Frequency Time Analysis (FTAN) and Moment Tensor Inversion Solutions from Short Period Surface Waves in Cameroon (Central Africa)

Eric N. Ndikum, Charles T. Tabod, Alain-Pierre K. Tokam

Department of Physics, University of Yaounde 1, Yaounde, Cameroon.

DOI: 10.4236/ojg.2014.42004                

Abstract

Short period surface waves generated by a local earthquake recorded by broadband seismometers at distances of about 186 to 778 km from the earthquake’s epicenter located in Cameroon (Central Africa) were processed for group velocity maps and dispersion waveforms using the frequency time analysis (FTAN) method. The resulting group velocity fundamental modes of the extracted Rayleigh and Love waves were used for a joint amplitude spectral and P polarity inversion using moment tensor inversion. The corresponding group velocity dispersion curves, the residual as a function of depth, the amplitude spectra and the moment tensor solutions of the regions from the epicenter to the different stations up to a depth of about 10 km were obtained.

Keywords

Frequency Time Analysis (FTAN); Surface Waves; Group Velocity Dispersion Curves; Moment Tensor Inversion

Conflicts of Interest

The authors declare no conflicts of interest.

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