Magma supply from the lower crust is often proposed as a trigger mechanism for volcanic eruptions. The timescales over which magma can be transported from the deepest parts of volcanic systems are, however, poorly constrained. This uncertainty poses problems for the construction of physical models and for assessment of volcanic hazards. Here, we combined geothermobarometry with Bayesian inversion diffusion chronometry on primitive olivine crystals from the Borgarhraun eruption, northern Iceland. We find that magma took about 10 days to ascend from near-Moho storage at 24 km depth before its eruption, and therefore present timescales for transcrustal magma transport on the global spreading ridge system. Our results reveal a rapid connection between the lower and upper crust with melt transport rates of 0.02 to 0.1 m s−1, which are consistent with the propagation rates observed in seismic swarms in the Icelandic lower crust. Monitoring of such events using surface CO2 fluxes may provide one of the earliest indicators that an eruption is imminent. At the high transport rates and low CO2 contents estimated for the Borgarhraun eruption, any effect of rising magma on surface CO2 fluxes is limited to a period of less than two days before eruption.
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The data that support the findings of this study, including Supplementary Datasets 1–3 and Excel spreadsheet versions of Supplementary Tables 1–5, are available from the BGS National Geoscience Data Centre at: https://doi.org/10.5285/0ad0959d-aa0e-4b79-9077-20216a02922a.
We are unable to make the computer code associated with this paper available at this time because it will be the focus of a future methods paper. The diffusion model code and Bayesian inversion in its current format are available on request from the corresponding author.
Cashman, K. V., Sparks, R. S. J. & Blundy, J. D. Vertically extensive and unstable magmatic systems: a unified view of igneous processes. Science 355, eaag3055 (2017).
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).
Costa, F. & Dungan, M. Short time scales of magmatic assimilation from diffusion modeling of multiple elements in olivine. Geology 33, 837–840 (2005).
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).
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).
Rae, A. S. et al. Time scales of magma transport and mixing at Kilauea volcano, Hawai’i. Geology 44, 463–466 (2016).
Hartley, M. E., Morgan, D. J., Maclennan, J., Edmonds, M. & Thordarson, T. Tracking timescales of short-term precursors to large basaltic fissure eruptions through Fe–Mg diffusion in olivine. Earth Planet. Sci. Lett. 439, 58–70 (2016).
Pankhurst, M. J., Morgan, D. J., Thordarson, T. & Loughlin, S. C. Magmatic crystal records in time, space, and process, causatively linked with volcanic unrest. Earth Planet. Sci. Lett. 493, 231–241 (2018).
Peslier, A. H., Woodland, A. B. & Wolff, J. A. Fast kimberlite ascent rates estimated from hydrogen diffusion profiles in xenolithic mantle olivines from southern Africa. Geochim. Cosmochim. Acta 72, 2711–2722 (2008).
Demouchy, S., Jacobsen, S. D., Gaillard, F. & Stern, C. R. Rapid magma ascent recorded by water diffusion profiles in mantle olivine. Geology 34, 429–432 (2006).
Peslier, A. H., Bizimis, M. & Matney, M. Water disequilibrium in olivines from Hawaiian peridotites: recent metasomatism, H diffusion and magma ascent rates. Geochim. Cosmochim. Acta 154, 98–117 (2015).
Ruprecht, P. & Plank, T. Feeding andesitic eruptions with a high-speed connection from the mantle. Nature 500, 68–72 (2013).
Staples, R. K. et al. Färoe-Iceland Ridge Experiment 1. Crustal structure of northeastern Iceland. J. Geophys. Res. 102(B4), 7849–7866 (1997).
Maclennan, J. et al. Melt mixing and crystallization under Theistareykir, northeast Iceland. Geochem. Geophys. Geosyst. 4, 8624 (2003).
Winpenny, B. & Maclennan, J. A partial record of mixing of mantle melts preserved in Icelandic phenocrysts. J. Petrol. 52, 1791–1812 (2011).
Neave, D. A. & Putirka, K. D. A new clinopyroxene-liquid barometer, and implications for magma storage pressures under Icelandic rift zones. Am. Mineral. 102, 777–794 (2017).
Maclennan, J., McKenzie, D., Hilton, F., Gronvöld, K. & Shimizu, N. Geochemical variability in a single flow from northern Iceland. J. Geophys. Res. 108(B1), 2007 (2003).
