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.

  • Article
  • Published:

Thermochemical structure and evolution of cratonic lithosphere in central and southern Africa

An Author Correction to this article was published on 16 January 2023

This article has been updated

Abstract

The thermochemical structure of the subcontinental mantle holds information on its origin and evolution that can inform energy and mineral exploration strategies, natural hazard mitigation and evolutionary models of Earth. However, imaging the fine-scale thermochemical structure of continental lithosphere remains a major challenge. Here we combine multiple land and satellite datasets via thermodynamically constrained inversions to obtain a high-resolution thermochemical model of central and southern Africa. Results reveal diverse structures and compositions for cratons, indicating distinct evolutions and responses to geodynamic processes. While much of the Kaapvaal lithosphere retained its cratonic features, the western Angolan–Kasai Shield and the Rehoboth Block have lost their cratonic keels. The lithosphere of the Congo Craton has been affected by metasomatism, increasing its density and inducing its conspicuous low-topography, geoid and magnetic anomalies. Our results reconcile mantle structure with the causes and location of volcanism within and around the Tanzanian Craton, whereas the absence of volcanism towards the north is due to local asthenospheric downwellings, not to a previously proposed lithospheric root connecting with the Congo Craton. Our study offers improved integration of mantle structure, magmatism and the evolution and destruction of cratonic lithosphere, and lays the groundwork for future lithospheric evolutionary models and exploration frameworks for Earth and other terrestrial planets.

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

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Tectonic and thermochemical structures in central and southern Africa.
Fig. 2: Three-dimensional renderings of the thermal structure beneath the study area.
Fig. 3: Hot-spot tracks and location of kimberlitic and carbonatitic volcanism superimposed on lithospheric structure.

Similar content being viewed by others

Data availability

The data that support the findings of this study are available from the community data repository Figshare at https://doi.org/10.6084/m9.figshare.19322180.

Code availability

The codes used to perform the inversions are available from the corresponding author upon request or via https://www.juanafonso.com/.

Change history

References

  1. Griffin, W., Begg, G. & O’Reilly, S. Continental-root control on the genesis of magmatic ore deposits. Nat. Geosci. 6, 905–910 (2013).

    Article  Google Scholar 

  2. Holwell, D. A. et al. A metasomatized lithospheric mantle control on the metallogenic signature of post-subduction magmatism. Nat. Commun. 10, 3511 (2019).

    Article  Google Scholar 

  3. Craig, T. J., Jackson, J. A., Priestley, K. & McKenzie, D. Earthquake distribution patterns in Africa: their relationship to variations in lithospheric and geological structure, and their rheological implications. Geophys. J. Int. 185, 403–434 (2011).

    Article  Google Scholar 

  4. Hoggard, M. J. et al. Global distribution of sediment-hosted metals controlled by craton edge stability. Nat. Geosci. 13, 504–510 (2020).

    Article  Google Scholar 

  5. Begg, G. G., Hronsky, J. M. A., Griffin, W. L. & O’Reilly, S. Y. in Processes and Ore Deposits of Ultramafic-Mafic Magmas Through Space and Time (eds Mondal, S. K. & Griffin, W. L.) 1–46 (Elsevier, 2018).

  6. Heinson, G. et al. The crustal geophysical signature of a world-class magmatic mineral system. Sci. Rep. 8, 10608 (2018).

    Article  Google Scholar 

  7. Begg, G. et al. Lithospheric, cratonic, and geodynamic setting of Ni–Cu–PGE sulfide deposits. Econ. Geol. 105, 1057–1070 (2010).

    Article  Google Scholar 

  8. Schutt, D. L. & Lesher, C. E. Effects of melt depletion on the density and seismic velocity of garnet and spinel lherzolite. J. Geophys. Res. 111, B05401 (2006).

    Google Scholar 

  9. O’Reilly, S. Y. & Griffin, W. L. Imaging chemical and thermal heterogeneity in the sub-continental lithospheric mantle with garnets and xenoliths: geophysical implications. Tectonophysics 416, 289–309 (2006).

    Article  Google Scholar 

  10. Afonso, J. C. et al. 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, 606–618 (2010).

    Article  Google Scholar 

  11. Afonso, J. C. et al. 3-D multi-observable probabilistic inversion for the compositional and thermal structure of the lithosphere and upper mantle. I: A priori petrological information and geophysical observables. J. Geophys. Res. Solid Earth 118, 2586–2617 (2013).

    Article  Google Scholar 

  12. Afonso, J. C., Fullea, J., Yang, Y., Connolly, J. A. D. & Jones, A. G. 3-D 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. Solid Earth 118, 1650–1676 (2013).

