Articles | Volume 37, issue 4
https://doi.org/10.5194/ejm-37-385-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/ejm-37-385-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
04 Jul 2025
Research article |
| 04 Jul 2025
| 04 Jul 2025
Vesiculation dynamics – Part 1: Decompression-induced H2O vesicle formation in the Lower Laacher See phonolitic melt
Patricia Louisa Marks
CORRESPONDING AUTHOR
Department of Geosciences, Eberhard Karls University of Tübingen, Tübingen 72074, Germany
Marcus Nowak
Department of Geosciences, Eberhard Karls University of Tübingen, Tübingen 72074, Germany
Related authors
Patricia Louisa Marks and Marcus Nowak
Eur. J. Mineral., 37, 413–435, https://doi.org/10.5194/ejm-37-413-2025, https://doi.org/10.5194/ejm-37-413-2025, 2025
Short summary
Short summary
As magma ascends, H2O-supersaturated melt forms fluid vesicles, creating high vesicle number densities (VNDs) and increasing melt porosity, accelerating magma ascent. This study examines how VNDs vary with decompression rate as vesicles begin to coalesce. The shift from decompression-rate-independent to decompression-rate-dependent VND can strongly influence eruption styles, creating permeable channels or forming closed-porosity foams that trap pressurized gas, potentially leading to explosive eruptions.
Patricia Louisa Marks, Anja Allabar, and Marcus Nowak
Eur. J. Mineral., 35, 613–633, https://doi.org/10.5194/ejm-35-613-2023, https://doi.org/10.5194/ejm-35-613-2023, 2023
Short summary
Short summary
These results represent the first high-pressure and high-temperature degassing experiments simulating the injection of basaltic melt into a hydrous rhyolitic melt reservoir. Diffusion processes in the contact zone of the melts lead to a depletion of alkalis in the rhyolitic melt interface. The reduced alkali concentration significantly decreases the H2O solubility of the rhyolitic melt and promotes enhanced H2O vesicle formation and further degassing, which can trigger volcanic eruptions.
Patricia Louisa Marks and Marcus Nowak
Eur. J. Mineral., 37, 413–435, https://doi.org/10.5194/ejm-37-413-2025, https://doi.org/10.5194/ejm-37-413-2025, 2025
Short summary
Short summary
As magma ascends, H2O-supersaturated melt forms fluid vesicles, creating high vesicle number densities (VNDs) and increasing melt porosity, accelerating magma ascent. This study examines how VNDs vary with decompression rate as vesicles begin to coalesce. The shift from decompression-rate-independent to decompression-rate-dependent VND can strongly influence eruption styles, creating permeable channels or forming closed-porosity foams that trap pressurized gas, potentially leading to explosive eruptions.
Patricia Louisa Marks, Anja Allabar, and Marcus Nowak
Eur. J. Mineral., 35, 613–633, https://doi.org/10.5194/ejm-35-613-2023, https://doi.org/10.5194/ejm-35-613-2023, 2023
Short summary
Short summary
These results represent the first high-pressure and high-temperature degassing experiments simulating the injection of basaltic melt into a hydrous rhyolitic melt reservoir. Diffusion processes in the contact zone of the melts lead to a depletion of alkalis in the rhyolitic melt interface. The reduced alkali concentration significantly decreases the H2O solubility of the rhyolitic melt and promotes enhanced H2O vesicle formation and further degassing, which can trigger volcanic eruptions.
Cited articles
Ablay, G. J., Ernst, G. G. J., Marti, J., and Sparks, R. S. J.: The ∼ 2 ka subplinian eruption of Montaña Blanca, Tenerife, Bull. Volcanol., 57, 337–355, https://doi.org/10.1007/BF00301292, 1995.
Airy, G. B.: On the Diffraction of an Object-glass with Circular Aperture, Transactions of the Cambridge Philosophical Society, 5, 283–291, 1834.
Allabar, A. and Nowak, M.: Message in a bottle: Spontaneous phase separation of hydrous Vesuvius melt even at low decompression rates, Earth Planet. Sc. Lett., 501, 192–201, https://doi.org/10.1016/j.epsl.2018.08.047, 2018.
Allabar, A. and Nowak, M.: High spatial resolution analysis of H2O in silicate glass using attenuated total reflection FTIR spectroscopy coupled with a focal plane array detector, Chem. Geol., 556, 119833, https://doi.org/10.1016/j.chemgeo.2020.119833, 2020.
Allabar, A., Dobson, K. J., Bauer, C. C., and Nowak, M.: Vesicle shrinkage in hydrous phonolitic melt during cooling, Contrib. Mineral. Petr., 175, 21, https://doi.org/10.1007/s00410-020-1658-3, 2020a.
