Strong Ground Motion

General Earthquake ground motion is the only input for a rational assessment of earthquake loss, earthquake resistant design of structures and understanding of earthquake physics. Although the use of recorded ground motion under similar conditions with the design earthquake is appealing, there may never be an adequate suite of such data in terms of large spatial variability of earthquake ground motion due to tectonic structure, earthquake source processes, path effects, local geology and near-fault conditions. With recent developments in software tools for structural analysis, computing power and structural modelling approaches and techniques that call for time domain transient non-linear dynamic analysis, the demand for real and simulated time histories of ground motion increased substantially.

There are several approaches to the modeling and simulation of strong ground motion in consideration of the physics of the source and propagation processes. Each approach accommodates, to varying degrees, the seismic wave radiation from a fault rupture, propagation through the crust and the modifications by local site conditions.

Current State

We carry out observational and theoretical strong motion studies. Observational studies include permanent strong motion networks and temporary strong motion instrumentation as part of after-shock studies such as the ones operated after the 1992 Erzincan, 1995 Dinar and 1999 Kocaeli and Düzce events. Substantial effort has been devoted to the analysis and interpretation of field-data in view of earthquake source parameters, source models, local site effects and near-field effects. KOERI-EED is the only university unit in Turkey that owns and operates its own urban strong motion network.

There exist some 361 strong motion accelerographs in Turkey. About 158 accelerographs (40% analog, 60% digital) are owned and operated by Earthquake Research Department (ERD) of Ministry of Public Works as the national strong motion network distributed all around Turkey. About 200 digital strong motion accelerographs are owned and operated by KOERI-EED as dense urban network in and around Istanbul (Rapid response and early warning system, structural instrumentations). In addition to ground motion research, the data from this dense urban network is used to provide rapid post-earthquake loss information. Online data from strategically located 10 stations comprise the Istanbul earthquake early warning network.

The empirical database of KOERI-EED is enriched through the seismological data obtained by the National Earthquake Observation Center at KOERI that operates seismographic stations throughout Turkey and two networks in the Marmara region comprising and by General Directorate of Disaster Affairs. We carry out attenuation, site effect, source spectral and source process studies. We utilize empirical, stochastic, deterministic-kinematic, hybrid and Empirical Green’s Functions approaches as forward modeling to synthesize earthquake ground motion. Volume 2 of the European Strong-Motion Database (Ambraseys et al., 2004). This CD ROM is an updated and improved compilation of 462 triaxial strong-motion records from 110 earthquakes and 261 stations in Europe and the Middle East. The data set contains 112 records (about 25% of all data) from Turkey. KOERI-EED contributes about 11% of the records in this data base.



Özel N, T. Sasatani, O. Özel, (2004), A Study of Strong-Ground Motions during the Largest Aftershock (Mw=5.8) of the Kocaeli, Turkey Earthquake, Tectonophysics,

G.Birgören (2004) “Strong Motion Simulation of the 1999 Earthquakes in Western Turkey:  Stochastic Green's Function Technique with Characterized Source Model and Phase Dependent Site Response”, Ph.D. Thesis, Kyoto University, Japan.

G. Birgören, H. Sekiguchi and K. Irikura (2004), "Rupture model of the 1999 Düzce, Turkey, earthquake deduced from high and low frequency strong motion data" Geophysical Research Letters (GRL), Vol.31, L05610.

G. Birgören and K. Irikura (2004) "Stochastic Green’s Function Technique with Phase Dependent Site Response: Case of the Düzce Basin, Turkey" Proc.of the IUGG 2003 Assembly on Seismic Hazard, Risk, and Strong Ground Motion.

Durukal, Y. Çatalyürekli (2004). Assessment of Site Effects in Source Spectral Studies, XXIX General Assembly of the European Seismological Commission, Potsdam, Germany, September 2004.
B. Şanlı, E. Durukal, M. Erdik, (2004) Simulation of Strong Ground Motion For A Large Earthquake in the Marmara Region, XXIX General Assembly of the European Seismological Commision, Potsdam, Germany, September 2004.

E. Durukal, Y.Çatalyürekli (2004).  Spectral Analysis of Source Parameters of the 1999 Kocaeli and Düzce Earthquake Aftershock Sequences, Proceedings of the 13th World Conference on Earthquake Engineering, Vancouver, Canada, Paper No.421.

Erdik M., Durukal E. (2004). Strong Ground Motion, Chapter 3 in Recent Advances in Geotechnical Earthquake Engineering, A. Ansal, Editor, pp. 67-100,  Kluwer Academic Publishers.

Erdik, M, Y.Fahjan, O.Özel, H.Alçık, A.Mert and M.Gül (2003), Istanbul Earthquake Rapid Response  and Early Warning System, Bulletin of Earthquake Engineering, v1, pp.157-163, Kluwer

Durukal E (2002). Critical evaluation of strong motion in Kocaeli and Duzce (Turkey) earthquakes
Soil Dynamics and Earthquake Engineering 22 (7): 589-609 September 2002.