    Article  Google Scholar 

  13. Afonso, J. C. et al. 3-D multiobservable probabilistic inversion for the compositional and thermal structure of the lithosphere and upper mantle: III. Thermochemical tomography in the Western-Central US. J. Geophys. Res. Solid Earth 121, 7337–7370 (2016).

    Article  Google Scholar 

  14. Hu, J. et al. Modification of the Western Gondwana Craton by plume–lithosphere interaction. Nat. Geosci. 11, 203–210 (2018).

    Article  Google Scholar 

  15. Grand, S. Mantle shear-wave tomography and the fate of subducted slabs. Phil. Trans. R. Soc. A 360, 2475–2491 (2002).

    Article  Google Scholar 

  16. Ritsema, J. & Van Heijst, H. J. Seismic imaging of structural heterogeneity in Earth’s mantle: evidence for large-scale mantle flow. Sci. Prog. 83, 243–259 (2000).

    Google Scholar 

  17. Fishwick, S. Surface wave tomography: imaging of the lithosphere–asthenosphere boundary beneath central and southern Africa? Lithos 120, 63–73 (2010).

    Article  Google Scholar 

  18. Celli, N. L. et al. African cratonic lithosphere carved by mantle plumes. Nat. Commun. 11, 92 (2020).

    Article  Google Scholar 

  19. Torsvik, T. H., Rousse, S., Labails, C. & Smethurst, M. A. A new scheme for the opening of the South Atlantic Ocean and the dissection of an Aptian salt basin. Geophys. J. Int. 177, 1315–1333 (2009).

    Article  Google Scholar 

  20. Yuan, X. et al. Seismic structure of the lithosphere beneath NW Namibia: impact of the Tristan da Cunha mantle plume. Geochem. Geophys. Geosyst. 18, 125–141 (2017).

    Article  Google Scholar 

  21. Jelsma, H. et al. Kimberlites from central Angola: a case study of exploration findings. In Proc. 10th International Kimberlite Conference (eds Pearson, G. D. et al.) 173–190 (Springer, 2012).

  22. Giuliani, A. et al. Southwestern Africa on the burner: Pleistocene carbonatite volcanism linked to deep mantle upwelling in Angola. Geology 45, 971–974 (2017).

    Article  Google Scholar 

  23. Hopper, E. et al. Preferential localized thinning of lithospheric mantle in the melt-poor Malawi Rift. Nat. Geosci. 13, 584–589 (2020).

    Article  Google Scholar 

  24. Hoal, K. E. O. Samples of Proterozoic Fe-enriched mantle from the Premier kimberlite. Lithos 71, 259–272 (2003).

    Article  Google Scholar 

  25. Kobussen, A. F., Griffin, W. L. & O’Reilly, S. Y. Cretaceous thermo-chemical modification of the Kaapvaal cratonic lithosphere, South Africa. Lithos 112, 886–895 (2009).

    Article  Google Scholar 

  26. Fritz, H. et al. Orogen styles in the East African Orogen: a review of the Neoproterozoic to Cambrian tectonic evolution. J. Afr. Earth Sci. 86, 65–106 (2013).

    Article  Google Scholar 

  27. Eaton, D. W. et al. The elusive lithosphere–asthenosphere boundary (LAB) beneath cratons. Lithos 109, 1–22 (2009).

    Article  Google Scholar 

  28. Link, K. et al. Continuous cratonic crust between the Congo and Tanzania blocks in western Uganda. Int. J. Earth Sci. 99, 1559–1573 (2010).

    Article  Google Scholar 

  29. Rosenthal, A., Foley, S. F., Pearson, D. G., Nowell, G. M. & Tappe, S. Magmatic evolution at the propagating tip of a continental rift—a geochemical study of primitive alkaline volcanic rocks of the western branch of the East African Rift. Earth Planet. Sci. Lett. 284, 236–248 (2009).

    Article  Google Scholar 

  30. Dawson, J. B. Quaternary kimberlitic volcanism on the Tanzania Craton. Contrib. Mineral. Petrol. 116, 473–485 (1994).

    Article  Google Scholar 

  31. Alvarez, P. Evidence for a Neoproterozoic carbonate ramp on the northern edge of the Central Africa Craton: relations with late Proterozoic intracratonic troughs. Geol. Rundsch. 84, 636–648 (1995).

    Article  Google Scholar 

  32. Crosby, A. G., Fishwick, S. & White, N. Structure and evolution of the intracratonic Congo Basin. Geochem. Geophys. Geosyst. 11, Q06010 (2010).