Allabar, A., Salis Gross, E., and Nowak, M.: The effect of initial H2O concentration on decompression-induced phase separation and degassing of hydrous phonolitic melt, Contrib. Miner. Petrol., 175, 22, https://doi.org/10.1007/s00410-020-1659-2, 2020b.
Allabar, A., Petri, P. L., Eul, D., and Nowak, M.: An empirical H2O solubility model for peralkaline rhyolitic melts, Contrib. Mineral. Petr., 177, 52, https://doi.org/10.1007/s00410-022-01915-8, 2022.
Balzer, R., Behrens, H., Waurischk, T., Reinsch, S., Müller, R., Kiefer, P., Deubener, J., and Fechtelkord, M.: Water in alkali aluminosilicate glasses, Front. Mater., 7, 85, https://doi.org/10.3389/fmats.2020.00085, 2020.
Behrens, H., Romano, C., Nowak, M., Holtz, F., and Dingwell, D. B.: Near-infrared spectroscopic determination of water species in glasses of the system MAlSi3O8 (M = Li, Na, K): an interlaboratory study, Chem. Geol., 128, 41–63, https://doi.org/10.1016/0009-2541(95)00162-X, 1996.
Berndt, J., Liebske, C., Holtz, F., Freise, M., Nowak, M., Ziegenbein, D., Hurkuck, W., and Koepke, J.: A combined rapid-quench and H2-membrane setup for internally heated pressure vessels: Description and application for water solubility in basaltic melts, Am. Mineral., 87, 1717–1726, https://doi.org/10.2138/am-2002-11-1222, 2002.
Blaine, F., Linnen, R., Holtz, F., and Bruegmann, G.: The effect of Cl on Pt solubility in haplobasaltic melt: implications for micronugget formation and evidence for fluid transport of PGEs, Geochim. Cosmochim. Ac., 75, 7792–7805, https://doi.org/10.1016/j.gca.2011.10.010, 2011.
Bondar, D., Zandonà, A., Withers, A.C., Fei, H., Di Genova, D., Miyajima, N., and Katsura, T.: Rapid-quenching of high-pressure depolymerized hydrous silicate (peridotitic) glasses, J. Non-Crystalline Sol., 578, 121347, https://doi.org/10.1016/j.jnoncrysol.2021.121347, 2022.
Brennen, C. E.: Cavitation and Bubble Dynamics, Oxford University Press, Inc., ISBN 0-19-509409-3, 1995.
Bureau, H. and Keppler, H.: Complete miscibility between silicate melts and hydrous fluids in the upper mantle: experimental evidence and geochemical implications, Earth Planet. Sc. Lett., 165, 187–196, https://doi.org/10.1016/S0012-821X(98)00266-0, 1999.
Burnham, C. W. and Davis, N. F.: The role of H2O in silicate melts, 1: P−V −T relations in the system NaAlSi3O8–H2O to 10 kilobars and 1000 °C, Am. J. Sci., 270, 54–79, https://doi.org/10.2475/ajs.270.1.54, 1971.
Cahn, J. W.: Phase separation by spinodal decomposition in isotropic systems, J. Chem. Phys., 42, 93–99, https://doi.org/10.1063/1.1695731, 1965.
Carroll, M. R. and Blank, J. G.: The solubility of H2O in phonolitic melts, Am. Min., 82, 549–556, https://doi.org/10.2138/am-1997-5-615, 1997.
Cichy, S. B., Botcharnikov, R. E., Holtz, F., and Behrens, H.: Vesiculation and microlite crystallization induced by decompression: a case study of the 1991–1995 Mt Unzen Eruption (Japan), J. Petrol., 52, 1469–1492, https://doi.org/10.1093/petrology/egq072, 2011.
Debenedetti, P. G.: Phase separation by nucleation and by spinodal decomposition: fundamentals, in: Supercritical Fluids, edited by: Kiran, E., Debenedetti, P. G., and Peters, C. J., Nato Science Series E, 366, 123–166, https://doi.org/10.1007/978-94-011-3929-8_5, 2000.
Dubosq, R., Schneider, D. A., Zhou, X., Gault, B., Langelier, B., and Please, P.: Bubbles and atom clusters in rock melts: A chicken and egg problem, J. Volcanol. Geoth. Res., 428, 107574, https://doi.org/10.1016/j.jvolgeores.2022.107574, 2022.
Di Genova, D., Kolzenburg, S., Wiesmaier, S., Dallanave, E., Neuville, D. R., Hess, K. U., and Dingwell, D. B.: A compositional tipping point governing the mobilization and eruption style of rhyolitic magma, Nature, 552, 235–238, https://doi.org/10.1038/nature24488, 2017a.
Di Genova, D., Sicola, S., Romano, C., Vona, A., Fanara, S., and Spina, L.: Effect of iron and nanolites on Raman spectra of volcanic glasses: A reassessment of existing strategies to estimate the water content, Chem. Geol., 475, 76–86, https://doi.org/10.1016/j.chemgeo.2017.10.035, 2017b.
