A thermochemical boundary layer at the base of Earth's outer core and independent estimate of core heat flux

Geophysical Journal International

Volumn 174, Issue 3, 2008, Pages 1007-1018

  Gubbins, David ^a   Masters, Guy ^b   Nimmo, Francis ^c  

^a UNIVERSITY OF LEEDS   (United Kingdom)

^b UNIVERSITY OF CALIFORNIA   (United States)

^c UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

Acoustic properties; Composition of core; Dynamo: Theories and simulations

Indexed keywords

BODY WAVE; BOUNDARY LAYER; EIGENVALUE; GEODYNAMO; HEAT FLUX; HEAT TRANSFER; OUTER CORE; P-WAVE; SEISMIC VELOCITY; THERMOCHEMISTRY;

EID: 50649087503     PISSN: 0956540X     EISSN: 1365246X     Source Type: Journal    
DOI: 10.1111/j.1365-246X.2008.03879.x     Document Type: Article

References (37)

1. Alfè, D. & Gillan, M.J., 1998. First-principles simulations of liquid Fe-S under Earth's core conditions, Phys. Rev. B, 58, 8248-8256.
2. Alfè, D., Gillan, M.J. & Price, G.D., 1999a. The melting curve of iron at the pressures of the Earth's core conditions, Nature, 401, 462-464.
3. Alfè, D., Price, G.D. & Gillan, M.J., 1999b. Oxygen in the Earth's core: A first-principles study, Phys. Earth planet. Int., 110, 191-210.
4. Alfè, D., Kresse, G. & Gillan, M.J., 2000a. Structure and dynamics of liquid iron under Earth's core conditions, Phys. Rev. B, 61, 132-142.
5. Alfè, D., Price, G.D. & Gillan, M.J., 2000b. Thermodynamic stability of Fe/O solid solution at inner-core conditions, Geophys. Res. Lett., 27, 2417-2420.
6. Alfè, D., Gillan, M.J. & Price, G.D., 2002. Composition and temperature of the Earth's core constrained by combining ab initio calculations and seismic data, Earth planet. Sci. Lett., 195, 91-98.
7. Anderson, D.L., 1989. Theory of the Earth, Blackwell Scientific, Oxford.
8. Braginsky, S.I., 1963. Structure of the F layer and reasons for convection in the Earth's core, Dokl. Akad. Nauk. SSSR Engl. Trans., 149, 1311-1314.
9. Braginsky, S.I. & Roberts, P.H., 1995. Equations governing Earth's core and the geodynamo, Geophys. Astrophys. Fluid Dyn., 79, 1-97.
10. Bullen, K.E. & Bolt, B.A., 1985. An Introduction to the Theory of Seismology, Cambridge University Press, Cambridge, UK.
11. Cao, A.M. & Romanowicz, B., 2004. Constraints on density and shear velocity contrasts at the inner core boundary, Geophys. J. Int., 157, 1146-1151.
12. Doornbos, D.J. & Husebye, E.S., 1972. Array analysis of PKP phases and their precursors, Phys. Earth planet. Int., 5, 387-399.
13. Fearn, D.R. & Loper, D.E., 1983. The evolution of an iron-poor core 1. constraints on the growth of the inner core, in Stellar and planetary magnetism, Vol. 289, pp. 351-370, ed. Soward, A.M., Gordon and Breach, New York.
14. Gubbins, D., Alfè, D., Masters, T.G., Price, D. & Gillan, M.J., 2003. Can the Earth's dynamo run on heat alone? Geophys. J. Int., 155, 609-622.
15. Gubbins, D., Alfè, D., Masters, T.G. & Price, D., 2004. Gross thermodynamics of 2-component core convection, Geophys. J. Int., 157, 1407-1414.
16. Gutenberg, B., 1959. Physics of the Earth's Interior, Academic Press, New York.
17. Haddon, R.A.W. & Cleary, J.R., 1974. Evidence for scattering of seismic PKP waves near the mantle-core boundary, Phys. Earth planet. Int., 8, 211-234.
18. Kaneshima, S., Hirahara, K., Ohtaki, T. & Yoshida, Y., 1994. Seismic structure near the inner core-outer core boundary, Geophys. Res. Lett., 21, 157-160.
19. Kennett, B.L.N., Engdahl, E.R. & Buland, R., 1995. Constraints on seismic velocities in the Earth from traveltimes, Geophys. J. Int., 122, 108-124.
20. Koper, K.D. & Dombrovskaya, M., 2005. Seismic properties of the inner core boundary from PKiKP/P amplitude ratios, Earth planet. Sci. Lett., 237, 680-694.
21. Koper, K.D. & Pyle, M.L., 2004. Observations of PKiKP/PcP amplitude ratios and implications for Earth structure at the boundaries of the liquid core, J. geophys. Res., 109, Art. no. B03301.
22. Labrosse, S., Poirier, J.-P. & Mouël, J.L. L., 2001. The age of the inner core, Earth planet. Sci. Lett., 190, 111-123.
23. Landau, L.D. & Lifshitz, E.M., 1959. Course of Theoretical Physics, Vol. 6: Fluid Mechanics, Pergammon, London.
24. Lay, T. & Wallace, T.C., 1995. Modern Global Seismology, Academic Press, San Diego.
25. Loper, D.E. & Roberts, P.H., 1978. On the motion of an iron-alloy core containing a slurry. 1: General theory, Geophys. Astrophys. Fluid Dyn., 9, 289-321.
26. Loper, D.E. & Roberts, P.H., 1980. On the motion of an iron-alloy core containing a slurry. 2: A simple-model, Geophys. Astrophys. Fluid Dyn., 16, 83-127.
27. Loper, D.E. & Roberts, P.H., 1981. A study of conditions at the inner core boundary of the Earth, Phys. Earth planet. Int., 24, 302-307.
28. Malkus, W.V.R., 1973. Convection at the melting point: A thermal history of the Earth's core, Geophys. Astrophys. Fluid Dyn., 4, 267-278.
29. Masters, T.G. & Gubbins, D., 2003. On the resolution of density within the Earth, Phys. Earth planet. Int., 140, 159-167.
30. Nimmo, F., Price, G., Brodholt, J. & Gubbins, D., 2004. The influence of potassium on core and geodynamo evolution, Geophys. J. Int., 156, 1407-1414.
31. Roberts, P.H., Loper, D.E. & Roberts, M.F., 2003. Convective instability of a mushy layer-I: Uniform permeability, Geophys. Astrophys. Fluid Dyn., 97, 97-134.
32. Shimizu, H., Poirier, J.P. & Le Mouël, J.L., 2005. On crystallization at the inner core boundary, Phys. Earth planet. Int., 151, 37-51.
33. Slater, J.C., 1939. Introduction to Chemical Physics, Dover Publications, New York.
34. Song, X.D. & Helmberger, D.V., 1992. Velocity structure near the inner core boundary from wave-form modeling, J. Geophys. Res.-Solid Earth, 97, 6573-6586.
35. Song, X.D. & Helmberger, D.V., 1995. A P-wave velocity model of Earth's core, J. Geophys. Res.-Solid Earth, 100, 9817-9830.
36. Souriau, A. & Poupinet, G., 1991. The velocity profile at the base of the liquid core from PKP(BC+Cdiff) data-an argument in favor of radial inhomogeneity, Geophys. Res. Lett., 18, 2023-2026.
37. Zou, Z., Koper, K.D. & Cormier, V.F., 2008. The structure of the base of the outer core inferred from seismic waves diffracted around the inner core, J. geophys. Res., 113, B05314.