Abstract
The effects of the seismic attenuation pattern observed at the bend of the
Southeastern Carpathians on the peak ground motions (PGMs) produced by local crustal
earthquakes are analyzed using theoretical experiments. The synthetic seismograms –
ground velocity time histories, vertical component – are calculated by the multimodal
summation method in layered inelastic media. The theoretical waveforms evidence that
the lateral variations of the attenuation structure may result in higher peak amplitudes at
larger epicentral distances, in other words, the wave attenuation may dominate the wave
spreading in the study area, within epicentral distances up to a few tens of km. The result
is in good agreement with the observations, and emphasize the substantial contribution of
the crustal attenuation to the pattern of ground motions caused by crustal, as well as
intermediate-depth earthquakes of Vrancea.
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