Skip to main content
Article thumbnail
Location of Repository

Seismic tomography with P and S data reveals lateral variations in the rigidity of slabs

By S. Widiyantoro, B.L.N. Kennett and R.D. van der Hilst


Regional seismic tomography of the northwest Pacific island arcs using P- and S-wave arrival time data with similar\ud path coverage reveals an oceanic lithospheric slab deflected in the mantle transition zone beneath the Izu Bonin region\ud in good agreement with the results of earlier tomographic and other seismic studies in the region. The S-wave images,\ud however, do not show clearly the deflection of the slab. This implies that the stagnant lithospheric slab in the transition zone\ud is more likely a bulk-sound structure, which is strongly supported by our results from joint inversions for bulk-sound and\ud shear wavespeeds. For the Izu Bonin region, where trench migration has been reported, the properties of the deflected slab\ud lying on top of the 660 km discontinuity show strong bulk-sound and weak shear signatures in contrast to the descending\ud slab itself. There is an indication in the shear images that a component of the former oceanic lithosphere is penetrating into\ud the top of the lower mantle, suggesting that a slab split has occurred

Topics: Aardwetenschappen, rigidity, slabs, tomography, P-waves, S-waves
Year: 1999
OAI identifier:
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • (external link)
  • Suggested articles

    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.