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.

Open-system dynamics and mixing in magma mushes

Abstract

Magma dominantly exists in a slowly cooling crystal-rich or mushy state1,2,3. Yet, observations of complexly zoned crystals4, some formed in just one to ten years5,6,7,8,9, as well as time-transgressive crystal fabrics10 imply that magmas mix and transition rapidly from a locked crystal mush to a mobile and eruptable fluid5,6. Here we use a discrete-element numerical model that resolves crystal-scale granular interactions and fluid flow, to simulate the open-system dynamics of a magma mush. We find that when new magma is injected into a reservoir from below, the existing magma responds as a viscoplastic material: fault-like surfaces form around the edges of the new injection creating a central mixing bowl of magma that can be unlocked and become fluidized, allowing for complex mixing. We identify three distinct dynamic regimes that depend on the rate of magma injection. If the magma injection rate is slow, the intruded magma penetrates and spreads by porous media flow through the crystal mush. With increasing velocity, the intruded magma creates a stable cavity of fluidized magma that is isolated from the rest of the reservoir. At higher velocities still, the entire mixing bowl becomes fluidized. Circulation within the mixing bowl entrains crystals from the walls, bringing together crystals from different parts of the reservoir that may have experienced different physiochemical environments and leaving little melt unmixed. We conclude that both granular and fluid dynamics, when considered simultaneously, can explain observations of complex crystal fabrics and zoning observed in many magmatic systems.

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

Relevant articles

Open Access articles citing this article.

Access options

Buy article

Get time limited or full article access on ReadCube.

$32.00

All prices are NET prices.

Figure 1: Three time steps from the simulation of an open-system event in basaltic mush.
Figure 2: Crystal trajectories and zoning.
Figure 3: Crystal–crystal mixing efficiency.

References

  1. Hayes, B., Bédard, J. H. & Lissenberg, C. J. Olivine slurry replenishment and the development of igneous layering in a Franklin Sill, Victoria Island, Arctic Canada. J. Petrol. 56, 83–112 (2015).

    Article  Google Scholar 

  2. Cassidy, M., Edmonds, M., Watt, S. F. L., Palmer, M. R. & Gernon, T. M. Origin of basalts by hybridization in andesite-dominated arcs. J. Petrol. 56, 325–346 (2015).

    Article  Google Scholar 

  3. Ward, K. M., Zandt, G., Beck, S. L., Christensen, D. H. & McFarlin, H. Seismic imaging of the magmatic underpinnings beneath the Altiplano-Puna volcanic complex from the joint inversion of surface wave dispersion and receiver functions. Earth Planet. Sci. Lett. 404, 43–53 (2014).

    Article  Google Scholar 

  4. Kahl, M., Chakraborty, S., Costa, F. & Pompilio, M. Dynamic plumbing system beneath volcanoes revealed by kinetic modeling, and the connection to monitoring data: An example from Mt. Etna. Earth Planet. Sci. Lett. 308, 11–22 (2011).

    Article  Google Scholar 

  5. Cooper, K. M. & Kent, A. J. R. Rapid remobilization of magmatic crystals kept in cold storage. Nature 506, 480–483 (2014).

    Article  Google Scholar 

  6. Klemetti, E. W. & Clynne, M. A. Localized rejuvenation of a crystal mush recorded in zircon temporal and compositional variation at the Lassen volcanic center, northern California. PLoS ONE 9, e113157 (2014).

    Article  Google Scholar 

  7. Barboni, M. & Schoene, B. Short eruption window revealed by absolute crystal growth rates in a granitic magma. Nature Geosci. 7, 524–528 (2014).

    Article  Google Scholar 

  8. Passmore, E., Maclennan, J., Fitton, G. & Thordarson, T. Mush disaggregation in basaltic magma chambers: Evidence from the AD 1783 Laki eruption. J. Petrol. 53, 2593–2623 (2012).

    Article  Google Scholar 

  9. Costa, F., Coogan, L. A. & Chakraborty, S. The time scales of magma mixing and mingling involving primitive melts and melt–mush interaction at mid-ocean ridges. Contrib. Mineral. Petrol. 159, 371–387 (2010).

    Article  Google Scholar 

  10. Paterson, S. R. Magmatic tubes, pipes, troughs, diapirs, and plumes: Late-stage convective instabilities resulting in compositional diversity and permeable networks in crystal-rich magmas of the Tuolumne batholith, Sierra Nevada, California. Geosphere 5, 496–527 (2009).

    Article  Google Scholar 

  11. Burgisser, A. & Bergantz, G. W. A rapid mechanism to remobilize and homogenize highly crystalline magma bodies. Nature 471, 212–215 (2011).

    Article  Google Scholar 

  12. Huber, C., Bachmann, O. & Dufek, J. Thermo-mechanical reactivation of locked crystal mushes: Melting-induced internal fracturing and assimilation processes in magmas. Earth Planet. Sci. Lett. 304, 443–454 (2011).

    Article  Google Scholar 

  13. Zieg, M. J. & Marsh, B. D. Multiple reinjections and crystal-mush compaction in the beacon sill, McMurdo Dry Valleys, Antarctica. J. Petrol. 53, 2567–2591 (2012).