    Article  Google Scholar 

  33. Kadima, E., Delvaux, D., Sebagenzi, S. N., Tack, L. & Kabeya, S. M. Structure and geological history of the Congo Basin: an integrated interpretation of gravity, magnetic and reflection seismic data. Basin Res. 23, 499–527 (2011).

    Article  Google Scholar 

  34. Hartley, R. W. & Allen, P. A. Interior cratonic basins of Africa: relation to continental break-up and role of mantle convection. Basin Res. 6, 95–113 (1994).

    Article  Google Scholar 

  35. Downey, N. J. & Gurnis, M. Instantaneous dynamics of the cratonic Congo Basin. J. Geophys. Res. 114, B06401 (2009).

    Google Scholar 

  36. Forte, A. M. et al. Joint seismic–geodynamic–mineral physical modeling of African geodynamics: a reconciliation of deep mantle convection with surface geophysical constraints. Earth Planet. Sci. Lett. 295, 329–341 (2010).

    Article  Google Scholar 

  37. Griffin, W. L., Graham, S., O’Reilly, S. Y. & Pearson, N. J. Lithosphere evolution beneath the Kaapvaal Craton. Re–Os systematics of sulfides in mantle-derived peridotites. Chem. Geol. 208, 89–118 (2004).

    Article  Google Scholar 

  38. Capitanio, F. A., Nebel, O. & Cawood, P. A. Thermochemical lithosphere differentiation and the origin of cratonic mantle. Nature 588, 89–94 (2020).

    Article  Google Scholar 

  39. Dang, Z. et al. Weak orogenic lithosphere guides the pattern of plume-triggered supercontinent break-up. Commun. Earth Environ. 1, 51 (2020).

    Article  Google Scholar 

  40. Cooper, C. M., Farrington, R. J. & Miller, M. S. On the destructive tendencies of cratons. Geology 49, 195–200 (2020).

    Article  Google Scholar 

  41. Laske, G., Master, G., Ma, Z. & Pasyanos, M. Update on CRUST1.0—A 1-degree global model of Earth’s crust. Geophys. Res. Abstr. 15, EGU2013–2658 (2013).

    Google Scholar 

  42. Afonso, J. C., Salajegheh, F., Szwillus, W., Ebbing, J. & Gaina, C. A global reference model of the lithosphere and upper mantle from joint inversion and analysis of multiple data set. Geophys. J. Int. 217, 1602–1628 (2019).

    Article  Google Scholar 

  43. Amante, C. & Eakins, B. W. ETOPO11 Arc-Minute Global Relief Model: Procedures, Data Sources and Analysis NOAA Technical Memorandum NESDIS NGDC-24 (National Geophysical Data Center, NOAA, 2009); https://doi.org/10.7289/V5C8276M

  44. Goutourbe, B., Poort, J., Lucazeau, F. & Raillard, S. Global heat flow trends resolved from multiple geological and geophysical proxies. Geophys. J. Int. 187, 1405–1419 (2011).

    Article  Google Scholar 

  45. Bonvalot, S. et al. World Gravity Map (International Gravimetric Bureau, 2012).

  46. Kvas, A. et al. ITSG-Grace2018: overview and evaluation of a new GRACE-only gravity field time series. J. Geophys. Res. Solid Earth 124, 9332–9344 (2019).

    Article  Google Scholar 

  47. Schaeffer, A. J. & Lebedev, S. Global shear speed structure of the upper mantle and transition zone. Geophys. J. Int. 194, 417–449 (2013).

    Article  Google Scholar 

  48. Yang, Y., Li, A. & Ritzwoller, M. H. Crustal and uppermost mantle structure in southern Africa revealed from ambient noise and teleseismic tomography. Geophys. J. Int. 174, 235–248 (2008).

    Article  Google Scholar 

  49. Adams, A. N. et al. Lithospheric instability and the source of the Cameroon Volcanic Line: evidence from Rayleigh wave phase velocity tomography. J. Geophys. Res. Solid Earth 120, 1708–1727 (2015).

    Article  Google Scholar 

  50. O’Donnell, J. P., Adams, A., Nyblade, A. A., Mulibo, G. D. & Tugume, F. The uppermost mantle shear wave velocity structure of eastern Africa from Rayleigh wave tomography: constraints on rift evolution. Geophys. J. Int. 194, 961–978 (2013).

    Article  Google Scholar 

  51. Herrmann, R. B. Computer Programs in Seismology v.3.30 http://www.eas.slu.edu/eqc/eqcsoftware.html (Saint Louis University, 2002).

