Geodetic observations of very rapid convergence and back-arc extension at the Tonga arc

  title={Geodetic observations of very rapid convergence and back-arc extension at the Tonga arc},
  author={Michael G. Bevis and Frederick W. Taylor and Bob E. Schutz and Jacques R{\'e}cy and Bryan L. Isacks and S. P. Helu and Rajendra Singh and Eric Kendrick and James Stowell and Brian Taylor and Stephane Calmantli},
THE Earth's most active zone of mantle seismicity arises from the subduction of the Pacific plate at the Tonga trench1. It is not known why this slab generates so many more earthquakes than other subducting slabs worldwide. Above the subduction zone the active Tofua (Tonga) volcanic arc is separated by the V-shaped Lau basin from a remnant arc, the Lau ridge, located at the eastern edge of the Australian plate2. The irregular and discontinuous magnetic lineations within the basin have proven… 
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