Nature, Vol.386, No.6625, 578-584, 1997
Evidence for Deep Mantle Circulation from Global Tomography
Seismic tomography based on P-wave travel times and improved earthquake locations provides further evidence for mantle-wide convective now. The use of body waves makes it possible to resolve long, narrow structures in the lower mantle some of which can be followed to sites of present-day plate convergence at the Earth’s surface. The transition from subduction-related linear structures in the mid-mantle to long-wavelength heterogeneity near the core-mantle boundary remains enigmatic, but at least some slab segments seem to sink to the bottom of the mantle.
Keywords:TRAVEL-TIME TOMOGRAPHY;EARTHS MANTLE;SUBDUCTED LITHOSPHERE;LAYERED CONVECTION;NORTHWEST PACIFIC;ISLAND ARCS;HETEROGENEITY;VELOCITY;BENEATH;MODELS