Erdik M., Durukal E. (2002). Simulation Modelling of Strong Ground Motion, in Earthquake Engineering Handbook, W-F. Chen and C. Scawthorn, editors, CRC Press, 2002.

Erdik M, Durukal E (2001). A hybrid procedure for the assessment of design basis earthquake ground motions for near-fault conditions, Soil Dynamics and Earthquake Engineering 21 (5): 431-443 July 2001.

Siyahi, B., E. Durukal ve Z. Altaç (2001) Evaluation of Strong Motion Data from the Kocaeli and Düzce, Turkey Earthquakes in View of Arias Intensity, XVth International Conference on Soil Mechanics and Geotechnical Engineering, Lessons Learned from Recent Strong Earthquakes, Earthquake Geotechnical Engineering Satellite Conference, Proceedings, pp. 189-194. August 2001.

Erdik M., E. Durukal (2000). Assessment of Design Basis Earthquake Ground Motions for Near-Fault Conditions, in Proceedings of the 12 the World Conference on Earthquake Engineering, Paper No: 2361, Auckland, New Zealand, February 2000.

Anderson, J., H. Sucuoglu, A. Erberik, T.Yilmaz, E.Inan, E.Durukal, M.Erdik, R.Anooshehpoor, J. Brune ve S. Ni (2000). ‘‘Strong Ground Motions from the Kocaeli and Düzce, Turkey, Earthquakes and Possible Implications for Seismic Hazard Analysis’’, Earthquake Spectra, Supplement A to Volume 16, 113-137, 2000.

Safak, E., M. Erdik (2000). (Chapter Coordinators);  (in alphabetical order) : K. Beyen, D. Carver, E. Cranswick, M. Celebi, E. Durukal, W. Ellsworth, T. Holzer, M. Meremonte, C. Mueller, C. Mueller, O. Ozel, E. Safak ve S. Toprak (Chapter Contributors), ‘’Recorded Main Shock and Aftershock Motions’’, Earthquake Spectra, Supplement A to Volume 16, 97-112, 2000.

Durukal, E., H. Gökçekuş, M. Gül ve A. Mert (1999). ‘Evaluation of Strong Motion Network Data in North Cyprus’, Proc. of the International Conference on Earthquake Hazard and Risk in the Meditarrenean Region, Vol. I, 301-326, Educational Foundation of Near East University Publications, Lefkoşa, 1999.

Durukal E., M.Erdik, J.Avcı, Ö. Yüzügüllü, Y. Alpay, B. Avar, C. Zülfikar, T.Biro and A.Mert. (1998). Analysis of the Strong Motion Data of the 1995 Dinar, Turkey Earthquake, Soil Dynamics and Earthquake Engineering, Vol. 17, 557-578, 1998.

Erdik M., E.Durukal (1998). Analysis Of The Strong Motion Data Associated With Normal Faulting Mechanism Earthquakes In Turkey, Proceedings of the 6th US National Conference on Earthquake Engineering, Seattle, WA, USA, June 1998.

Durukal E.(1998). Low-frequency, Deterministic Simulation of Strong Ground Motion, Ph.D. Thesis, Bogazici University, Istanbul, Turkey, 1998.

Erdik M., E. Durukal (1997). Assessment of Design Basis Earthquake Ground Motion for Near-Fault Conditions, Proceedings of the First Japan-Turkey Workshop on Earthquake Engineering, Microzonation for Geotechnical Hazards, March 1997, Istanbul, Japan International Corporation Agency and Istanbul Technical University, pp 17-21.

Deodatis G., E. Durukal, A.S. Papageorgiou, M. Shinozuka (1996). Synthesis of Ground Motions of a Loma-Prieta Type Earthquake in the Vicinity of the San Fransisco Metropolitan Area, Proceedings of the 11th World Conference on Earthquake Engineering, Acapulco, Mexico, June 23-28 1996.

Erdik M., E. Durukal, K. Şeşetyan (1995). Empirical Response Spectra, Proceedings of the Third National Conference on Earthquake Engineering, 27-31 March 1995, Istanbul, 714-723.

Ambraseys N., E. Durukal, M. Free (1993). Re-evaluation of Strong-Motion Data from Turkey, Engineering Seismology and Earthquake Engineering Research Report No.93-2, Imperial College of Science and Technology, London, 1993.

Erdik M., E. Durukal (1992). Erzincan Basin, in March 13, 1992 Erzincan Earthquake: A Preliminary Reconnaissance Report, Boğaziçi University, 1992, 61-67.

Erdik M., E. Durukal (1992).  Strong Ground Motion, in March 13, 1992 Erzincan Earthquake: A Preliminary Reconnaissance Report, Boğaziçi University, 1992, 20-47.