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Fine-scale segmentation of the crustal magma reservoir beneath the East Pacific Rise


The global mid-ocean ridge is segmented in its seafloor morphology and magmatic systems, but the origin of and relationships between this tectonic and magmatic segmentation are poorly understood1,2,3,4,5. At fast-spreading ridges, tectonic segmentation is observed on a fine scale2,4,6,7,8, but it is unclear whether this partitioning also occurs in the magmatic system. Fine-scale tectonic segmentation could have a deep origin, arising from the distribution of upwelling mantle melt, or a shallow origin, linked to offset intruding dikes from long, more continuous crustal reservoirs2,9. Here we use seismic reflection data from the fast-spreading East Pacific Rise, between 8° 20′ N and 10° 10′ N, which includes a unique area where two documented volcanic eruptions have occurred10,11,12,13,14,15, to image the crustal magma bodies in high resolution. We find that the magma reservoirs form 5- to 15-km-long segments that coincide with the fine-scale tectonic segmentation at the seafloor and that three lens segments fed the recent eruptions. Transitions in composition, volume and morphology of erupted lavas coincide with disruptions in the lens that define magmatic segments. We conclude that eruptions at the East Pacific Rise are associated with the vertical ascent of magma from lenses that are mostly physically isolated, leading to the eruption of distinct lavas at the surface that coincide with fine-scale tectonic segmentation.

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Figure 1: Segmentation in seafloor structure, AML, lava geochemistry and eruption volume along the EPR 9° 35′–10° 06′ N.
Figure 2: Comparison of magma lens and bathymetric segmentation along the EPR 8° 20′–10° 10′ N.
Figure 3: Schematic representation of EPR magmatic system and 2005–2006 eruption.


  1. Langmuir, C. H., Bender, J. F. & Batiza, R. Petrological and tectonic segmentation of the East Pacific Rise, 5° 30′–14° 30′ N. Nature 322, 422–429 (1986).

    Article  Google Scholar 

  2. Macdonald, K. C. et al. A new view of the mid-ocean ridge from the behaviour of ridge-axis discontinuities. Nature 335, 217–225 (1988).

    Article  Google Scholar 

  3. Smith, M. C. et al. Magmatic processes and segmentation at a fast spreading mid-ocean ridge: Detailed investigation of an axial discontinuity on the East Pacific Rise crest at 9° 37′ N. Geochem. Geophys. Geosyst. 2, 1040 (2001).

    Article  Google Scholar 

  4. White, S. M. et al. Correlation between volcanic and tectonic segmentation of fast-spreading ridges: Evidence from volcanic structures and lava flow morphology on the East Pacific Rise at 9°–10° N. J. Geophys. Res. 107, 2173 (2002).

    Article  Google Scholar 

  5. Toomey, D. R., Jousselin, D., Dunn, R. A., Wilcock, W. S. D. & Detrick, R. S. Skew of mantle upwelling beneath the East Pacific Rise governs segmentation. Nature 446, 409–414 (2007).

    Article  Google Scholar 

  6. Haymon, R. M. et al. Hydrothermal vent distribution along the East Pacific Rise crest (9° 09′–9° 54′ N) and its relationship to magmatic and tectonic processes on fast spreading Mid-Ocean Ridges. Earth Planet. Sci. Lett. 104, 513–534 (1991).

    Article  Google Scholar 

  7. Fornari, D. J., Haymon, R. M., Perfit, M. R., Gregg, T. K. P. & Edwards, M. H. Axial summit trough of the East Pacific Rise 9°–10° N: Geological characteristics and evolution of the axial zone on fast spreading mid-ocean ridges. J. Geophys. Res. 103, 9827–9855 (1998).

    Article  Google Scholar 

  8. White, S. M., Haymon, R. M. & Carbotte, S. A new view of ridge segmentation and near-axis volcanism at the East Pacific Rise, 8°–12° N, from EM300 multibeam bathymetry. Geochem. Geophys. Geosyst. 7, Q12O05 (2006).

    Google Scholar 

  9. Dunn, R. A., Toomey, D. R. & Solomon, S. C. Three-dimensional seismic structure and physical properties of the crust and shallow mantle beneath the East Pacific Rise at 9° 30′ N. J. Geophys. Res. 105, 23537–23555 (2000).

    Article  Google Scholar 

  10. Haymon, R. M. et al. Volcanic eruption of the mid-ocean ridge along the East Pacific Rise crest at 9° 45–52′ N: Direct submersible observations of seafloor phenomena associated with an eruption event in April, 1991. Earth Planet. Sci. Lett. 119, 85–101 (1993).

    Article  Google Scholar 

  11. Tolstoy, M. et al. A sea-floor spreading event captured by seismometers. Science 314, 1920–1922 (2006).

    Article  Google Scholar 

  12. Soule, S. A., Fornari, D. J., Perfit, M. R. & Rubin, K. H. New insights into mid-ocean ridge volcanic processes from the 2005–2006 eruption of the East Pacific Rise, 9° 46′ N–9° 56′ N. Geology 35, 1079–1082 (2007).

    Article  Google Scholar 

  13. Goss, A. R. et al. Geochemistry of lavas from the 2005–2006 eruption at the East Pacific Rise, 9° 46′ N–9° 56′ N: Implications for ridge crest plumbing and decadal changes in magma chamber compositions. Geochem. Geophys. Geosyst. 11, Q05T09 (2010).

