FY 1991 On frequency modulation observed in two PacTOP deep ocean tsunami records González, F.I., and Ye.E. Kulikov In Proceedings, 2nd UJNR Workshop, NGDC Geophysical Record Document No. 24, A.M. Brennan and J.F. Lander (eds.), Honolulu, HI, 56 November 1990, 2729 (1990) Deep ocean tsunami waveforms measured by PacTOP bottom pressure recorders on 30 November 1987 and 6 March 1988 display amplitude and frequency modulation. An analysis of the temporal evolution of spectral energy suggests that frequency dispersion as predicted by classical linear wave theory is an important process governing the evolution of these waveforms. Feature Publications | Outstanding Scientific Publications Contact Sandra Bigley | Help