Di Genova, D., Caracciolo, A., and Kolzenburg, S.: Measuring the degree of “nanotilization” of volcanic glasses: Understanding syn-eruptive processes recorded in melt inclusions, Lithos, 318–319, 209–218, https://doi.org/10.1016/j.lithos.2018.08.011, 2018.
Di Genova, D., Brooker, R. A., Mader, H. M., Drewitt, J. W. E., Longo, A., Deubener, J., Neuville, D. R., Fanara, S., Shebanova, O., Anzellini, S., Arzilli, F., Bamber, E. C., Hennet, L., La Spina, G., and Miyajima, N.: In situ observation of nanolite growth in volcanic melt: A driving force for explosive eruptions, Sci. Adv., 6, eabb0413, https://doi.org/10.1126/sciadv.abb0413, 2020.
Di Matteo, V., Carroll, M. R., Behrens, H., Vetere, F., and Brooker, R. A.: Water solubility in trachytic melts, Chem. Geol., 213, 187–196, https://doi.org/10.1016/j.chemgeo.2004.08.042, 2004.
Duan, Z. H. and Zhang, Z. G.: Equation of state of the H2O, CO2, and H2O-CO2 systems up to 10 GPa and 2573.15 K: molecular dynamics simulations with ab initio potential surface, Geochim. Cosmochim. Ac., 70, 2311–2324, https://doi.org/10.1016/j.gca.2006.02.009, 2006.
Ertel, W., O'Neill, H. S. C., Sylvester, P. J., Dingwell, D. B., and Spettel, B.: The solubility of rhenium in silicate melts: implications for the geochemical properties of rhenium at high temperatures, Geochim. Cosmochim. Ac., 65, 2161–2170, https://doi.org/10.1016/S0016-7037(01)00582-8, 2001.
Fanara, S., Behrens, H., and Zhang, Y.: Water diffusion in potassium-rich phonolitic and trachytic melts, Chem. Geol., 346, 149–161, https://doi.org/10.1016/j.chemgeo.2012.09.030, 2013.
Fiege, A., Holtz, F., and Cichy, S. B.: Bubble formation during decompression of andesitic melts, Am. Mineral., 99, 1052–1062, https://doi.org/10.2138/am.2014.4719, 2014.
Gardner, J. E.: Heterogeneous bubble nucleation in highly viscous silicate melts during instantaneous decompression from high pressure, Chem. Geol., 236, 1–12, https://doi.org/10.1016/j.chemgeo.2006.08.006, 2007.
Gardner, J. E.: Surface tension and bubble nucleation in phonolite magmas, Geochim. Cosmochim. Ac., 76, 93–102, https://doi.org/10.1016/j.gca.2011.10.017, 2012.
Gardner, J. E. and Denis, M.-H.: Heterogeneous bubble nucleation on Fe-Ti oxide crystals in highsilica rhyolitic melts, Geochim. Cosmochim. Ac., 68, 3587–3597, https://doi.org/10.1016/j.gca.2004.02.021, 2004.
Gardner, J. E. and Ketcham, R. A.: Bubble nucleation in rhyolite and dacite melts: temperature dependence of surface tension, Contrib. Miner. Petrol., 162, 929–43, https://doi.org/10.1007/s00410-011-0632-5, 2011.
Gardner, J. E., Hilton, M., and Carroll, M. R.: Experimental constraints on degassing of magma: isothermal bubble growth during continuous decompression from high pressure, Earth Planet. Sc. Lett., 168, 201–218, https://doi.org/10.1016/S0012-821X(99)00051-5, 1999.
Gardner, J. E., Ketcham, R. A., and Moore, G.: Surface tension of hydrous silicate melts: constraints on the impact of melt composition, J. Volcanol. Geoth. Res., 267, 68–74, https://doi.org/10.1016/j.jvolgeores.2013.09.007, 2013.
Gardner, J. E., Wadsworth, F. B., Carley, T. L., Llewellin, E. W., Kusumaatmaja, H., and Sahagian, D.: Bubble Formation in Magma, Annu. Rev. Earth Planet. Sci., 51, 131–154. https://doi.org/10.1146/annurev-earth-031621-080308, 2023.
Giordano, D., Potuzak, M., Romano, C., Dingwell, D. B., and Nowak, M.: Viscosity and glass transition temperature of hydrous melts in the system CaAl2Si2O8-CaMgSi2O6, Chem. Geol., 256, 203–215, https://doi.org/10.1016/j.chemgeo.2008.06.027, 2008.
Gondé, C., Martel, C., Pichavant, M., and Bureau, H.: In situ bubble vesiculation in silicic magmas, Am. Mineral., 96, 111–124, https://doi.org/10.2138/am.2011.3546, 2011.