    Article  Google Scholar 

  14. Neave, D. A., Passmore, E., Maclennan, J., Fitton, G. & Thordarson, T. Crystal-melt relationships and the record of deep mixing and crystallization in the AD 1783 Laki eruption, Iceland. J. Petrol. 54, 1661–1690 (2013).

    Article  Google Scholar 

  15. Ehlmann, B. L. & Edwards, C. S. Mineralogy of the Martian surface. Annu. Rev. Earth Planet. Sci. 42, 291–315 (2014).

    Article  Google Scholar 

  16. Mehl, L. & Hirth, G. Plagioclase preferred orientation in layered mylonites: Evaluation of flow laws for the lower crust. J. Geophys. Res. 113, B05202 (2008).

    Article  Google Scholar 

  17. Paterson, S. R., Žák, J. & Janoušek, V. Growth of complex sheeted zones during recycling of older magmatic units into younger: Sawmill Canyon area, Tuolumne batholith, Sierra Nevada, California. J. Volcanol. Geotherm. Res. 177, 457–484 (2008).

    Article  Google Scholar 

  18. Bischofberger, I., Ramachandran, R. & Nagel, S. R. Fingering versus stability in the limit of zero interfacial tension. Nature Commun. 5, 5265 (2014).

    Article  Google Scholar 

  19. Huppert, H. E., Sparks, R. S. J., Whitehead, J. A. & Hallworth, M. A. Replenishment of magma chambers by light inputs. J. Geophys. Res. 91, 6113–6122 (1986).

    Article  Google Scholar 

  20. Dombrowski, C. et al. Coiling, entrainment, and hydrodynamic coupling of decelerated fluid jets. Phys. Rev. Lett. 95, 184501 (2005).

    Article  Google Scholar 

  21. Peng, Y. & Fan, L. T. Hydrodynamic characteristics of fluidization in liquid-solid tapered beds. Chem. Eng. Sci. 52, 2277–2290 (1997).

    Article  Google Scholar 

  22. Philippe, P. & Badiane, M. Localized fluidization in a granular medium. Phys. Rev. E 87, 042206 (2013).

    Google Scholar 

  23. Thomson, A. & Maclennan, J. The distribution of olivine compositions in Icelandic basalts and picrites. J. Petrol. 54, 745–768 (2013).

    Article  Google Scholar 

  24. Couch, S., Sparks, R. S. J. & Caroll, M. R. Mineral disequilibrium in lavas explained by convective self-mixing in open magma chambers. Nature 411, 1037–1039 (2001).

    Article  Google Scholar 

  25. Lacey, P. M. C. Developments in the theory of particle mixing. J. Appl. Chem. 4, 257–268 (1954).

    Article  Google Scholar 

  26. Wallace, G. S. & Bergantz, G. W. Reconciling heterogeneity in crystal zoning data: An application of shared characteristic diagrams at Chaos Crags, Lassen volcanic center, California. Contrib. Mineral. Petrol. 149, 98–112 (2005).

    Article  Google Scholar 

  27. Ruprecht, P., Bergantz, G. W. & Dufek, J. Modeling of gas-driven magmatic overturn: Tracking of phenocryst dispersal and gathering during magma mixing. Geochem. Geophys. Geosyst. 9, Q07017 (2008).

    Article  Google Scholar 

  28. Laumonier, M. et al. On the conditions of magma mixing and its bearing on andesite production in the crust. Nature Commun. 5, 5607 (2014).

    Article  Google Scholar 

  29. Cundall, P. A. & Strack, O. D. L. A discrete numerical model for granular assemblies. Géotechnique 29, 47–65 (1979).

    Article  Google Scholar 

  30. Garg, R., Galvin, J., Li, T. & Pannala, S. Documentation of Open-Source MFIX-DEM Software for Gas-Solids Flows (Department of Energy, National Energy Technology Laboratory, 2012); https://mfix.netl.doe.gov/download/mfix/mfix_current_documentation/dem_doc_2012-1.pdf

    Google Scholar 

Download references

Acknowledgements

Financial support was provided by National Science Foundation grants EAR-1049884 and EAR-1447266 to G.W.B. and DGE-1256082 to J.M.S. Access to computational facilities was provided by grant TG-EAR140013 to G.W.B. from the NSF-funded XSEDE consortium.

Author information

Authors and Affiliations

Authors

Contributions

G.W.B. wrote the manuscript and directed the numerical experiments. J.M.S. performed the simulations, created the figures and contributed to the Supplementary Information. A.B. contributed to the performance of the simulations. All authors participated in the workflow and revisions.

Corresponding author

Correspondence to G. W. Bergantz.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Information

Supplementary Information (PDF 988 kb)

Supplementary Information

Supplementary Information (AVI 184891 kb)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Bergantz, G., Schleicher, J. & Burgisser, A. Open-system dynamics and mixing in magma mushes. Nature Geosci 8, 793–796 (2015). https://doi.org/10.1038/ngeo2534

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/ngeo2534

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