Bender, J., Hodges, F. & Bence, A. Petrogenesis of basalts from the project FAMOUS area: experimental study from 0 to 15 kbars. Earth Planet. Sci. Lett. 41, 277–302 (1978).
Weaver, J. S. & Langmuir, C. H. Calculation of phase equilibrium in mineral-melt systems. Comput. Geosci. 16, 1–19 (1990).
Hauri, E. H. et al. CO2 content beneath northern Iceland and the variability of mantle carbon. Geology 46, 55–58 (2018).
Thomson, A. & Maclennan, J. The distribution of olivine compositions in Icelandic basalts and picrites. J. Petrol. 54, 745–768 (2012).
Dohmen, R., Faak, K. & Blundy, J. D. Chronometry and speedometry of magmatic processes using chemical diffusion in olivine, plagioclase and pyroxenes. Rev. Mineral. Geochem. 83, 535–575 (2017).
Shea, T., Lynn, K. J. & Garcia, M. O. Cracking the olivine zoning code: distinguishing between crystal growth and diffusion. Geology 43, 935–938 (2015).
Spandler, C. & O’Neill, H. S. C. Diffusion and partition coefficients of minor and trace elements in San Carlos olivine at 1,300 °C with some geochemical implications. Contrib. Mineral. Petrol. 159, 791–818 (2010).
Zhukova, I., O’Neill, H. & Campbell, I. H. A subsidiary fast-diffusing substitution mechanism of Al in forsterite investigated using diffusion experiments under controlled thermodynamic conditions. Contrib. Mineral. Petrol. 172, 53 (2017).
Alnæs, M. et al. The FEniCS project version 1.5. Arch. Numer. Softw. 3, 9–23 (2015).
Feroz, F., Hobson, M. & Bridges, M. MultiNest: an efficient and robust Bayesian inference tool for cosmology and particle physics. Mon. Not. R. Astron. Soc. 398, 1601–1614 (2009).
Sugawara, T. Empirical relationships between temperature, pressure, and MgO content in olivine and pyroxene saturated liquid. J. Geophys. Res. 105(B4), 8457–8472 (2000).
Shorttle, O. et al. Fe-XANES analyses of Reykjanes Ridge basalts: implications for oceanic crust’s role in the solid Earth oxygen cycle. Earth Planet. Sci. Lett. 427, 272–285 (2015).
Chakraborty, S. Rates and mechanisms of Fe–Mg interdiffusion in olivine at 980-1300 °C. J. Geophys. Res. 102(B6), 12317–12331 (1997).
Petry, C., Chakraborty, S. & Palme, H. Experimental determination of Ni diffusion coefficients in olivine and their dependence on temperature, composition, oxygen fugacity, and crystallographic orientation. Geochim. Cosmochim. Acta 68, 4179–4188 (2004).
Dohmen, R., Becker, H.-W. & Chakraborty, S. Fe–Mg diffusion in olivine I: experimental determination between 700 and 1,200 °C as a function of composition, crystal orientation and oxygen fugacity. Phys. Chem. Miner. 34, 389–407 (2007).
Dohmen, R. & Chakraborty, S. Fe–Mg diffusion in olivine II: point defect chemistry, change of diffusion mechanisms and a model for calculation of diffusion coefficients in natural olivine. Phys. Chem. Miner. 34, 409–430 (2007).
Holzapfel, C., Chakraborty, S., Rubie, D. & Frost, D. Effect of pressure on Fe–Mg, Ni and Mn diffusion in (FexMg1−x)2SiO4 olivine. Phys. Earth Planet. Inter. 162, 186–198 (2007).
Zhukova, I., O’Neill, H. S. C., Campbell, I. H. & Kilburn, M. R. The effect of silica activity on the diffusion of Ni and Co in olivine. Contrib. Mineral. Petrol. 168, 1029 (2014).
Jollands, M., Hermann, J., O’Neill, H. S. C., Spandler, C. & Padrón-Navarta, J. Diffusion of Ti and some divalent cations in olivine as a function of temperature, oxygen fugacity, chemical potentials and crystal orientation. J. Petrol. 57, 1983–2010 (2016).
Shea, T., Costa, F., Krimer, D. & Hammer, J. E. Accuracy of timescales retrieved from diffusion modeling in olivine: a 3D perspective. Am. Mineral. 100, 2026–2042 (2015).
Gudmundsson, M. T. et al. Gradual caldera collapse at Bárðarbunga volcano, Iceland, regulated by lateral magma outflow. Science 353, aaf8988 (2016).