    Article  Google Scholar 

  14. Perfit, M. et al. Lava geochemistry as a probe into crustal formation at the East Pacific Rise. Oceanography 25, 21–24 (2012).

    Article  Google Scholar 

  15. Rubin, K. H. et al. Volcanic eruptions in the deep sea. Oceanography 25, 142–157 (2012).

    Article  Google Scholar 

  16. Soule, S. A., Escartı´n, J. & Fornari, D. J. A record of eruption and intrusion at a fast spreading ridge axis: Axial summit trough of the East Pacific Rise 9–10° N. Geochem. Geophys. Geosyst. 10, Q10T07 (2009).

    Article  Google Scholar 

  17. Kent, G. M., Harding, A. J. & Orcutt, J. A. Distribution of magma beneath the East Pacific Rise between the Clipperton transform and the 9° 17′ N deval from forward modeling of common depth point data. J. Geophys. Res. 98, 13945–13969 (1993).

    Article  Google Scholar 

  18. Carton, H. D. et al. Three-dimensional seismic reflection images of axial melt lens and seismic layer 2A between 9° 42′ N and 9° 57′ N on the East Pacific Rise. EOS Trans. AGU abstr. OS21C-1514 (2010).

  19. Kent, G. M. et al. Evidence from three-dimensional seismic reflectivity images for enhanced melt supply beneath mid-ocean ridge discontinuities. Nature 406, 614–618 (2000).

    Article  Google Scholar 

  20. Sims, K. W. W. et al. Aberrant youth: Chemical and isotopic constraints on the origin of off-axis lavas from the East Pacific Rise, 9°–10° N. Geochem. Geophys. Geosyst. 4, 8621 (2003).

    Article  Google Scholar 

  21. Fundis, A. T., Soule, S. A., Fornari, D. J. & Perfit, M. R. Paving the seafloor: Volcanic emplacement processes during the 2005–2006 eruptions at the fast spreading East Pacific Rise, 9° 50′ N. Geochem. Geophys. Geosyst. 11, Q08024 (2010).

    Article  Google Scholar 

  22. Varga, R. J., Horst, A. J., Gee, J. S. & Karson, J. A. Direct evidence from anisotropy of magnetic susceptibility for lateral melt migration at superfast spreading centers. Geochem. Geophys. Geosyst. 9, Q08008 (2008).

    Article  Google Scholar 

  23. Stewart, M. A., Karson, J. A. & Klein, E. M. Four-dimensional upper crustal construction at fast-spreading mid-ocean ridges: A perspective from an upper crustal cross-section at the Hess Deep Rift. J. Volcanol. Geotherm. Res. 144, 287–309 (2005).

    Article  Google Scholar 

  24. Bergmanis, E. C., Sinton, J. & Rubin, K. H. Recent eruptive history and magma reservoir dynamics on the southern East Pacific Rise at 17° 30′ S. Geochem. Geophys. Geosyst. 10, Q12O06 (2007).

    Google Scholar 

  25. Kelemen, P. B., Koga, K. & Shimizu, N. Geochemistry of gabbro sills in the crust-mantle transition zone of the Oman ophiolite: Implications for the origin of the oceanic lower crust. Earth Planet Sci. Lett. 146, 475–488 (1997).

    Article  Google Scholar 

  26. Natland, J. H. & Dick, H. J. B. Paired melt lenses at the East Pacific Rise and the pattern of melt flow through the gabbroic layer at a fast-spreading ridge. Lithos 112, 73–86 (2009).

    Article  Google Scholar 

  27. Mutter, J. C. et al. Seismic images of active magma systems beneath the East Pacific Rise between 17° 05′ and 17° 35′ S. Science 21, 391–395 (1995).

    Article  Google Scholar 

  28. Coogan, L. A., Mitchell, N. C. & O’Hara, M. J. Roof assimilation at fast-spreading ridges: An investigation combining geophysical, geochemical and field evidence. J. Geophys. Res. 108, 2002 (2003).

    Article  Google Scholar 

  29. Fontaine, F. J., Olive, J-A., Cannat, M., Escartı´n, J. & Perol, T. Hydrothermally-induced melt lens cooling and segmentation along the axis of fast- and intermediate-spreading centers. Geophys. Res. Lett. 38, L14307 (2011).

    Article  Google Scholar 

  30. Von Damm, K. L. in Mid-Ocean Ridges: Hydrothermal Interactions Between the Lithosphere and Ocean (ed. German, C. R.) 285–304 (AGU Geophys. Mono., Vol. 148, American Geophysical Union, 2004).

    Google Scholar 

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We thank Captain M. Landow, crew, and technical staff led by R. Steinhaus for the success of RV M.G. Langseth cruise MGL0812. We thank I. Grevemeyer for comments, R. Waters for assistance with the geochemical data, and K. C. Macdonald, R. M. Haymon and R. Buck for helpful discussions. This research was financially supported by NSF OCE0327872 to S.M.C. and J.C.M., OCE0327885 to J.P.C., and OCE0138088 to M.R.P.

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All authors (except M.R.P. and S.H.) participated in the MCS field experiment. M.M. carried out the MCS data processing, S.M.C. and M.M. interpreted the data. M.R.P. contributed geochemical data and interpretation. S.M.C. wrote the paper with contributions from all co-authors.

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Correspondence to Suzanne M. Carbotte.

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Carbotte, S., Marjanović, M., Carton, H. et al. Fine-scale segmentation of the crustal magma reservoir beneath the East Pacific Rise. Nature Geosci 6, 866–870 (2013).

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