Overview of the project

Plate subducted into the Earthfs mantle (=slab) tends to once stagnate in the transition region (=stagnant slab) and then fall into the deep lower mantle. We aim at answering why slab tends to stagnate, how it falls and what are geological consequences of slab falling.

We combine ocean bottom seismic and electromagnetic observations with tomographic analyses to reveal the details of the structure of stagnant slab and the surrounding mantle (Projects A01, A02). Also, high temperature/pressure experiments, some of which utilize the largest synchrotron radiation facility, are performed to understand the mechanisms of slab stagnation and subsequent falling (Project A03). Impacts of slab falling on Earthfs history is investigated by mantle convection modeling using Earth Simulator employing the newly obtained detailed structure of the mantle and high temperature/pressure properties of mantle materials (Project A04).

Stagnant slab is a missing link between the Earthfs deep and shallow, and between the past and present. Its comprehensive understanding is expected to open a new window to mantle dynamics.

Copyright 2004-2006 ERI. All rights reserved.