Solid Earth www.solid-earth.net 1869-9510 1869-9529 1 1 2010 10.5194/se-1-5-2010 http://www.solid-earth.net/1/5/2010/ http://www.solid-earth.net/1/5/2010/se-1-5-2010.html http://www.solid-earth.net/1/5/2010/se-1-5-2010.pdf 5 24 2010-02-22 Earth's surface heat flux J. H. Davies daviesjh2@cardiff.ac.uk D. R. Davies School of Earth and Ocean Sciences, Cardiff University, Main Building, Park Place, Cardiff, CF103YE, Wales, UK Department of Earth Science & Engineering, Imperial College London, South Kensington Campus, London, SW72AZ, UK We present a revised estimate of Earth's surface heat flux that is based upon a heat flow data-set with 38 347 measurements, which is 55% more than used in previous estimates. Our methodology, like others, accounts for hydrothermal circulation in young oceanic crust by utilising a half-space cooling approximation. For the rest of Earth's surface, we estimate the average heat flow for different geologic domains as defined by global digital geology maps; and then produce the global estimate by multiplying it by the total global area of that geologic domain. The averaging is done on a polygon set which results from an intersection of a 1 degree equal area grid with the original geology polygons; this minimises the adverse influence of clustering. These operations and estimates are derived accurately using methodologies from Geographical Information Science. We consider the virtually un-sampled Antarctica separately and also make a small correction for hot-spots in young oceanic lithosphere. A range of analyses is presented. These, combined with statistical estimates of the error, provide a measure of robustness. Our final preferred estimate is 47±2 TW, which is greater than previous estimates. Beardsmore, G. R. and Cull, J. P.: Crustal Heat Flow, Cambridge University Press, Cambridge, 2001. Buffett, B. A.: Estimates of heat flow in the deep mantle based on the power requirements for the geodynamo, Geophys. Res. Lett., 29, 1566, doi:1510.1029/2001GL014649, 2002. Buffett, B. A.: The thermal state of Earth's core, Science, 299, 1675–1677, 2003. Christensen, U. R. and Tilgner, A.: Power requirement of the geodynamo from ohmic losses in numerical and laboratory dynamos, Nature, 429, 169–171, doi:10.1038/nature02508, 2004. Commission for the Geological Map of the World: Geological Map of the World at 1:25000000, 2nd Edn., UNESCO/CCGM, 2000. Davies, G. F.: Ocean bathymetry and mantle convection 1. Large flow and hotspots, J. Geophys Res., 93, 10467–10480, 1988. Davis, E. and Elderfield, H. (Eds.): Hydrogeology of the oceanic lithosphere, Cambridge University Press, Cambridge, 706~pp., 2004. Davies, D. R., Davies, J. H., Hassan, O., Morgan, K., and Nithiarasu, P.: Adaptive finite element methods in geodynamics: Convection dominated mid-ocean ridge and subduction zone simulations, Int. J. Numer. Method. H., 18, 1015–1035, doi:10.1108/09615530810899079, 2008. Gosnold, W. D. and Panda, B.: The Global Heat Flow Database of The International Heat Flow Commission, http://www.und.edu/org/ihfc/index2.html (last access: 10 July 2007), 2002. Gradstein, F. M., Ogg, J. G., and Smith, A. G.: A Geologic Time scale 2004, Cambridge University Press, Cambridge, 610~pp., 2005. Hearn, P. J., Hare, T., Schruben, P., Sherrill, D., LaMar, C., and Tsushima, P.: Global GIS – Global Coverage DVD (USGS), American Geological Institute, Alexandria, Virginia, USA, 2003. Hernlund, J. W., Thomas, C., and Tackley, P. J.: A doubling of the post-perovskite phase boundary and structure of the Earth's lowermost mantle, Nature, 434, 882–886, 2005. Jaupart, C. and Mareschal, J.-C.: Constraints on crustal heat production from heat flow data, in: Treatise of Geochemistry, Vol 3, The Crust, edited by: Rudnick, R. L., Elsevier Science Publishers, Amsterdam, 65–84, 2003. Jaupart, C. and Mareschal, J.-C.: Heat flow and thermal structure of the lithosphere, in: Treatise on Geophysics, Vol. 6, edited by: Schubert, G., 217–252, Oxford, Elsevier Ltd., 2007. Jaupart, C., Labrosse, S., and Mareschal, J.