Skip to main content Accessibility help
  • Print publication year: 2020
  • Online publication date: April 2020

6 - Formation and Dynamics of Magma Chambers and Reservoirs


A magma chamber is the heart of every polygenetic volcano. Many, presumably most, polygenetic volcanoes have two magma chambers: one shallow crustal chamber and another deep-seated chamber, which we here refer to as a reservoir. Together, the reservoir and the shallow chamber constitute a double magma chamber. The complex interaction between the source reservoir and the chamber determines the frequency of injection of inclined sheets and dikes. Together with the mechanical layering and local stresses in the crustal segment, the double chamber also largely controls the frequency and sizes of eruptions in the volcano to which it supplies magma. We have learned that most shallow chambers evolve from sills and are located in the upper crust. The deep-seated reservoirs, by contrast, are normally located in the lower crust or upper mantle. If located in the crust, they may also evolve from sills; if located in the upper mantle, they may evolve as magma accumulations in regions of low potential energy. The accurate determination of the location of active magma chambers is generally difficult.

Alfaro, R., Brandsdottir, B., Rowlands, D. P., et al., 2007. Structure of the Grimsvötn central volcano under the Vatnajökull icecap. Geophysical Journal International, 168, 863876.
Andrew, R. E. B., Gudmundsson, A., 2007. Distribution, structure, and formation of Holocene lava shields in Iceland. Journal of Volcanology and Geothermal Research, 168, 137154.
Auger, E., Gasparini, P., Virieax, J., Zollo, A., 2001. Seismic evidence of an extended magmatic sill under Mt. Vesuvius. Science, 294, 15101512.
Baran, J. M., Cochran, J. R., Carbotte, S. M., Nedimovic, M. R., 2005. Variations in upper crustal structure due to variable mantle temperature along the Southeast Indian Ridge. Geochemistry, Geophysics, Geosystems, 6, doi:10.1029/2005GC000943.
Beachly, M. W., Hooft, E. E. E., Toomey, D. R., Waite, G. P., 2012. Upper crustal structure of Newberry Volcano from P-wave tomography and finite difference waveform modeling. Journal of Geophysical Research, 117, doi:10.1029/2012JB009458.
Bear, J., 1972. Dynamics of Fluids in Porous Media. Amsterdam: Elsevier.
Becerril, L., Galindo, I., Gudmundsson, A., Morales, J. M., 2013. Depth of origin of magma in eruptions. Scientific Reports, 3, 2762, doi:10.1038/srep02762.
Bjarnason, I. Th., 2008. An Iceland hotspot saga. Jokull, 58, 316.
Björnsson, A., 1985. Dynamics of crustal rifting in NE Iceland. Journal of Geophysical Research, 90, 1015110162.
Blake, D. H., 1966. The net-veined complex of the Austurhorn intrusion, southeastern Iceland. Journal of Geology, 74, 891907.
Brandsdottir, B., Menke, W. H., 2008. The seismic structure of Iceland. Jokull, 58, 1734.
Browning, J., Gudmundsson, A., 2015a. Surface displacements resulting from magma-chamber roof subsidence, with application to the 2014–2015 Bardarbunga–Holuhraun volcanotectonic episode in Iceland. Journal of Volcanology and Geothermal Research, 308, 8298.
Browning, J., Gudmundsson, A., 2015b. Caldera faults capture and deflect inclined sheets: An alternative mechanism of ring-dike formation. Bulletin of Volcanology, 77, 889, doi:10.1007/s00445-014-0889-4.
Browning, J., Drymoni, K., Gudmundsson, A., 2015. Forecasting magma-chamber rupture at Santorini volcano, Greece. Scientific Reports, 5, doi:10.1038/srep15785.
Canales, J. P., Nedimovic, M. R., Kent, G. M., Carbotte, S. M., Detrick, R. S., 2009. Seismic reflection images of a near-axis melt sill within the lower crust at the Juan de Fuca ridge. Nature, 460, 8993.
