Abstract
TeleseismicP-waves of some large earthquakes that occurred in the eastern Mediterranean region have been analysed by using an iterative maximum entropy technique in order to obtain the independent spectral parameters, the long-period spectral level Ω0 and the corner frequencyf 0 of the far-field displacement spectra.
Based on these parameters, the seismic source parameters seismic momentM 0, source dimensionr, fault lengthl, average displacement 〈u〉, shear stress drop Δσ, radiated energyE s and apparent stressn 〈σ〉 are calculated for the considered earthquakes by using Brune's and Madariaga's models.
The striking feature of the source parameters obtained in this study is the low stress drop value which varies between 5 and 15 bars. If Madariaga's model had been used, higher stress drop values would have been obtained.
The low stress drop earthquakes in the eastern Mediterranean region might be interpreted either by the possible presence of low strength material near the source or by the partial stress drop model.
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Stavrakakis, G.N., Blionas, S.V. Source parameters of some large earthquakes in the eastern Mediterranean region based on an itertive maximum entropy technique. PAGEOPH 132, 679–698 (1990). https://doi.org/10.1007/BF00876813
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DOI: https://doi.org/10.1007/BF00876813