Thorsten W. Becker

Jackson School of Geosciences
The University of Texas at Austin

Seismic tomography


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downloads: [software] [tomography] [visualizations]
[global maps] [SKS compilation] [APM model] [LPO model]
[lecture notes] [papers]

  • Composite mantle models

    Becker and Boschi (2002) argued that stacking of existing models may be a way to emphasize robust mantle structure for geodynamic analysis. This seems to work in terms of outperforming other models for exercises such as fitting the geoid (e.g. Steinberger and Calderwood, 2006), and fit to actual seismological data is preserved or enhanced (Qin et al., 2009).

    Follow the links below for

  • SAVANI: radially anisotropic mantle tomography model

    SAVANI is a whole-mantle, shear-wave velocity tomography model that allows for variable parametrization and combines a wide array of surface wave (fundamental plus overtone) and body wave data, inverting for radial anistropy and Voigt velocities (Auer et al., 2014). SAVANI should be one of the best resolved, global, radially anisotropic tomography models today.
    • Auer, L., Boschi , L., Becker, T. W., Nissen-Meyer, T. and Giardini, D.: Savani: a variable-resolution whole-mantle model of anisotropic shear-velocity variations based on multiple datasets. J. Geophys. Res., 119, 3006-3034, doi:10.1002/2013JB010773, 2014. (PDF)
    • download SAVANI
    • download a fancy figure
  • SMEAN2 composite tomography model

    SMEAN2 is a global, composite mantle tomography models constructed following the approach Becker and Boschi (2002) used for SMEAN, but using newer models. In particular, SMEAN2 is based on
    1. S40RTS: Ritsema J., van Heijst H. J., Deuss A., Woodhouse J. H., S40RTS: a degree-40 shear-velocity model for the mantle from new Rayleigh wave dispersion, teleseismic traveltimes, and normal-mode splitting function measurements, Geophys. J. Int., 184, doi:10.1111/j.1365–246X.2010.04884.x, 2011.
    2. GyPSUM-S: Simmons, N. A., A. M. Forte, L. Boschi, S. P. Grand. GyPSuM: A joint tomographic model of mantle density and seismic wave speeds. J. Geophys. Res. 115 doi:10.1029/2010JB007631, 2010.
    3. SAVANI: Auer, L., Boschi , L., Becker, T. W., Nissen-Meyer, T. and Giardini, D.: Savani: a variable-resolution whole-mantle model of anisotropic shear-velocity variations based on multiple datasets. J. Geophys. Res., 119, 3006-3034, doi:10.1002/2013JB010773, 2014.
    See The correlation up to spherical harmonic degree 20 is ~0.88.
  • SMEAN-WUS and PMEAN-WUS composite western United States upper mantle tomography models


    These MEAN-WUS models are averages of SH11 (Schmandt and Humphreys, 2010), DNA09 (Obrebski et al., 2010), and NWUS (James et al., 2011), constructed for my comparative analysis of tomographic models.
  • SMEAN and PMEAN composite tomography models

    SMEAN and PMEAN are global, composite mantle tomography models constructed by Becker and Boschi (2002) by averaging existing, similar S and P wave models with the goal to emphasize common structure. In particular,
    • SMEAN is based on
      1. s20rts: Ritsema, J., and H. J. van Heijst, Seismic imaging of structural heterogeneity in Earth’s mantle: Evidence for large-scale mantle flow, Sci. Progr., 83, 243-259, 2000.
      2. sb4l18: Masters, G., H. Bolton, and G. Laske, Joint seismic tomography for P and S velocities: How pervasive are chemical anomalies in the mantle?, Eos Trans. AGU, 80(17), Spring Meet. Suppl., S14, 1999.
      3. nGrand: The 2001 update of Grand, S. P., R. D. van der Hilst, and S. Widiyantoro, Global seismic tomography; A snapshot of convection in the Earth, GSA Today, 7, 1-7, 1997.
    • PMEAN is based on
      1. bdp00: An update of Boschi, L., and A. M. Dziewonski, "High" and "low" resolution images of the Earth's mantle - Implications of different approaches to tomographic modeling, J. Geophys. Res., 104, 25,567 - 25,594, 1999.
      2. kh00P: Karason, H., and R. D. van der Hilst, Tomographic imaging of the lowermost mantle with differential times of refracted and diffracted core phases (PKP, Pdiff), J. Geophys. Res., 106, 6569 - 6588, 2001.

    SMEAN is often found to outperform other models with respect to predicting geophysical observables such as the geoid (Steinberger and Calderwood, 2006). SMEAN also leads to the highest correlations of velocity anomalies with deep mantle plumes (Boschi et al., 2008), and does as well, or better than, the original models when comparing full wave forms (Qin et al., 2009). A reference is

    • Becker, T. W. and Boschi, L.: A comparison of tomographic and geodynamic mantle models, Geochem., Geophys., Geosyst., 3 (1), 1003, doi:10.1029/2001GC000168, 2002. (PDF)

    SMEAN and PMEAN can be downloaded in the original spherical harmonics format of Becker and Boschi (2002) (download spherical harmonics handling tools here or on GitHub), or expanded into GMT/Netcdf grids (REAMDE files included)

    Also see the 2016 update model SMEAN2.

