Advertisement

Relationships Between Seismic Wave-Speed, Density, and Electrical Conductivity Beneath Australia from Seismology, Mineralogy, and Laboratory-Based Conductivity Profiles

  • A. KhanEmail author
  • S. Koch
  • T. J. Shankland
  • A. Zunino
  • J. A. D. Connolly
Chapter
Part of the Springer Geophysics book series (SPRINGERGEOPHYS)

Abstract

We present maps of the three-dimensional density (ρ), electrical conductivity (σ), and shear-wave speed (V S) structure of the mantle beneath Australia and surrounding ocean in the depth range of 100–800 km. These maps derived from stochastic inversion of seismic surface-wave dispersion data, thermodynamic modeling of mantle mineral phase equilibria, and laboratory-based conductivity models. Because composition and temperature act as fundamental parameters, we obtain naturally scaled maps of shear-wave speed, density, and electrical conductivity that depend only on composition, physical conditions (pressure and temperature), and laboratory measurements of the conductivity of anhydrous mantle minerals. The maps show that in the upper mantle ρ, σ and V S follow the continental-tectonic division that separates the older central and western parts of Australia from the younger eastern part. The lithosphere beneath the central and western cratonic areas appears to be relatively cold and Fe-depleted, and this is reflected in fast shear-wave speeds, high densities, and low conductivities. In contrast, the lithosphere underneath younger regions is relatively hot and enriched with Fe , which is manifested in slow shear-wave speeds, low densities, and high conductivities. This trend appears to continue to depths well below 300 km. The slow-fast shear-wave speed distribution found here is also observed in independent seismic tomographic models of the Australian region, whereas the coupled slow-fast shear-wave speed, low-high density, and high-low electrical conductivity distribution has not been observed previously. Toward the bottom of the upper mantle at 400 km depth marking the olivine → wadsleyite transformation (the “410-km” seismic discontinuity), the correlation between V S, ρ, and σ weakens. In the transition zone, V S, ρ, and σ are much less correlated indicating a significant compositional contribution to lateral heterogeneity. In particular, in the lower transition zone, σ and ρ appear to be governed mostly by variations in Fe/(Fe + Mg), whereas lateral variations in V S result from changes in (Mg + Fe)/Si and not, as observed in the upper mantle, from temperature variations. Lower mantle lateral variations in thermochemical parameters appear to smooth out, which suggests a generally homogeneous lower mantle in agreement with seismic tomographic images of the lower mantle. As a test of the regional surface-wave-based conductivity model, we computed magnetic fields of 24 h S q variations and compared these to observations. The comparison shows that while our predicted conductivity model improves the fit to observations relative to a one-dimensional model, amplitudes of the computed conductivity anomalies appear not to be large enough to enable these to be discriminated at present.

Keywords

Electrical conductivity Seismic wave-speed Tomography Phase equilibria Surface waves Electromagnetic sounding Mantle composition Mantle temperatures 

Notes

Acknowledgements

We wish to thank J.C. Afonso and an anonymous reviewer for helpful comments as well as T. Koyama, C. Püthe, and A. Kuvshinov for informed discussions. TJS thanks the Office of Basic Energy Sciences, U.S. Department of Energy for support. Numerical computations were performed on the ETH cluster Brutus.

Supplementary material

Video clip of mantle thermochemical anomalies and variations in physical properties beneath Australia. Isotropic mantle shear-wave velocity (first column), electrical conductivity (second column), density (third column), temperature (fourth column), (Mg + Fe)/Si (fifth column, atomic fraction), Fe/(Fe + Mg) (sixth column, atomic fraction), and upper and lower mantle mineral ratios px/(ol + px) and fp/(br + fp) (seventh column, atomic fraction). Shear-wave speed, density, and temperature are given in % deviations from a mean model (Fig. 5.5), respectively. Electrical conductivity is relative to a reference electrical conductivity profile (Fig. 5.5). Mean reference values for all properties are indicated on the right side of each panel. Note that colorbars are inverted for shear-wave speed and conductivity so that fast (slow) velocity anomalies correspond to low (high) conductivities. The models shown here represent 250 samples picked randomly from the posterior distribution. See main text for more details. (MP4 13708 kb).

