Hybrid numerical modelling of T-wave propagation:application to the Midplate experiment

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

12

Scientific paper

A hybrid method, coupling a ray tracing method and a finite difference approach, is proposed for modelling T-wave propagation from an underwater source to an on-land seismic station. The long-range hydroacoustic wavefield, estimated in the SOFAR channel by the Maslov approach, shows many triplications of propagation with an increasing number of caustics as the range increases. Ray tracing approaches lead to a straightforward analysis of the SOFAR propagation: we find that the duration and the amplitude of the hydroacoustic T waves generated by a source close to the SOFAR axis may be respectively eight times longer and almost seven times higher than the duration and the amplitude of hydroacoustic T waves generated by a source close to the SOFAR limits. The finite difference modelling handles the complex hydroacoustic-seismi c T-wave conversion on atoll shores with an illustration of seismic T waves recorded during the Midplate experiment in 1989. Two different seismic stations, FGA on the Fangataufa Atoll and DIN on the Mururoa Atoll, both in French Polynesia, have recorded the seismic T waves due to an underwater chemical blast at a distance greater than 900 km. Synthetic seismograms computed by our proposed hybrid method are close enough to the real data for quantitative interpretation. We believe that the input model structure is accurate enough to allow such analysis of the seismic T waves. The numerical simulation shows that the seismic T waves recorded at both stations are mainly composed of P phases and Rayleigh phases. The simulation shows that the seismic T-wave duration is often linked to the source depth, although other factors (the continental slope or the distance between the top of the continental slope and the seismic station) may also affect the signal duration.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Hybrid numerical modelling of T-wave propagation:application to the Midplate experiment does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Hybrid numerical modelling of T-wave propagation:application to the Midplate experiment, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hybrid numerical modelling of T-wave propagation:application to the Midplate experiment will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1331972

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.