Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Geophysics

Hot blanket in Earth's deep crust

Nature volume 458, pages 292–293 (2009)Cite this article

Studies of rocks from Earth's crust suggest that the lower crust is a good thermal insulator. The knock-on effects of this finding are many — one being the crust's increased potential to generate more magma.

We know little about the temperature of the deepest parts of Earth's continental crust, which can be 30–40 kilometres below the surface. We cannot measure temperature directly beyond a few kilometres down, at the bottom of deep mines or drill holes. Yet temperature governs many geological processes, including the generation of magmas through the melting of rocks in the lower crust and the mechanism by which rocks deform. In the crust, heat from the underlying mantle is mainly transported by conduction. The efficiency of the process is regulated by the crust's thermal conductivity: a high conductivity results in efficient heat flow and a relatively low temperature at the base of the crust; conversely, a low conductivity results in poor conduction of heat and a high temperature at the base of the crust — the lower crust is a good insulator and thus acts as a blanket over the mantle.

This is a preview of subscription content, access via your institution

Access options

Buy article

Get time limited or full article access on ReadCube.

$32.00

Buy

All prices are NET prices.

Figure 1: Thermal conductivity and temperature in Earth's crust.
Figure 2: Implications of a lower crust that is warmer than expected.

References

  1. Whittington, A. G., Hofmeister, A. M. & Nabelek, P. I. Nature 458, 319–321 (2009).

    Article  CAS  ADS  Google Scholar 

  2. Regenauer-Lieb, K. et al. Nature 442, 67–70 (2006).

    Article  CAS  ADS  Google Scholar 

  3. Harrison, T. M., Grove, M., Lovera, O. M. & Catlos, E. J. J. Geophys. Res. 103, 27017–27032 (1998).

    Article  ADS  Google Scholar 

  4. Beaumont, C. et al. Nature 414, 738–742 (2001).

    Article  CAS  ADS  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Jean Braun is at the Géosciences Rennes CNRS UMR 6118, Université de Rennes 1, Rennes F-35042, France. jean.braun@univ-rennes1.fr,

    Jean Braun

Authors
  1. Jean Braun
    View author publications

    You can also search for this author in PubMed Google Scholar

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Braun, J. Hot blanket in Earth's deep crust. Nature 458, 292–293 (2009). https://doi.org/10.1038/458292a

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/458292a

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing