Lithospheric thickness in the western Pacific

Rayleigh wave phase velocities were determined by the single-station method for ten paths in the western Pacific. The data show that even 100 m.y. after formation, the phase velocity and upper-mantle structure are still dependent upon age. Inversion of the data gave a model with a lithospheric thickness of 76 km at 100 m.y., increasing to 104 km at 150 m.y., measured from the base of the crust.