Deep Mantle Seismic Modeling and Imaging Thorne Lay 1 and Edward J. Garnero 2 1 Department of Earth and Planetary Sciences, University of California, Santa Cruz, Santa Cruz, California 95064; email: tlay@ucsc.edu 2 School of Earth and Space Exploration, Arizona State University, Tempe, Arizona 85287-1404; email: garnero@asu.edu Annu. Rev. Earth Planet. Sci. 2011. 39:91–123 First published online as a Review in Advance on January 27, 2011 The Annual Review of Earth and Planetary Sciences is online at earth.annualreviews.org This article’s doi: 10.1146/annurev-earth-040610-133354 Copyright c  2011 by Annual Reviews. All rights reserved 0084-6597/11/0530-0091$20.00 Keywords lower-mantle structure, D  , core-mantle boundary, ultralow-velocity zones, thermochemical anomalies, superplumes Abstract Detailed seismic modeling and imaging of Earth’s deep interior is provid- ing key information about lower-mantle structures and processes, including heat flow across the core-mantle boundary, the configuration of mantle up- wellings and downwellings, phase equilibria and transport properties of deep mantle materials, and mechanisms of core-mantle coupling. Multichannel seismic wave analysis methods that provide the highest-resolution deep man- tle structural information include network waveform modeling and stacking, array processing, and 3D migrations of P- and S-wave seismograms. These methods detect and identify weak signals from structures that cannot be re- solved by global seismic tomography. Some methods are adapted from oil exploration seismology, but all are constrained by the source and receiver dis- tributions, long travel paths, and strong attenuation experienced by seismic waves that penetrate to the deep mantle. Large- and small-scale structures, with velocity variations ranging from a fraction of a percent to tens of per- cent, have been detected and are guiding geophysicists to new perspectives of thermochemical mantle convection and evolution. 91 Annu. Rev. Earth Planet. Sci. 2011.39:91-123. Downloaded from www.annualreviews.org by University of California - Santa Cruz on 04/28/11. For personal use only.