  • A comparison of global mantle tomography models

    You can find the additional online material and tomographic model expansions from
    • Becker, T. W. and Boschi, L.: A comparison of tomographic and geodynamic mantle models, Geochem., Geophys., Geosyst., 3 (1), 1003, doi:10.1029/2001GC000168, 2002. (PDF)
    on the Becker and Boschi: Correlations between tomographic models page. For example: The software for converting global tomography models from the common format global tomography model files from spherical harmonics to spatial GMT/Netcdf grids can be found on the software page, under "shansyn". SEATREE can compute mantle flow and the geoid from these files.

    An updated version that compares more recently developed models is in the works.

  • Solid Earth Research and Teaching Environment (SEATREE) modules

    All of the SEATREE tools below are installed within the our Unified Geodynamics Earth Science Computing Environment Virtual Box distribution:
    • hc can compute the geoid and mantle flow from the spherical harmonics format used on by shansyn and on our tomography repository.
    • larry3D is a 3-D, global body-wave tomography tool
    • larry is a 2-D, global surface-wave, phase velocity tomography tool
    • syn2d is a 2-D, synthetic tomography teaching tool
  • Some of our tomography related publications

    • Auer, L., Becker, T. W., Boschi, L., and Schmerr, N.: Thermal structure, radial anisotropy, and dynamics of oceanic boundary layers. Geophys. Res. Lett., 42, 9740-9749, doi:10.1002/2015GL066246, 2015. (PDF)
    • Auer, L., Boschi , L., Becker, T. W., Nissen-Meyer, T. and Giardini, D.: Savani: a variable-resolution whole-mantle model of anisotropic shear-velocity variations based on multiple datasets. J. Geophys. Res., 119, 3006-3034, doi:10.1002/2013JB010773, 2014. (PDF, model download, figure)
    • Schmandt, B., Jacobsen, S. D., Becker, T. W., Liu, Z., and Dueker, K. G.: Dehydration melting at the top of the lower mantle. Science, 334, 1265-1268, 2014. (PDF)
    • Becker, T. W. On recent seismic tomography for the western United States. Geochem., Geophys., Geosys., 13, Q01W10, doi:10.1029/2011GC003977, 2012. (PDF)
    • Schaefer, J. F., Boschi, L., Becker, T. W. and Kissling, E.: Radial anisotropy in the European mantle: Tomographic studies explored in terms of mantle flow. Geophys. Res. Lett., 38, L23304, doi:10.1029/2011GL049687, 2011. (PDF)
    • Boschi, L. and Becker, T. W.: Vertical coherence in mantle heterogeneity from global seismic data. Geophys. Res. Lett., 38 (L20306), doi:10.1029/2011GL049281, 2011. (PDF)
    • Bull, A. L., McNamara, A. K., Becker, T. W., and Ritsema, J.: Global scale models of the mantle flow field predicted by synthetic tomography models. Phys. Earth Planet. Int., 182, 129-138, 2010. (PDF)
    • Foley, B. and Becker, T. W.: Generation of plate-like behavior and mantle heterogeneity from a spherical, visco-plastic convection model. G-Cubed,Geochem., Geophys., Geosys., 10, Q08001, doi:10.1029/2009GC002378, 2009. (PDF)
    • Qin, Y., Capdeville, Y., Montagner, J.-P., Boschi, L., and Becker, T. W.: Reliability of mantle tomography models assessed by spectral-element simulation. Geophys. J. Int., 177, 125-144, 2009. (PDF)
    • Boschi, L., Becker, T. W., and Steinberger, B.: On the statistical significance of correlations between synthetic mantle plumes and tomographic models. Physics Earth Planet. Int., 260, 230-238, 2008. (PDF)
    • Boschi, L., T. W. Becker, and B. Steinberger, Mantle plumes: Dynamic models and seismic images, Geochem. Geophys. Geosyst., 8, Q10006, doi:10.1029/2007GC001733, 2007. (PDF)
    • Boschi, L., Becker, T. W., Soldati, G., and Dziewonski, A. M.: On the relevance of Born theory in global seismic tomography. Geophys. Res. Lett., 33, L06302, doi:10.1029/2005GL025063, 2006. (PDF).
    • Becker, T. W. and Boschi, L.: A comparison of tomographic and geodynamic mantle models, Geochem., Geophys., Geosyst., 3, (1), 1003, doi:10.1029/2001GC000168, 2002. (PDF)

[news] [research] [teaching] [group] [publications] [CV] [contact]
downloads: [software] [tomography] [visualizations]
[global maps] [SKS compilation] [APM model] [LPO model]
[lecture notes] [papers]

Updated: December 13, 2018. (c) JSG Geodynamics, 2018.