Core–mantle boundary heat flow

ABSTRACT The Earth can be viewed as a massive heat engine, with various energy sources and sinks. Insights into its evolution can be obtained by quantifying the various energy contributions

in the context of the overall energy budget. Over the past decade, estimates of the heat flow across the core–mantle boundary, or across a chemical boundary layer above it, have generally

increased by a factor of 2 to 3. The current total heat flow at the Earth's surface — 46 ± 3 terawatts (1012 J s−1) — involves contributions from heat entering the mantle from the core,

as well as mantle cooling, radiogenic heating of the mantle from the decay of radioactive elements, and various minor processes such as tidal deformation, chemical segregation and thermal

contraction gravitational heating. The increased estimates of deep-mantle heat flow indicate a more prominent role for thermal plumes in mantle dynamics, more extensive partial melting of

the lowermost mantle in the past, and a more rapidly growing and younger inner core and/or presence of significant radiogenic material in the outer core or lowermost mantle as compared with

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Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS LONGITUDINAL STRUCTURE OF EARTH’S MAGNETIC FIELD CONTROLLED BY LOWER MANTLE HEAT FLOW Article 16 March 2023 WEAK MAGNETIC

FIELD CHANGES OVER THE PACIFIC DUE TO HIGH CONDUCTANCE IN LOWERMOST MANTLE Article 29 June 2020 SUSTAINING EARTH’S MAGNETIC DYNAMO Article 10 March 2022 REFERENCES * Pollack, H. N., Hurter,

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Planet. Sci. Lett._ (in the press). Download references ACKNOWLEDGEMENTS We thank F. Nimmo and S. Labrosse for preprints, and F. Nimmo, Richard Holme and Bill McDonough for their comments on

the manuscript. T.L.'s research on the deep Earth is supported by the NSF. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Earth and Planetary Sciences Department, University of

California, Santa Cruz, 91125, California, USA Thorne Lay * Earth and Ocean Sciences, University of British Columbia, Vancouver, V6T 1Z4, British Columbia, Canada John Hernlund * Department

of Geophysical Sciences, University of Chicago, Chicago, 60637, Illinois, USA Bruce A. Buffett Authors * Thorne Lay View author publications You can also search for this author inPubMed 

Google Scholar * John Hernlund View author publications You can also search for this author inPubMed Google Scholar * Bruce A. Buffett View author publications You can also search for this

author inPubMed Google Scholar CONTRIBUTIONS T.L., J.H. and B.A.B. contributed equally to the writing, data analysis and ideas in this paper. CORRESPONDING AUTHOR Correspondence to Thorne

Lay. RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Lay, T., Hernlund, J. & Buffett, B. Core–mantle boundary heat flow. _Nature Geosci_ 1, 25–32

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