Carbotte, S. M, Detrick, R. S., Harding, A., et al., 2006. Rift topography linked to magmatism at the intermediate spreading Juan de Fuca Ridge. Geology, 34, 209212.
Cavalcante, G. C. G., Vauchez, A., Merlet, C., et al., 2014. Thermal conditions during deformation of partially molten crust from Titani geothermometry: rheological implications for the anatectic domain of the Araçuaí belt, Eastern Brazil. Solid Earth Discussions, 6, 12991333.
Chaussard, E., Amelung, F., 2014. Regional controls on magma ascent and storage in volcanic arcs. Geochemistry, Geophysics, Geosystems, 15, doi:10.1002/2013GC005216.
Chen, Y., 2004. Modelling the thermal structure of the oceanic crust. In German, C., Lin, J., Parson, L. M. (eds.), Mid-Ocean Ridges: Hydrothermal Interactions between the Lithosphere and Oceans. Geophysical Monograph 148. Washington, DC.: American Geophysical Union.
Crawford, W. C., Webb, S. C., 2002. Variations in the distribution of magma in the lower crust and at the Moho beneath the East Pacific Rise at 9 degrees–10 degrees N. Earth and Planetary Science Letters, 203, 117130.
de Zeeuw-van Dalfsen, E., Pedersen, R., Sigmundsson, F., Pagli, C., 2004. Satellite radar interferometry 1993–1999 suggests deep accumulation of magma near the crust-mantle boundary at the Krafla volcanic system, Iceland. Geophysical Research Letters, 31, doi:10.1029/2004GL020059.
de Zeeuw-van Dalfsen, E., Pedersen, R., Hooper, A., Sigmundsson, F., 2012. Subsidence of Askja caldera 2000–2009: Modelling of deformation processes at an extensional plate boundary, constrained by time series InSAR analysis. Journal of Volcanology and Geothermal Research, 213–214, 7282.
Detrick, R. S., Sinton, J. M., Ito, G., et al., 2002. Correlated geophysical, geochemical, and volcanological manifestation of plume-ridge interaction along the Galapagos Spreading Center. Geochemistry, Geophysics, Geosystems, 3, doi:1029/2002gc000350.
Dobran, F., 2001. Volcanic Processes. Mechanisms in Material Transport. New York, NY: Kluwer.
Fagents, S. A., Gregg, T. K. P., Lopes, R. M. C. (eds.), 2013. Modeling Volcanic Processes: The Physics and Mathematics of Volcanism. Cambridge: Cambridge University Press.
Fleisch, D., 2012. A Students Guide to Vectors and Tensors. Cambridge: Cambridge University Press.
Furman, T., Meyer, P. S., Frey, F., 1992. Evolution of Icelandic central volcanoes: evidence from the Austurhorn intrusion, southeastern Iceland. Bulletin of Volcanology, 55, 4562.
Galindo, I., Gudmundsson, A., 2012. Basaltic feeder dykes in rift zones: geometry, emplacement, and effusion rates. Natural Hazards and Earth System Sciences, 12, 36833700.
Gonnermann, H. M., Manga, M., 2013. Dynamics of magma ascent in the volcanic conduit. In Fagents, S. A., Gregg, T. K. P., Lopes, R. M. C. (eds.), Modeling Volcanic Processes. Cambridge University Press, Cambridge, pp. 5584.
Greenland, L. P., Rose, W. I., Stokes, J. B., 1985. An estimate of gas emissions and magmatic gas content from Kilauea volcano. Geochimica et Cosmochimica Acta, 49, 125129.
Greenland, L. P., Okamura, A. T., Stokes, J. B., 1988. Constraints on the mechanics of the eruption. In Wolfe, E. W (ed.), The Puu Oo Eruption of Kilauea Volcano, Hawaii: Episodes Through 20, January 3, 1983 Through June 8, 1984. US Geological Survey Professional Paper, 1463. Denver, CO: US Geological Survey, pp. 155164.
