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.

  • Letter
  • Published:

Strain accommodation by slow slip and dyking in a youthful continental rift, East Africa

Abstract

Continental rifts begin and develop through repeated episodes of faulting and magmatism, but strain partitioning between faulting and magmatism during discrete rifting episodes remains poorly documented. In highly evolved rifts, tensile stresses from far-field plate motions accumulate over decades before being released during relatively short time intervals by faulting and magmatic intrusions1,2,3. These rifting crises are rarely observed in thick lithosphere during the initial stages of rifting. Here we show that most of the strain during the July–August 2007 seismic crisis in the weakly extended Natron rift, Tanzania, was released aseismically. Deformation was achieved by slow slip on a normal fault that promoted subsequent dyke intrusion by stress unclamping. This event provides compelling evidence for strain accommodation by magma intrusion, in addition to slip along normal faults, during the initial stages of continental rifting and before significant crustal thinning.

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

Figure 1: Regional setting.
Figure 2: Earthquake locations from the local seismic network.
Figure 3: Interferograms and corresponding model results.
Figure 4: Slip/opening model.

Similar content being viewed by others

References

  1. Heki, K., Foulger, G., Julian, B. & Jahn, C. H. Plate dynamics near divergent boundaries: Geophysical implications of postrifting crustal deformation in NE Iceland. J. Geophys. Res. 98, 14279–14297 (1993)

    Article  Google Scholar 

  2. Cattin, R. et al. Numerical modelling of Quaternary deformation and post-rifting displacement in the Asal–Ghoubbet rift (Djibouti, Africa). Earth Planet. Sci. Lett. 239, 352–367 (2005)

    Article  ADS  CAS  Google Scholar 

  3. Wright, T. J. et al. Magma-maintained rift segmentation at continental rupture in the 2005 Afar dyking episode. Nature 442, 291–294 (2006)

    Article  ADS  CAS  Google Scholar 

  4. Baer, G., Hamiel, Y., Shamir, G. & Nof, R. Evolution of a magma-driven earthquake swarm and triggering of the nearby Oldoinyo Lengai eruption, as resolved by InSAR, ground observations, and elastic modelling, East African Rift, 2007. Earth Planet. Sci. Lett. 272 10.1016/j.epsl.2008.04.052 (2008)

  5. Ebinger, C. J., Poudjom Djomani, Y., Mbede, E., Foster, A. N. & Dawson, J. B. Rifting Archean lithosphere: Eyasi–Manyara–Natron rifts, East Africa. J. Geol. Soc. Lond. 154, 947–960 (1997)

    Article  CAS  Google Scholar 

  6. Stamps, D. S. et al. A kinematic model for the East African Rift. Geophys. Res. Letters 35 10.1029/ 2007GL032781 (2008)

  7. Birt, C. et al. The influence of pre-existing structures on the evolution of the southern Kenya rift valley – Evidence from seismic and gravity studies. Tectonophysics 278, 211–242 (1997)

    Article  ADS  Google Scholar 

  8. Green, W. V., Achauer, U. & Meyer, R. P. A three-dimensional seismic image of the crust and upper mantle beneath the Kenya rift. Nature 354, 199–203 (1991)

    Article  ADS  Google Scholar 

  9. Nyblade, A. A., Owens, T. J., Gurrola, H., Ritsema, J. & Langston, C. A. Seismic evidence for a deep upper mantle thermal anomaly beneath East Africa. Geology 7, 599–602 (2000)

    Article  ADS  Google Scholar 

  10. Vaughan, R. G., Kervyn, M., Realmuto, V., Abrams, M. & Hook, S. J. Satellite measurements of recent volcanic activity at Oldoinyo Lengai, Tanzania. J. Volcanol. Geotherm. Res. 173, 196–206 (2008)

    Article  ADS  CAS  Google Scholar 

  11. Dawson, J. B., Bowden, P. & Clark, G. C. Activity of the carbonatite volcano, Oldoinyo Lengai, 1966. Geol. Rundsch. 57, 865–879 (1968)

    Article  ADS  CAS  Google Scholar 

  12. Rubin, A. Dike-induced faulting and graben subsidence in volcanic rift zones. J. Geophys. Res. 92, 1839–1858 (1992)

    Article  ADS  Google Scholar 

  13. Okada, Y. Internal deformation due to shear and tensile faults in a half-space. Bull. Seismol. Soc. Am. 82, 1018–1040 (1992)

    Google Scholar 

  14. Mogi, K. Relations between the eruptions of various volcanoes and the deformations of the ground surfaces around them. Bull. Earthq. Res. Inst. Tokyo 36, 99–134 (1958)

    Google Scholar 

  15. Amelung, F., Yun, S.-H., Walter, T. R., Segall, P. & Kim, S. W. Stress control of deep rift intrusion at Mauna Loa volcano, Hawaii. Science 316, 1026–1030 (2007)

    Article  ADS  CAS  Google Scholar 

  16. Vauchez, A., Dineur, F. & Rudnick, R. Microstructure, texture and seismic anisotropy of the lithospheric mantle above a mantle plume: Insights from the Labait volcano xenoliths (Tanzania). Earth Planet. Sci. Lett. 232, 295–314 (2005)

