Propagation des ondes longitudinales dans le noyau terrestre d'après les séismes profonde des Iles Fidji

Observations from three deep focus earthquakes, of focal depth 600 km, originating in the Fiji Islands region, have permitted to trace the travel-time curves for the longitudinal waves travelling through the earth's core. Of principal importance is the travel-time table for the phase PKP1 which has been given upto 158° and for which the data so far were incomplete. Other important phases observed between 103 and 143° have been illustrated and their travel-time curves drawn.

Sur les ondes T des séismes des Philippines enregistrées à Nhatrang

According to the authors, T waves recorded at Nhatrang from Philippine Islands earthquakes may present 3 important phases: F and G, T. and M. If h is the depth of the earthquake, a and b the land paths of T waves respectively near the epicenter and the station, these phases may be noted as: ph-Sofar-SV sub(b) for F and G; P sub(a)-Sofar-SV sub(b) for T sub(2) and problably S in sediments, for M. Sofar waves velocity in China sea, between Philippine and Vietnam, has been determined as to be: 1.48 ± 0.03km

Propagation des ondes longitudinales dans le noyau terrestre: résumé et conclusion

Six earthquakes (magnitude 6 to 7) in the Fiji Islands, New Hebrides and Sulawesi, divided in two groups of depth h=100 to 200 km and h= 600 km, were studied through more than a thousand of seismographic observations in 16 months.