Griffith, D. J., 2014. Introduction to Electrodynamics. Cambridge: Pearson.
Gudmundsson, A., 1987. Formation and mechanics of magma reservoirs in Iceland. Geophysical Journal of the Royal Astronomical Society, 91, 2741.
Gudmundsson, A., 1990. Emplacement of dikes, sills and crustal magma chambers at divergent plate boundaries. Tectonophysics, 176, 257275.
Gudmundsson, A., 1995. The geometry and growth of dykes. In Baer, G., Heimann, A. (eds.), Physics and Chemistry of Dykes. Rotterdam: Balkema, pp. 2334.
Gudmundsson, A., 2006. How local stresses control magma-chamber ruptures, dyke injections, and eruptions in composite volcanoes. Earth-Science Reviews, 79, 131.
Gudmundsson, A., 2007. Conceptual and numerical models of ring-fault formation. Journal of Volcanology and Geothermal Research, 164, 142160.
Gudmundsson, A., 2011. Rock Fractures in Geological Processes. Cambridge: Cambridge University Press.
Gudmundsson, A., 2012. Magma chambers: formation, local stresses, excess pressures, and compartments. Journal of Volcanology and Geothermal Research, 237–238, 1941.
Gudmundsson, A., 2016. The mechanics of large volcanic eruptions. Earth-Science Reviews, 163, 7293.
Gudmundsson, A., 2017. The Glorious Geology of Iceland’s Golden Circle. Berlin: Springer Verlag.
Gudmundsson, A., Brenner, S. L., 2004. How mechanical layering affects local stresses, unrests, and eruptions of volcanoes. Geophysical Research Letters, 31,
Gudmundsson, A., Oskarsson, N., Gronvold, K., et al., 1992. The 1991 eruption of Hekla, Iceland.Bulletin of Volcanology, 54, 238246.
Gudmundsson, A., Lecoeur, N., Mohajeri, N., Thordarson, T., 2014. Dike emplacement at Bardarbunga, Iceland, induces unusual stress changes, caldera deformation, and earthquakes. Bulletin of Volcanology, 76, 869, doi:10.1007/s00445-014-0869-8.
Guo, X., 2013. Density and Compressibility of FeO-Bearing Silicate Melt: Relevance to Magma Behavior in the Earth. PhD Thesis, University of Michigan, Ann Arbor, MI.
Harris, A. J. L., Murray, J. B., Aries, S. E., et al., 2000. Effusion rate trends at Etna and Krafla and their implications for eruptive mechanisms. Journal of Volcanology and Geothermal Research, 102, 237270.
Hollingsworth, J., Leprince, S., Ayoub, F., Avouac, J. P., 2012. Deformation during the 1975–1984 Krafla rifting crisis, NE Iceland, measured from historical optical imagery. Journal of Geophysical Research, 117, doi:10.1029/2012JB009140.
Hreinsdottir, S., Sigmundsson, F., Roberts, M. J., et al., 2014. Volcanic plume height correlated with magma-pressure change at Grimsvötn Volcano, Iceland. Nature Geoscience, 7, 214218,
Kent, G. M., Harding, A. J., Orcutt, J. A. 1990. Evidence for a smaller magma chamber beneath the East Pacific Rise at 9°30’ N. Nature 344, 650653.
Koulakov, I., Gordeev, E. I., Dobretsov, N. L., et al., 2011. Feeding volcanoes of the Kluchevskoy group from the results of local earthquake tomography. Geophysical Research Letters, 38, L09305, doi:10.1029/2011GL046957.
Kress, V. C., Carmichael, I. S. E., 1991. The compressibility of silicate liquids containing Fe2O3 and the effect of composition, temperature, oxygen fugacity and pressure on their redox states. Contributions to Mineralogy and Petrology, 108, 8292.