    Article  ADS  CAS  Google Scholar 

  17. Ibs-von Seht, M., Blumenstein, S., Wagner, R., Hollnack, D. & Wohlenberg, J. Seismicity, seismotectonics and crustal structure of the southern Kenya Rift - new data from the Lake Magadi area. Geophys. J. Int. 146, 439–453 (2001)

    Article  ADS  Google Scholar 

  18. Tongue, J., Maguire, P. K. H. & Burton, P. An earthquake study in the Lake Baringo basin of the central Kenya Rift. Tectonophysics 236, 151–164 (1994)

    Article  ADS  Google Scholar 

  19. Nyblade, A. A., Birt, C., Langston, C. A., Owens, T. J. & Last, R. J. Seismic experiment reveals rifting of craton in Tanzania. Eos 77, 517–521 (1996)

    Article  ADS  Google Scholar 

  20. Buck, W. R. in Rheology and Deformation of the Lithosphere at Continental Margins (eds Karner, G. D., Taylor, B., Driscoll, N. & Kohlstedt, D.) 1–30 (Columbia Univ. Press, 2004)

    Book  Google Scholar 

  21. Lienert, B. R. E. & Havskov, J. A computer program for locating earthquakes both locally and globally. Seismol. Res. Lett. 66, 26–36 (1995)

    Article  Google Scholar 

  22. KRISP Working Party. Large-scale variation in lithospheric structure along and across the Kenya rift. Nature 354, 223–227 (1991)

    Article  Google Scholar 

  23. Massonnet, D. & Feigl, K. L. Radar interferometry and its application to changes in the Earth’s surface. Rev. Geophys. 36, 441–500 (1998)

    Article  ADS  Google Scholar 

  24. Chen, C. W. & Zebker, H. A. Two-dimensional phase unwrapping with use of statistical models for cost functions in nonlinear optimization. J. Opt. Soc. Am. A 18, 338–351 (2001)

    Article  ADS  CAS  Google Scholar 

  25. Cayol, V. & Cornet, F. H. Three-dimensional modeling of the 1983-1984 eruption at Piton de la Fournaise volcano, Réunion Island. J. Geophys. Res. 103, 18025–18037 (1998)

    Article  ADS  Google Scholar 

  26. Delaney, P. T. & McTigue, D. F. Volume of magma accumulation or withdrawal estimated from surface uplift or subsidence, with application to the 1960 collapse of Kilauea volcano. Bull. Volcanol. 56, 417–424 (1994)

    Article  ADS  Google Scholar 

  27. Johnson, D. J., Sigmundsson, F. & Delaney, P. T. Comment on “Volume of magma accumulation or withdrawal estimated from surface uplift or subsidence, with application to the 1960 collapse of Kilauea volcano” by P. T. Delaney and D. F. McTigue. Bull. Volcanol. 61, 491–493 (2000)

    Article  ADS  Google Scholar 

  28. Nishimura, T. Pressure recovery in magma due to bubble growth. Geophys. Res. Lett. 31 10.1029/2004GL019810 (2004)

    Article  Google Scholar 

Download references

Acknowledgements

Envisat/ASAR data were systematically programmed and acquired through the ESA Cat-1 project no. C1P.3224. Interferograms were computed using DORIS software (Delft University of Technology). Precise orbits were provided by the Delft Institute of Earth Observation and Space Systems and ESA. We thank the Tanzania Survey and Mapping Department for their support of the October field expedition and the Tanzania Commission for Science and Technology. We thank V. Cayol and Y. Fukushima for their contribution in analysing the ground deformations, F. Paganelli, J. Biggs and J. Keller for discussions and K. Feigl and F. Sigmundsson for their comments. We acknowledge support from the US National Science Foundation under grants EAR-0801801 and EAR-0538119, from the French INSU-CNRS DyETI programme and from the Belgian Science Policy under projects SAMAAV and Rukwa.

Author Contributions N.d’O., A.O. and F.K. planned the radar data acquisition and computed the interferograms; J.A., A.D., J.D., R.W.F. and J.P. designed the seismic experiment and collected and analysed the resulting data; D.D., A.S.M., B.S. and C.W. performed the field observations; E.S. and D.S.S. deployed the GPS equipment and processed the resulting data; C.E. provided tectonic context; E.C. performed the model calculations; E.C. and N.d’O. wrote the paper. All authors discussed the results and commented on the manuscript.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Eric Calais.

Supplementary information

Supplementary Information

This file contains Supplementary Tables 1 and 2 and Supplementary Figure 1 (PDF 808 kb)

PowerPoint slides

Rights and permissions

Reprints and permissions

About this article

Cite this article

Calais, E., d’Oreye, N., Albaric, J. et al. Strain accommodation by slow slip and dyking in a youthful continental rift, East Africa. Nature 456, 783–787 (2008). https://doi.org/10.1038/nature07478

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature07478

This article is cited by

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

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