Bull. Sismol. Soc. Am. 68, 923–948.
15. SATO H., FEHLER M., 1998. SeismicWave Propagation and Scattering in the Heterogeneous Earth, Springer and Verlag, New York, 308 .
16. SATO H., 1977. Energy propagation including scattering effects: single isotropic scattering approximation, J. Phys. Earth 25, 27–41.
17. TRIPATHI J.N., UGALDE A., 2004. Regional estimation of Q from seismic coda observations by the Gauribidanur seismic array (southern India), Phys. Earth Planet. Inter. 145, 115–126.
18. UGALDE A., TRIPATHI JN., HOSHIBA M.,. RASTOGI B.K., 2007. Intrinsic and scattering attenuation in western India from aftershocks of the 26 January, 2001 Kachch earthquake, Tectonophysics 429 111–123.
19. ZENG Y., SU F., AKI K., 1991. Scattered wave energy propagation in a random isotropic scattering medium theory, J. Geophys. Res. 96, 607–619.