Lauthold, J., Muntener, O., Baumgartener, L. P., et al., 2014. A detailed geochemical study of a shallow arc-related laccolith; the Torres del Paine Mafic Complex (Patagonia). Journal of Petrology, 54, 273303.
Lin, G., Amelung, F. Y., Lavallée, Y., Okubo, P. G., 2014 . Seismic evidence for a crustal magma reservoir beneath the upper east rift zone of Kilauea volcano, Hawaii. Geology, 42, 187190.
Macdonald, K. C., 1982. Mid-ocean ridges: fine scale tectonic, volcanic and hydrothermal processes within a plate boundary. Annual Review of Earth and Planetary Sciences, 10, 155190.
Malfait, W. J., Sanchez-Valle, C., Ardia, P., Médard, E., Lerch, P., 2011. Compositional dependent compressibility of dissolved water in silicate glasses. American Mineralogist, 96, 14021409.
Michel, J., Baumgartner, L., Putlitz, B., Schaltegger, U., Ovtcharova, M., 2008. Incremental growth of the Patagonian Torres del Paine laccolith over 90 k.y. Geology, 36, 459462, doi:10.1130/G24546A.1.
Murase, T., McBirney, A. R., 1973. Properties of some common igneous rocks and their melts at high temperatures. Geological Society of America Bulletin, 84, 35633592.
Oladottir, B., Sigmarsson, O., Larsen, G., Thordarson, T., 2008. Katla volcano, Iceland: magma composition, dynamics and eruption frequency as recorded by Holocene tephra layers. Bulletin of Volcanology, 70, 475493.
Opheim, J. A., Gudmundsson, A., 1989. Formation and geometry of fractures, and related volcanism, of the Krafla Fissure Swarm, Northeast Iceland. Geological Society of America Bulletin, 101, 16081622.
Orcutt, J. A. 1987. Structure of the earth: oceanic crust and uppermost mantle. Reviews of Geophysics, 25, 11771196.
Pagli, C., Wright, T. J., Ebinger, C. J., et al., 2012. Shallow axial chamber at the slow-spreading Erta Ale Ridge. Nature Geoscience, doi:10.1038/NGEO1414.
Paulatto, M., Annen, C., Henstock, T. J., et al., 2012. Magma chamber properties from integrated seismic tomography and thermal modeling at Montserrat. Geochemistry, Geophysics, Geosystems, 13, Q01014, doi:10.1029/2011GC003892.
Poland, M. P., Takahashi, T. J., Landowski, C. M. (eds.), 2014a. Characteristics of Hawaiian Volcanoes. US Geological Survey Professional Paper, 1801. Denver, CO: US Geological Survey.
Poland, M. P., Miklius, A., Montgomery-Brown, E. K., 2014b. Magma supply, storage, and transport at shield-stage Hawaiian volcanoes. In Poland, M. P., Takahashi, T. J., Landowski, C. M. (eds.), Characteristics of Hawaiian Volcanoes. US Geological Survey Professional Paper, 1801. Denver, CO: US Geological Survey, pp. 179234.
Reverso, T., Vandemeulebrouck, J., Jouanne, F., et al., 2014. A two-magma chamber model as a source of deformation at Grimsvötn Volcano, Iceland. Journal of Geophysical Research, 119, 46664683.
Ritchie, D., Gates, A. E., 2001. Encyclopedia of Earthquakes and Volcanoes. New York, NY: Facts on File.
Roobol, M. J., 1974. Geology of the Vesturhorn intrusion, SE Iceland. Geological Magazine, 111, 273285.
Rossi, M. J., 1996. Morphology and mechanism of eruption of postglacial lava shields in Iceland. Bulletin of Volcanology, 57, 530540.