References

  1. Afonso JC, Ranalli G, Fernandez M, Griffin WL, O’Reilly SY, Faul U (2010) On the Vp/Vs—Mg# correlation in mantle peridotites: implications for the identification of thermal and compositional anomalies in the upper mantle. Earth Planet Sci Lett 289:606CrossRefGoogle Scholar
  2. Afonso JC, Fullea J, Griffin WL, Yang Y, Jones AG, Connolly JAD, O’Reilly SY (2013a) 3D multi-observable probabilistic inversion for the compositional and thermal structure of the lithosphere and upper mantle I: a priori information and geophysical observables. J Geophys Res. doi: 10.1002/jgrb.50124 Google Scholar
  3. Afonso JC, Fullea J, Yang Y, Connolly JAD, Jones AG (2013b) 3D multi-observable probabilistic inversion for the compositional and thermal structure of the lithosphere and upper mantle II: general methodology and resolution analysis. J Geophys Res. doi: 10.1002/jgrb.50123
  4. Berryman JG (1995) Mixture theories for rock properties. In: Ahrens TJ (ed) American geophysical union handbook of physical constants. AGU, New York, p 205Google Scholar
  5. Bina CR (1998) Free energy minimization by simulated annealing with applications to lithospheric slabs and mantle plumes. Pure Appl Geophys 151:605CrossRefGoogle Scholar
  6. Birch F (1961) The velocity of compressional waves in rocks to 10 kilobars, 2. J Geophys Res 66:2199CrossRefGoogle Scholar
  7. Brown JM, Shankland TJ (1981) Thermodynamic parameters in the earth as determined from seismic profiles. Geophys J Int 66:579CrossRefGoogle Scholar
  8. Campbell WH, Barton CE, Chamalaun FH, Webb W (1998) Quiet-day ionospheric currents and their applications to upper mantle conductivity in Australia. Earth Planet Space 50:347CrossRefGoogle Scholar
  9. Chamalaun FH, Barton CE (1993) Electromagnetic induction in the Australian crust: results from the Australia-wide array of geomagnetic stations. Explor Geophys 24:179CrossRefGoogle Scholar
  10. Christensen UR, Hofmann AW (1994) Segregation of subducted oceanic crust in the convecting mantle. J Geophys Res 99(19):867. doi: 10.1029/93JB03403 Google Scholar
  11. Connolly JAD (2005) Computation of phase equilibria by linear programming: a tool for geodynamic modeling and an application to subduction zone decarbonation. Earth Planet Sci Lett 236, doi: 10.1016/j.epsl.2005.04.033
  12. Connolly JAD (2009) The geodynamic equation of state: what and how. Geophys Geochem Geosys 10:Q10014. doi: 10.1029/2009GC002540 Google Scholar
  13. Deschamps F, Trampert J (2003) Mantle tomography and its relation to temperature and composition. Phys Earth Planet Int 140:277CrossRefGoogle Scholar
  14. Deschamps F, Snieder R, Trampert J (2001) The relative density-to-shear velocity scaling in the uppermost mantle. Phys Earth Planet Int 124:193CrossRefGoogle Scholar
  15. Deschamps F, Trampert J, Snieder R (2002) Anomalies of temperature and iron in the uppermost mantle inferred from gravity data and tomographic models. Phys Earth Planet Int 129:245CrossRefGoogle Scholar
  16. Dobson DP, Brodholt JP (2000) The electrical conductivity and thermal profile of the Earth’s mid-mantle. Geophys Res Lett 27:2325CrossRefGoogle Scholar
  17. Drilleau M, Beucler E, Mocquet A, Verhoeven O, Moebs G, Burgos G, Montagner J-P, Vacher P (2013) A Bayesian approach to infer radial models of temperature and anisotropy in the transition zone from surface wave data. Geophys J Int. doi: 10.1093/gji/ggt284
  18. Fabrichnaya OB (1999) The phase in the FeO–MgO–Al2O3–SiO2 system: assessment of thermodynamic properties and phase equilibria at pressures up to 30 GPa. Calphad 23:19CrossRefGoogle Scholar
  19. Fichtner A, Kennett BLN, Igel H, Bunge H-P (2010) Full waveform tomography for radially anisotropic structure: new insights into present and past states of the Australasian upper mantle. Earth Planet Sci Lett 290, doi: 10.1016/j.epsl.2009.12.003