  52. Dalton, C. A., Ekström, G. & Dziewonski, A. M. The global attenuation structure of the upper mantle. J. Geophys. Res. 113, B09303 (2008).

    Google Scholar 

  53. Simmons, N. A., Forte, A. M., Boschi, L. & Grand, S. P. GyPSuM: a joint tomographic model of mantle density and seismic wave speeds. J. Geophys. Res. 115, B12310 (2010).

    Article  Google Scholar 

  54. Schimmel, M. & Gallart, J. Frequency-dependent phase coherence for noise suppression in seismic array data. J. Geophys. Res. Solid Earth 112, B04303 (2007).

    Article  Google Scholar 

  55. Li, G., Niu, F., Yang, Y. & Xie, J. An investigation of time-frequency domain phase-weighed stacking and its application to phase-velocity extraction from ambient noise’s empirical Green’s functions. Geophys. J. Int. 212, 1143–1156 (2018).

    Article  Google Scholar 

  56. Sebai, A., Stutzmann, E., Montagner, J.-P., Sicilia, D. & Beucler, E. Anisotropic structure of the African upper mantle from Rayleigh and Love wave tomography. Phys. Earth Planet. Inter. 155, 48–62 (2006).

    Article  Google Scholar 

  57. Ravenna, M., Lebedev, S., Fullea, J. & Adam, J. M.-C. Shear-wave velocity structure of southern Africa’s lithosphere: variations in the thickness and composition of cratons and their effect on topography. Geochem. Geophys. Geosyst. 19, 1499–1518 (2018).

  58. Haario, H., Laine, M., Mira, A. & Saksman, E. DRAM: efficient adaptive MCMC. Stat. Comput. 16, 339–354 (2006).

    Article  Google Scholar 

  59. Liu, J. S., Liang, F. & Wong, W. H. The multiple-try method and local optimization in Metropolis sampling. J. Am. Stat. Assoc. 95, 121–134 (2000).

    Article  Google Scholar 

  60. Connolly, J. A. The geodynamic equation of state: what and how. Geochem. Geophys. Geosyst. 10, Q10014 (2009).

    Article  Google Scholar 

  61. Stixrude, L. & Lithgow-Bertelloni, C. Thermodynamics of mantle minerals-II. Phase equilibria. Geophys. J. Int. 184, 1180–1213 (2011).

    Article  Google Scholar 

  62. Brocher, T. M. Empirical relations between elastic wavespeeds and density in the Earth’s crust. Bull. Seismol. Soc. Am. 95, 2081–2092 (2005).

    Article  Google Scholar 

Download references

Acknowledgements

We thank S. Lebedev for valuable suggestions. We also acknowledge the AfricaArray programme and all its members. W.B.-M. and J.C.A. acknowledge funding from ARC Grant DP160103502, ARC CE110001017, ARC Linkage Grant LP170100233 and Macquarie University DVCR co-funding scheme. This is contribution 1681 from the ARC Centre of Excellence for Core to Crust Fluid Systems (www.ccfs.mq.edu.au) and 1480 in the GEMOC Key Centre (http://www.gemoc.mq.edu.au).

Author information

Authors and Affiliations

Authors

Contributions

J.C.A., N.J., A.M. and W.B.-M. conceived the project. W.B.-M., J.C.A., F.S. and I.F. performed the inversions and processed all datasets and results. All authors analysed the results and contributed to writing the manuscript.

Corresponding author

Correspondence to Juan C. Afonso.

Ethics declarations

Competing interests

The authors declare no competing interests.

Peer review

Peer review information

Nature Geoscience thanks Sergei Lebedev, Atalay Ayele and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Primary Handling Editor: Rebecca Neely, in collaboration with the Nature Geoscience team.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Text, Discussion and Figs. 1–29.

Supplementary Video 1

Supplementary video S1 is a video displaying a sequence of 2,500 random realizations of LAB depth from the full posterior distribution at a nominal resolution of 2° × 2°.

Supplementary Video 2

Supplementary video S2 is a video displaying a sequence of 2,500 random realizations of average lithospheric Mg# from the full posterior distribution at a nominal resolution of 2° × 2°.

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Afonso, J.C., Ben-Mansour, W., O’Reilly, S.Y. et al. Thermochemical structure and evolution of cratonic lithosphere in central and southern Africa. Nat. Geosci. 15, 405–410 (2022). https://doi.org/10.1038/s41561-022-00929-y

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41561-022-00929-y

This article is cited by

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