Anderson, A. CO2 and the eruptibility of picrite and komatiite. Lithos 34, 19–25 (1995).
White, R. S. et al. Dynamics of dyke intrusion in the mid-crust of Iceland. Earth Planet. Sci. Lett. 304, 300–312 (2011).
Hooper, A. et al. Increased capture of magma in the crust promoted by ice-cap retreat in Iceland. Nat. Geosci. 4, 783–786 (2011).
Tarasewicz, J., Brandsdóttir, B., White, R. S., Hensch, M. & Thorbjarnardóttir, B. Using microearthquakes to track repeated magma intrusions beneath the Eyjafjallajökull stratovolcano, Iceland. J. Geophys. Res. 117, B00C06 (2012).
Hudson, T. et al. Deep crustal melt plumbing of Bárðarbunga volcano, Iceland. Geophys. Res. Lett. 44, 8785–8794 (2017).
Key, J., White, R. S., Soosalu, H. & Jakobsdóttir, S. S. Multiple melt injection along a spreading segment at Askja, Iceland. Geophys. Res. Lett. 38, L05301 (2011).
Aiuppa, A. et al. Unusually large magmatic CO2 gas emissions prior to a basaltic paroxysm. Geophys. Res. Lett. 37, L17303 (2010).
Bali, E., Hartley, M., Halldórsson, S., Gudfinnsson, G. & Jakobsson, S. Melt inclusion constraints on volatile systematics and degassing history of the 2014–2015 Holuhraun eruption, Iceland. Contrib. Mineral. Petrol. 173, 9 (2018).
Schwandner, F. M. et al. Spaceborne detection of localized carbon dioxide sources. Science 358, eaam5782 (2017).
Chiodini, G., Cioni, R., Guidi, M., Raco, B. & Marini, L. Soil CO2 flux measurements in volcanic and geothermal areas. Appl. Geochem. 13, 543–552 (1998).
Shishkina, T., Botcharnikov, R., Holtz, F., Almeev, R. & Portnyagin, M. V. Solubility of H2O-and CO2-bearing fluids in tholeiitic basalts at pressures up to 500 MPa. Chem. Geol. 277, 115–125 (2010).
Vergniolle, S. & Jaupart, C. Separated two-phase flow and basaltic eruptions. J. Geophys. Res. 91(B12), 12842–12860 (1986).
Poland, M. P., Miklius, A., Sutton, A. J. & Thornber, C. R. A mantle-driven surge in magma supply to Kilauea Volcano during 2003–2007. Nat. Geosci. 5, 295–300 (2012).
Bradshaw, R. W. & Kent, A. J. The analytical limits of modeling short diffusion timescales. Chem. Geol. 466, 667–677 (2017).
QUANTAX CrystalAlign (Bruker Nano, 2010).
Bachmann, F., Hielscher, R. & Schaeben, H. in Texture and Anisotropy of Polycrystals III. vol. 160 (eds Klein, H. & Schwarzer, R. A.) 63–68 (Trans Tech, 2010).
MATLAB v.9.10.0 (R2016b edition) (MathWorks Inc., 2016).
Coogan, L., Hain, A., Stahl, S. & Chakraborty, S. Experimental determination of the diffusion coefficient for calcium in olivine between 900 °C and 1500 °C. Geochim. Cosmochim. Acta 69, 3683–3694 (2005).
Ito, M. & Ganguly, J. Diffusion kinetics of Cr in olivine and 53Mn–53Cr thermochronology of early solar system objects. Geochim. Cosmochim. Acta 70, 799–809 (2006).
Oeser, M., Ruprecht, P. & Weyer, S. Combined Fe-Mg chemical and isotopic zoning in olivine constraining magma mixing-to-eruption timescales for the continental arc volcano Irazú (Costa Rica) and Cr diffusion in olivine. Am. Mineral. 103, 582–599 (2018).
Jollands, M. et al. Substitution and diffusion of Cr2+ and Cr3+ in synthetic forsterite and natural olivine at 1200-1500 °C and 1 bar. Geochim. Cosmochim. Acta 220, 407–428 (2018).
Costa, F., Dohmen, R. & Chakraborty, S. Time scales of magmatic processes from modeling the zoning patterns of crystals. Rev. Mineral. Geochem. 69, 545–594 (2008).
