A new (time-domain) approach for earthquake source parameter inversion

Itzhak Lior

Tel Aviv University

Date & Time
Building 3, Rambo Auditorium
Annemarie Baltay

Determining earthquake source parameters is a challenging task, in part due to the biases and artifacts introduced when transforming the data from the time- to the frequency-domain. In addition, separating the effects of source and attenuation is difficult, especially for small earthquakes. In this study, a new approach for determining the source spectral parameters using the signals in the time domain is presented. Theoretical equations relating source spectral parameters to the root-mean-square of the ground motions (displacement, velocity and acceleration) are derived using the omega squared model of Brune. These relations constitute a set of three independent equations with three unknowns: the displacement low frequency spectral plateau, the source corner frequency and the attenuation parameter. The spectral parameters are obtained in the time domain, and the trade-off between the effects of the corner frequency and the attenuation parameter is quantified and addressed. The results of the new method are compared with those of the standard frequency-domain approach. It is concluded that the new scheme is more stable than the frequency-domain method, resulting in considerably reduced intra-event source parameter variability.

Closed captions are typically available a few days after the seminar. To turn them on, press the ‘CC’ button on the video player. For older seminars that don’t have closed captions, please email us, and we will do our best to accommodate your request.

Video Podcast