  20. Fishwick S, Rawlinson N (2012) 3-D structure of the Australian lithosphere from evolving seismic datasets. Austr J Earth Sci 59:809CrossRefGoogle Scholar
  21. Forte AM, Perry HC (2000) Geodynamic evidence for a chemically depleted continental tectosphere. Science 290:1940CrossRefGoogle Scholar
  22. Fullea J, Afonso JC, Connolly JAD, Fernandez M, Garcia-Castellanos D, Zeyen H (2009) LitMod3D: an interactive 3D software to model the thermal, compositional, density, rheological, and seismological structure of the lithosphere and sublithospheric upper mantle. Geochem Geophys Geosyst 10:Q08019. doi: 10.1029/2009GC002391 Google Scholar
  23. Fullea J, Muller MR, Jones AG (2011) Electrical conductivity of continental lithospheric mantle from integrated geophysical and petrological modeling: application to the Kaapvaal Craton and Rehoboth Terrane, southern Africa. J Geophys Res 116:B10202. doi: 10.1029/2011JB008544 CrossRefGoogle Scholar
  24. Fullea J, Lebedev S, Agius MR, Jones AG, Afonso JC (2012) Lithospheric structure in the Baikal central Mongolia region from integrated geophysical-petrological inversion of surface-wave data and topographic elevation. Geochem Geophys Geosyst 13, Q0AK09. doi: 10.1029/2012GC004138
  25. Goes S, Govers R, Vacher P (2000) Shallow mantle temperatures under Europe from P and S wave tomography. J Geophys Res 105:11153CrossRefGoogle Scholar
  26. Goes S, Armitage J, Harmon N, Smith H, Huismans R et al (2012) Low seismic velocities below mid-ocean ridges: attenuation versus melt retention. J Geophys Res 117. doi: 10.1029/2012JB009637
  27. Hashin Z, Shtrikman S (1962) A variational approach to the theory of effective magnetic permeability of multiphase materials. J Appl Phys 33:3125CrossRefGoogle Scholar
  28. Helffrich GR, Wood BJ (2001) The Earth's Mantle. Nature 412–501Google Scholar
  29. Hirsch LM, Shankland TJ, Duba AG (1993) Electrical conduction and polaron mobility in Fe-bearing olivine. Geophys J Int 114:36CrossRefGoogle Scholar
  30. Irifune T (1994) Absence of an aluminous phase in the upper part of the Earths lower mantle. Nature 370:131CrossRefGoogle Scholar
  31. Ishii M, Tromp J (2004) Constraining large-scale mantle heterogeneity using mantle and inner-core sensitive normal modes. Phys Earth Planet Inter 146:113CrossRefGoogle Scholar
  32. Jackson I (1998) Elasticity, composition and temperature of the Earths lower mantle: a reappraisal. Geophys J Int 134:291CrossRefGoogle Scholar
  33. Jones AG, Afonso JC, Fullea J, Salajegheh F (2013) The lithosphere-asthenosphere system beneath Ireland from integrated geophysical-petrological modeling—I: observations, 1D and 2D hypothesis testing and modeling. Lithos (in press)Google Scholar
  34. Karato S-I (2011) Water distribution across the mantle transition zone and its implications for global material circulation. Earth Planet Sci Lett 301. doi: 10.1016/j.epsl.2010.1.038
  35. Katsura T, Yoshino T (2015) Heterogeneity of electrical conductivity in the oceanic upper mantle, this volumeGoogle Scholar
  36. Kawai K, Tsuchiya T (2015) Elasticity of continental crust around the mantle transition zone, this volumeGoogle Scholar
  37. Kelbert A, Schultz A, Egbert G (2009) Global electromagnetic induction constraints on transition-zone water content variations. Nature 460. doi: 10.1038/nature08257
  38. Kennett BLN (1998) On the density distribution within the Earth. Geophys J Int 132:374CrossRefGoogle Scholar
  39. Kennett BLN, Fichtner A, Fishwick S, Yoshizawa K (2012) Australian seismological reference model (AuSREM): Mantle component. Geophys J Int 192. doi: 10.1093/gji/ggs065
  40. Khan A, Shankland TJ (2012) A geophysical perspective on mantle water content and melting: inverting electromagnetic sounding data using laboratory-based electrical conductivity profiles. Earth Planet Sci Lett 317–318. doi: 10.1016/j.epsl.2011.11.031