Saemundsson, K., Sigmundsson, F., 2013. The North Volcanic Zone, Krafla. In Solnes, J., Sigmundsson, F., Bessason, B. (eds.), Natural Hazards in Iceland: Volcanic Eruptions and Earthquakes. Reykjavik: Vidlagatrygging/Haskolautgafan, pp. 324337 (in Icelandic).
Searle, R., 2013. Mid-Ocean Ridges. Cambridge: Cambridge University Press.
Seifert, R., 2013 Compressibility of Volatile-Bearing Magmatic Liquids. PhD Thesis, ETH, Zurich.
Sheth, H., 2018. A Photographic Atlas of Flood Basalt Volcanism. Berlin: Springer.
Singh, S. C., Crawford, W. C., Carton, H., et al., 2006. Discovery of a magma chamber and faults beneath a Mid-Atlantic Ridge hydrothermal field. Nature, 442, 10291032.
Sinha, M. C., Constable, S. C., Peirce, C., et al., 1998. Magmatic processes at slow-spreading ridges: implications of the RMESSES experiment at 57°45’ N on the Mid-Atlantic Ridge. Geophysical Journal International, 135, 731745.
Soosalu, H., Key, J., White, R.S., et al. 2010. Lower-crustal earthquakes caused by magma movement beneath Askja volcano on the north Iceland rift. Bulletin of Volcanology, 72, 5562.
Sturkell, E., Einarsson, P., Sigmundsson, F., et al., 2006. Volcano geodesy and magma dynamics in Iceland. Journal of Volcanology and Geothermal Research, 150, 1434.
Sturkell, E., Sigmundsson, F., Geirsson, H., et al., 2008. Multiple volcano deformation sources in a post-rifting period: 1989–2005 behaviour of Krafla, Iceland constrained by levelling, tilt and GPS observations. Journal of Volcanology and Geothermal Research, 177, 405417.
Sturkell, E., Einarsson, P., Sigmundsson, F. et al., 2010. Katla and Eyjafjallajökull volcanoes. Developments in Quaternary Sciences, 13, 521.
Tenzer, R., Gladkikh, V., 2014. Assessment of density variations of marine sediments with ocean and sediment depths. The Scientific World Journal, 2, doi:10.1155/2014/823296
Thorarinsson, S. B., Tegner, C., 2009. Magma chamber processes in central volcanic systems of Iceland: constraints from layered gabbro of the Austurhorn intrusive complex. Contributions to Mineralogy and Petrology, 158, 223244.
Thordarson, T., Hoskuldsson, A., 2008. Postglacial volcanism in Iceland. Jokull, 58, 197228.
Thordarson, T., Larsen, G., 2007. Volcanism in Iceland in historical time: volcano types, eruption styles and eruptive history. Journal of Geodynamics, 43, 118152.
Tryggvason, E. 1984. Widening of the Krafla Fissure Swarm during the 1975–1981 volcano-tectonic episode. Bulletin of Volcanology, 47, 4769.
Tryggvason, E. 1986. Multiple magma reservoirs in a rift zone volcano: ground deformation and magma transport during the September 1984 eruption of Krafla, Iceland. Journal of Volcanology and Geothermal Research, 28, 144.
Walker, G. P. L., 1965. Some aspects of Quaternary volcanism in Iceland. Quaternary Journal of the Geological Society, 49, 2540.
Wang, H. F., 2000. Theory of Linear Poroelasticity. Princeton, NJ: Princeton University Press.
Williams, H., McBirney, A. R., 1979. Volcanology. San Francisco, CA: Freeman.
Woods, A. W., Huppert, H. E., 2003. On magma chamber evolution during slow effusive eruptions. Journal of Geophysical Research, 108, 2403, doi:10.1029/2002JB002019.
Zollo, A., Maercklin, N., Vassallo, M., et al., 2008. Seismic reflections reveal a massive melt layer feeding Campi Flegrei caldera. Geophysical Research Letters, 35, L12306, doi:10.1029/2008GL034242.