-C.: Temperatures, heat and energy in the mantle of the Earth, in: Treatise on Geophysics, Vol. 7, Mantle Convection, edited by: Bercovici, D., Elsevier, 253–303, 2007. Kellogg, L. H., Hager, B. H., and van der Hilst, R. D.: Compositional stratification in the deep mantle, Science, 283, 1881–1884, 1999. Korenaga, J.: Energetics of mantle convection and the fate of fossil heat, Geophys. Res. Lett., 30, 1437, doi:10.1029/2002GL016179, 2003. Labrosse, S., Hernlund, J. W., and Coltice, N.: A crystallizing dense magma ocean at the base of the Earth's mantle, Nature, 450, 866–869, doi:10.1038/nature06355, 2007. Lay, T., Hernlund, J., Garnero, E., and Thorne, M.: A post-perovskite lens and D" heat flux beneath the central Pacific, Science, 314, 1272–1276, 2006. Lee, W. H. K. and Uyeda, S.: Review of heat flow data, in: Terrestrial Heat Flow, edited by: Lee, W. H. K., Geophys. Mono., 8, AGU, Washington, D.C., 87–190, 1965. Lyubetskaya, T. and Korenaga, J.: Chemical composition of Earth's primitive mantle and its variance: 2. Implications for global geodynamics, J. Geophys. Res., 112, B03212, doi:10.1029/2005JB004224, 2007a. Lyubetskaya, T. and Korenaga, J.: Chemical composition of Earth's primitive mantle and its variance: 1. Method and results, J. Geophys. Res., 112, B03211, doi:10.1029/2005JB004223, 2007b. Maule, C. F., Purucker, M. E., Olsen, N., and Mosegaard, K.: Heat flux anomalies in Antarctica revealed by satellite magnetic data, Science, 309, 464–467, 2005. McDonough, W. and Sun, S.: The composition of the Earth, Chem. Geol., 120, 223–253, 1995. Morgan, P.: Crustal radiogenic heat production and the selective survival of ancient continental crust, J. Geophys. Res., Supplement, 90, C561–C570, 1985. Nimmo, F., Price, G. D., Brodholt, J., and Gubbins, D.: The influence of potassium on core and geodynamo evolution, Geophys. J. Int., 156, 363–376, 2004. Palme, H. and O'Neill, H. S. C.: Composition of the Primitive Mantle, in: Treatise on Geochemistry, Vol. 2, The Mantle and Core, edited by: Carlson, R. W., Elsevier Scientific Publishers, Amsterdam, 1–38, 2003. Palmer, A. R.: Decade of North American Geology (DNAG), Geologic time scale, Geology, 11, 503–504, 1983. Parsons, B. and Sclater, J.: An analysis of the variation of ocean floor bathymetry and heat flow with age, J. Geophys. Res., 82, 803–827, 1977. Pollack, H. N., Hurter, S. J., and Johnson, J. R.: Heat-Flow from the Earths Interior – Analysis of the Global Data Set, Rev. Geophys., 31, 267–280, 1993. Polyak, D. G. and Smirnov, Y. A., Relation between terrestrial heat flow and tectonics of the continents, Geotectonics, 4, 205–213, 1968. Rudnick, R. and Fountain, D.: Nature and composition of the continental-crust – A lower crustal perspective, Rev. Geophys., 33, 267–309, 1995. Sclater, J. G., Jaupart, C., and Galson, D.: The heat flow through oceanic and continental crust and the heat loss of the Earth, Rev. Geophys. Space Phys., 18, 269–311, 1980. Shapiro, N. M. and Ritzwoller, M. H.: Inferring surface heat flux distributions guided by a global seismic model: particular application to Antarctica, Earth Planet. Sci. Lett., 223, 213–224, 2004. Sharpe, H. N. and Peltier, W. R.: Parameterized mantle convection and the Earth's thermal history, Geophys. Res. Lett., 5, 737–740, 1978. Slagstad, T., Balling, N., Elvebakk, H., Midttømme, K., Olesen, O., Olsen, L., and Pascal, C.: Heat-flow measurements in Late Palaeoproterozoic to Permian geological provinces in south and central Norway and a heat-flow map of Fennoscandia and the Norwegian-Greenland Sea, Tectonophysics, 473, 341–361, 2009. Sleep, N. H.: Hotspots and mantle plumes : some phenomenology, J. Geophys. Res., 95, 6715–6736, 1990. Stein, C. A. and Stein, S.: A model for the global variation in oceanic depth and heat flow with lithospheric age, Nature, 359, 123–129, 1992. Stein, C. A. and Von Herzen, R. P.: Potential effects of hydrothermal circulation and magmatism on heat flow at hotspot swells, in: Plates, Plumes and Planetary Processes, edited by: Foulger, G. R. and Jurdy, D. M., Geol. Soc. Am. Sp. Paper, 430, 261–274, doi:10.1130/2007.2430(13), 2007. Wei, M. and Sandwell, D.: Estimates of heat flow from Cenozoic seafloor using global depth and age data, Tectonophysics, 417, 325–335, 2006. Williams, D. L. and Von Herzen, R. P.: Heat loss from the Earth: new estimate, Geology, 2, 327–328, 1974.