  41. Khan A, Connolly JAD, Olsen N (2006) Constraining the composition and thermal state of the mantle beneath Europe from inversion of long-period electromagnetic sounding data. J Geophys Res 111:B10102. doi: 10.1029/2006JB004270 CrossRefGoogle Scholar
  42. Khan A, Kuvshinov A, Semenov A (2011) On the heterogeneous electrical conductivity structure of the Earth’s mantle with implications for transition zone water content. J Geophys Res 116(B01103):2011. doi: 10.1029/2010JB007458 Google Scholar
  43. Khan A, Zunino A, Deschamps F (2013) Upper mantle compositional variations and discontinuity topography imaged beneath Australia from Bayesian inversion of surface-wave phase velocities and thermochemical modeling. J Geophys Res 118. doi: 10.1002/jgrb.50304
  44. Koch S, Kuvshinov A (2013) Global 3-D EM inversion of Sq-variations based on simultaneous source and conductivity determination. A concept validation and resolution studies. Geophys J Int doi: 10.1093/gji/ggt227
  45. Koyama T, Shimizu H, Utada H, Ichiki M, Ohtani E, Hae R (2006) Water content in the mantle transition zone beneath the North Pacific derived from the electrical conductivity anomaly. In: Jacobsen S, van der Lee S (eds) Earth’s deep water cycle, vol 168. AGU, Washington, DC, p 171 (Geophys Monogr Ser)Google Scholar
  46. Koyama T, Khan A, Kuvshinov A (2014) Three-dimensional electrical conductivity structure beneath Australia from inversion of geomagnetic observatory data: evidence for lateral variations in transition-zone temperature, water content, and melt. Geophys J Int. doi: 10.1093/gji/ggt455
  47. Kuo C, Romanowicz B (2002) On the resolution of density anomalies in the Earth’s mantle using spectral fitting of normal mode data. Geophys J Int 150:162CrossRefGoogle Scholar
  48. Kuskov OL, Panferov AB (1991) Phase diagrams of the FeO–MgO–SiO2 system and the structure of the mantle discontinuities. Phys Chem Minerals 17:642CrossRefGoogle Scholar
  49. Kuskov OL, Kronrod VA, Prokofyev AA, Pavlenkova NI (2014) Thermo-chemical structure of the lithospheric mantle underneath the Siberian craton inferred from long-range seismic profiles. Tectonophysics 615616:154. doi: 10.1016/j.tecto.2014.01.006 CrossRefGoogle Scholar
  50. Kustowski B, Ekström G, Dziewonski AM (2008) Anisotropic shear-wave velocity structure of the Earth’s mantle: a global model. J Geophys Res 113:B06306. doi: 10.1029/2007JB005169 Google Scholar
  51. Kuvshinov A (2012) Deep electromagnetic studies from land, sea and space. Progress status in the past 10 years. Surv Geophys 33. doi: 10.1007/s10712-011-9118-2
  52. Landauer R (1952) The electrical resistance of binary metallic mixtures. J Appl Phys 23:779CrossRefGoogle Scholar
  53. Laske G, Markee A, Orcutt JA, Wolfe CJ, Collins JA, Solomon SC, Detrick RS, Bercovici D, Hauri EH (2011) Asymmetric shallow mantle structure beneath the Hawaiian Swell—evidence from Rayleigh waves recorded by the PLUME network. Geophys J Int 187(1725):2011Google Scholar
  54. Lekic V, Romanowicz B (2012) Tectonic regionalization without a priori information: a cluster analysis of upper mantle tomography. Earth Planet. Sci Lett 308, doi: 10.1016/j.epsl.2011.05.050
  55. Manoj C, Kuvshinov A, Maus S, Lühr H (2006) Ocean circulation generated magnetic signals. Earth Planet Space 58:429CrossRefGoogle Scholar
  56. Manthilake M, Matsuzaki T, Yoshino T, Yamashita S, Ito E, Katsura T (2009) Electrical conductivity of wadsleyite as a function of temperature and water content. Phys Earth Planet Int. doi: 10.1016/j.pepi.2008.06.001
  57. Masters G, Laske G, Bolton H, Dziewonski AM (2000) The relative behaviour of shear velocity, bulk sound speed, and compressional velocity in the mantle: Implications for chemical and thermal structure. In: Karato et al. (eds) Earths deep interior: mineral physics and tomography from the atlantic to the global scale, vol 117. AGU, Washington, DC, p 63 (Geophys Monogr Ser)Google Scholar
