Plate tectonics and hotspots: the third dimension.

  title={Plate tectonics and hotspots: the third dimension.},
  author={D. L. Anderson and Toshiro Tanimoto and Yong Sheng Zhang},
  volume={256 5064},
High-resolution seismic tomographic models of the upper mantle provide powerful new constraints on theories of plate tectonics and hotspots. Midocean ridges have extremely low seismic velocities to a depth of 100 kilometers. These low velocities imply partial melting. At greater depths, low-velocity and high-velocity anomalies record, respectively, previous positions of migrating ridges and trenches. Extensional, rifting, and hotspot regions have deep (> 200 kilometers) low-velocity anomalies… CONTINUE READING