| Abstract: | Refraction seismic data obtained from a sonobuoy (SB7) in the East China Sea shelf marginal ridge was processed and interpreted. Intercept times and layer velocities were used to set up a one-dimension depth-velocity model based on which a two-dimenssion depth-velocity crustal model was established through two-dimension ray-tracing . The computation results showed that the upper crustal depth-velocity model beneath lineSB7 is composed of four layers with primary wave velocities of 1.80-2.20, 2.85-2.90 3.24- 3.34 and 4.55-6.00 m/s respectively . Neighbouring reflection seismic data and data on the East Chna Sea(ECS) regional geology were used to study the reationship between the velocities and their formation ages and also the contact reationship between the velocity boundaries . |