  58. Park SK, Ducea MN (2003) Can in situ measurements of mantle electrical conductivity be used to infer properties of partial melts? J Geophys Res 108:2270. doi: 10.1029/2002JB001899 CrossRefGoogle Scholar
  59. Piazzoni AS, Steinle-Neumann G, Bunge HP, Dolejs D (2007) A mineralogical model for density and elasticity of the Earths mantle. Geochem Geophys Geosyst 8:Q11010. doi: 10.1029/2007GC001697 Google Scholar
  60. Poirier JP (2000) Introduction to the physics of the Earth’s interior, 2nd edn. Cambridge University Press, Cambridge, p 312Google Scholar
  61. Pommier A (2014) Interpretation of magnetotelluric results using laboratory measurements. Surv Geophys 35. doi: 10.1007/s10712-013-9226-2
  62. Püthe C, Kuvshinov A, Olsen N (2015) Handling complex source structures in global EM induction studies: from C-responses to new arrays of transfer functions. Geophys J Int 201, doi: 10.1093/gji/ggv021
  63. Rawlinson N, Kennett BLN, Salmon M, Glen RA (2015) Origin of lateral heterogeneities in the upper mantle beneath south-east australia from seismic tomography, this volumeGoogle Scholar
  64. Resovsky JS, Ritzwoller MH (1999) Regularization uncertainty in density models estimated from normal mode data. Geophys Res Lett 26:2319CrossRefGoogle Scholar
  65. Resovsky J, Trampert J (2003) Using probabilistic seismic tomography to test mantle velocity-density relationships. Earth Planet Sci Lett 215:121CrossRefGoogle Scholar
  66. Ricard Y, Mattern E, Matas J (2005) Synthetic tomographic images of slabs from mineral physics. In: Hilst RVD, Bass JD, Matas J, Trampert J (eds) Earths deep Mantle: structure, composition, and evolution. AGU, Washington, DC, pp 283–300Google Scholar
  67. Ricolleau et al (2009) Density profile of pyrolite under the lower mantle conditions. Geophys Res Lett 36:L06302. doi: 10.1029/2008GL036759 CrossRefGoogle Scholar
  68. Romanowicz B (2001) Can we resolve 3D density heterogeneity in the lower mantle? Geophys Res Lett 28:1107CrossRefGoogle Scholar
  69. Saltzer RL, van der Hilst RH, Karason H (2001) Comparing P and S wave heterogeneity in the mantle. Geophys Res Lett 28:1335CrossRefGoogle Scholar
  70. Saxena SK, Eriksson G (1983) Theoretical computation of mineral assemblages in pyrolite and lherzolite. J Petrol 24:538CrossRefGoogle Scholar
  71. Schaeffer AJ, Lebedev S (2015) Global heterogeneity of the lithosphere and underlying mantle: a seismological appraisal based on multimode surface-wave dispersion analysis, shear-velocity tomography, and tectonic regionalization, this volumeGoogle Scholar
  72. Schmerr N (2015) Imaging mantle heterogeneity with upper mantle seismic discontinuities, this volumeGoogle Scholar
  73. Semenov A, Kuvshinov A (2012) Global 3-D imaging of mantle electrical conductivity based on inversion of observatory C-responses—II. Data analysis and results. Geophys. J Int. doi: 10.1111/j.1365-246X.2012.05665.x
  74. Shankland TJ (1972) Velocity-density systematics: derivation from Debye theory and the effect of ionic size. J Geophys Res 77:3750CrossRefGoogle Scholar
  75. Shankland TJ (1977) Elastic properties, chemical composition, and crystal structure of minerals. Surv Geophys 3:89Google Scholar
  76. Shankland TJ (1981) Electrical conduction in Mantle materials. In: O’Connell RJ, Fyfe WS (eds) Evolution of the Earth, American Geophysical Union, vol 5. Washington, DC. p 256, doi: 10.1029/GD005p0256
  77. Shankland TJ, O’Connell RJ, Waff HS (1981) Geophysical constraints on partial melt in the upper mantle. Rev Geophys Space Phys 19:394CrossRefGoogle Scholar