Yang, H.-J., Kinzler, R. J. & Grove, T. Experiments and models of anhydrous, basaltic olivine-plagioclase-augite saturated melts from 0.001 to 10 kbar. Contrib. Mineral. Petrol. 124, 1–18 (1996).
Kress, V. C. & Carmichael, I. S. The compressibility of silicate liquids containing Fe2O3 and the effect of composition, temperature, oxygen fugacity and pressure on their redox states. Contrib. Mineral. Petrol. 108, 82–92 (1991).
Ghiorso, M. S. & Sack, R. O. Chemical mass transfer in magmatic processes IV. A revised and internally consistent thermodynamic model for the interpolation and extrapolation of liquid-solid equilibria in magmatic systems at elevated temperatures and pressures. Contrib. Mineral. Petrol. 119, 197–212 (1995).
Gualda, G. A., Ghiorso, M. S., Lemons, R. V. & Carley, T. L. Rhyolite-MELTS: a modified calibration of melts optimized for silica-rich, fluid-bearing magmatic systems. J. Petrol. 53, 875–890 (2012).
Sigurdsson, I. A., Steinthorsson, S. & Grönvold, K. Calcium-rich melt inclusions in Cr-spinels from Borgarhraun, northern Iceland. Earth Planet. Sci. Lett. 183, 15–26 (2000).
Girona, T. & Costa, F. DIPRA: a user-friendly program to model multi-element diffusion in olivine with applications to timescales of magmatic processes. Geochem. Geophys. Geosyst. 14, 422–431 (2013).
Chakraborty, S. Diffusion coefficients in olivine, wadsleyite and ringwoodite. Rev. Mineral. Geochem. 72, 603–639 (2010).
Costa, F. & Morgan, D. in Timescales of Magmatic Processes: From Core to Atmosphere (eds Dosseto, A. et al.) 125–159 (Blackwell, 2010).
Meißner, E. Messung von kurzen Konzentrationsprofilen mit Hilfe der Analytischen Transmissionselektronenmikroskopie (TEM-EDX) am Beispiel der Bestimmung von Diffusionskoeffizienten für die Mg-Fe-Interdiffusion in Olivin. PhD thesis, Univ. Bayreuth (2000).
Feroz, F., Hobson, M., Cameron, E. & Pettitt, A. Importance nested sampling and the MultiNest algorithm. Preprint at https://arxiv.org/abs/1306.2144 (2013).
Buchner, J. et al. X-ray spectral modelling of the AGN obscuring region in the CDFS: Bayesian model selection and catalogue. Astron. Astrophys. 564, A125 (2014).
Crank, J. The Mathematics of Diffusion (Oxford Univ. Press, 1979).
Paquet, F., Dauteuil, O., Hallot, E. & Moreau, F. Tectonics and magma dynamics coupling in a dyke swarm of Iceland. J. Struct. Geol. 29, 1477–1493 (2007).
Lange, R. & Carmichael, I. S. Thermodynamic properties of silicate liquids with emphasis on density, thermal expansion and compressibility. Rev. Mineral. Geochem. 24, 25–64 (1990).
Giordano, D., Russell, J. K. & Dingwell, D. B. Viscosity of magmatic liquids: a model. Earth Planet. Sci. Lett. 271, 123–134 (2008).
Thordarson, T. & Self, S. The Laki (Skaftár Fires) and Grmsvötn eruptions in 1783–1785. Bull. Volcanol. 55, 233–263 (1993).
This research was funded by a NERC studentship awarded to E.J.F.M (NE/L002507/1). We are grateful to I. Buisman and G. Lampronti for assistance with the EPMA and EBSD analyses, respectively. We would also like to thank C. Richardson for helpful advice on FEniCS.
The authors declare no competing interests.
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Supplementary Figs. 1–46 and Supplementary Tables 1–5.
Olivine EPMA data and model initial conditions.
Olivine diffusion experimental dataset used in this study.
Supplementary inversion results dataset.
Olivine diffusion equation regression parameters.
Covariance matrices for olivine diffusion equations.
Covariance matrices for aSiO2-dependent olivine diffusion equations.
Angles between the EPMA profile and the main crystallographic axes.
Median timescales and 1σ errors.
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Mutch, E.J.F., Maclennan, J., Shorttle, O. et al. Rapid transcrustal magma movement under Iceland. Nat. Geosci. 12, 569–574 (2019). https://doi.org/10.1038/s41561-019-0376-9
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