Subduction of the Chile Ridge: Upper mantle structure and flow

  title={Subduction of the Chile Ridge: Upper mantle structure and flow},
  author={R. Russo and J. Vandecar and D. Comte and V. Mocanu and A. Gallego and R. Murdie},
  journal={Gsa Today},
We deployed 39 broadband seismometers in southern Chile from Dec. 2004 to Feb. 2007 to determine lithosphere and upper mantle structure in the vicinity of the subducting Chile Ridge. Body-wave travel-time tomography clearly shows the existence of a long-hypothesized slab window, a gap between the subducted Nazca and Antarctic lithospheres. P-wave velocities in the slab gap are distinctly slow relative to surrounding asthenospheric mantle. Thus, the gap between slabs visible in the imaging… Expand

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