  78. Shimizu H, Utada H, Baba K, Koyama T, Obayashi M, Fuka Y (2010) Three-dimensional imaging of electrical conductivity in the mantle transition zone beneath the North Pacific Ocean by a semi-global induction study. Phys Earth Planet Int 183. doi: 10.1016/j.pepi.2010.01.010
  79. Simmons NA, Forte AM, Grand SP (2009) Joint seismic, geodynamic and mineral physical constraints on three-dimensional mantle heterogeneity: Implications for the relative importance of thermal versus compositional heterogeneity. Geophys J Int 177:1284CrossRefGoogle Scholar
  80. Sobolev SV, Babeyko AY (1994) Modeling of mineralogical composition, density and elastic-wave velocities in anhydrous magmatic rocks. Surv Geophy 15:515CrossRefGoogle Scholar
  81. Stixrude L, Lithgow-Bertelloni C (2005) Thermodynamics of mantle minerals I. Physical properties. Geophys J Int 162:610CrossRefGoogle Scholar
  82. Stixrude L, Lithgow-Bertelloni C (2011) Thermodynamics of mantle minerals II. Phase equilibria. Geophys J Int 184:1180CrossRefGoogle Scholar
  83. Tarits P, Mandea M (2010) The heterogeneous electrical conductivity structure of the lower mantle. Phys Earth Planet Int 183. doi: 10.1016/j.pepi.2010.08.002
  84. Toffelmier DA, Tyburczy JA (2007) Electromagnetic detection of a 410-km-deep melt layer in the Southwestern United States. Nature 447. doi: 10.1038/nature05922
  85. Trampert J, Van der Hilst RD (2005) Towards a quantitative interpretation of global seismic tomography. In: Van der Hilst RD, Bass JD, Matas J, Trampert J (eds) Earth's Deep Interior: Structure, Composition, and Evolution, Geophysical Monograph 160. American Geophysical Union, Washington, p 47–62Google Scholar
  86. Utada, H., Koyama, T., Obayashi, M., Fukao, Y., 2009. A joint interpretation of electromagnetic and seismic tomography models suggests the mantle transition zone below Europe is dry, Earth Planet Sci Lett. doi: 10.1016/j.epsl.2009.02.027
  87. Verhoeven O et al (2009) Constraints on thermal state and composition of the Earth’s lower mantle from electromagnetic impedances and seismic data. J Geophys Res 114:B03302. doi: 10.1029/2008JB005678 Google Scholar
  88. Wang CY (1970) Density and constitution of the mantle. J Geophys Res 75:3264CrossRefGoogle Scholar
  89. Watt JP, Davies GF, O’Connell RJ (1976) The elastic properties of composite materials. Rev Geophys Space Phys 14:541CrossRefGoogle Scholar
  90. Wood BJ, Holloway JR (1984) A thermodynamic model for subsolidus equilibria in the system CaO–MgO–Al2O3–SiO2. Geochim Cosmochim Acta 66:159CrossRefGoogle Scholar
  91. Xie S, Tackley PJ (2004) Evolution of helium and argon isotopes in a convecting mantle. Phys Earth Planet Inter 146:417. doi: 10.1016/j.pepi.2004.04.003 CrossRefGoogle Scholar
  92. Xu Y, Shankland TJ, Poe BT (2000) Laboratory-based electrical conductivity in the Earth’s mantle. J Geophys Res 108:2314CrossRefGoogle Scholar
  93. Yoshino T (2010) Laboratory electrical conductivity measurement of mantle minerals. Surv Geophys 31:163206. doi: 10.1007/s10712-009-9084-0
  94. Yoshino T, Katsura T (2013) Electrical conductivity of mantle minerals: role of water in conductivity anomalies. Ann Rev Earth Planet Sci 41. doi: 10.1146/annurev-earth-050212-124022
  95. Yoshino T et al (2012) Effect of temperature, pressure and iron content on the electrical conductivity of olivine and its high-pressure polymorphs. J Geophys Res 117:B08205. doi: 10.1029/2011JB008774 Google Scholar

Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  • A. Khan
    • 1
    Email author
  • S. Koch
    • 1
  • T. J. Shankland
    • 2
  • A. Zunino
    • 3
  • J. A. D. Connolly
    • 4
  1. 1.Institute of GeophysicsETH ZürichZürichSwitzerland
  2. 2.Geophysics GroupLos Alamos National LaboratoryLos AlamosUSA
  3. 3.Niels Bohr InstituteUniversity of CopenhagenCopenhagenDenmark
  4. 4.Institute of Geochemistry and PetrologyETH ZürichZürichSwitzerland

Personalised recommendations