Gonnermann, H. M. and Gardner, J. E.: Homogeneous bubble nucleation in rhyolitic melt: experiments and non-classical theory, Geochem. Geophys. Geosyst., 14, 4758–4773, https://doi.org/10.1002/ggge.20281, 2013.
Hajimirza, S., Gonnermann, H. M., Gardner, J. E., and Giachetti, T.: Predicting homogeneous bubble nucleation in rhyolite, J. Geophys. Res.-Sol. Ea., 124, 2395–2416, https://doi.org/10.1029/2018JB015891, 2019.
Hajimirza, S., Gardner, J. E., and Gonnermann, H. M.: Experimental demonstration of continuous bubble nucleation in rhyolite, J. Volcanol. Geoth. Res., 421, 107417, https://doi.org/10.1016/j.jvolgeores.2021.107417, 2021.
Hamada, M., Laporte, D., Cluzel, N., Koga, K. T., and Kawamoto, T.: Simulating bubble number density of rhyolitic pumices from Plinian eruptions: constraints from fast decompression experiments, Bull. Volcanol., 72, 735–746, https://doi.org/10.1007/s00445-010-0353-z, 2010.
Harms, E. and Schmincke, H. U.: Volatile composition of the phonolitic Laacher See magma (12,900 yr BP): implications for syn-eruptive degassing of S, F, Cl and H2O, Contrib. Miner. Petrol., 138, 84–98, https://doi.org/10.1007/PL00007665, 2000.
Harms, E., Gardner, J. E., and Schmincke, H. U.: Phase equilibria of the Lower Laacher See Tephra (East Eifel, Germany): constraints on pre-eruptive storage conditions of a phonolitic magma reservoir, J. Volcanol. Geoth. Res., 134, 135–148, https://doi.org/10.1016/j.jvolgeores.2004.01.009, 2004.
Hertz, P.: Über den gegenseitigen durchschnittlichen Abstand von Punkten, die mit bekannter mittlerer Dichte im Raume angeordnet sind, Math. Ann., 67, 387–398, https://doi.org/10.1007/BF01450410, 1908.
Higgins, M. D.: Measurement of crystal size distributions, Am. Mineral., 85, 1105–1116, https://doi.org/10.2138/am-2000-8-901, 2000.
Holasek, R. E., Self, S., and Woods, A. W.: Satellite observations and interpretation of the 1991 Mount Pinatubo eruption plumes, J. Geophys. Res., 101, 27635–27655, https://doi.org/10.1029/96JB01179, 1996.
Holtz, F., Dingwell, D. B., and Behrens, H.: Effects of F, B2O3 and P2O5 on the solubility of water in haplogranite melts compared to natural silicate melts, Contrib. Miner. Petrol., 113, 492–501, https://doi.org/10.1007/BF00698318, 1993.
Holtz, F., Behrens, H., Dingwell, D. B., and Johannes, W.: H2O solubility in haplogranitic melts: Compositional, pressure, and temperature dependence, Am. Mineral., 80, 94–108, https://doi.org/10.2138/am-1995-1-210, 1995.
Hurwitz, S. and Navon, O.: Bubble nucleation in rhyolitic melts: experiments at high pressure, temperature, and water content, Earth Planet. Sc. Lett., 122, 267–80, https://doi.org/10.1016/0012-821X(94)90001-9, 1994.
Iacono-Marziano, G., Schmidt, B. C., and Dolfi, D.: Equilibrium and disequilibrium degassing of a phonolitic melt (Vesuvius AD 79 “white pumice”) simulated by decompression experiments, J. Volcanol. Geoth. Res., 161, 151–164, https://doi.org/10.1016/j.jvolgeores.2006.12.001, 2007.
Keppler, H., Cialdella, L., Couffignal, F., and Wiedenbeck, M.: The solubility of N2 in silicate melts and nitrogen partitioning between upper mantle minerals and basalt, Contrib. Miner. Petrol., 177, 83, https://doi.org/10.1007/s00410-022-01948-z, 2022.
Larsen, J. F.: Heterogeneous bubble nucleation and disequilibrium H2O exsolution in Vesuvius K-phonolite melts, J. Volcanol. Geoth. Res., 175, 278–288, https://doi.org/10.1016/j.jvolgeores.2008.03.015, 2008.
Larsen, J. F. and Gardner, J. E.: Experimental study of water degassing from phonolitic melts: implications for volatile oversaturation during magmatic ascent, J. Volcanol. Geoth. Res., 134, 109–124, https://doi.org/10.1016/j.jvolgeores.2004.01.004, 2004.
Le Gall, N. and Pichavant, M.: Homogeneous bubble nucleation in H2O- and H2O-CO2-bearing basaltic melts: results of high temperature decompression experiments, J. Volcanol. Geoth. Res., 327, 604–621, https://doi.org/10.1016/j.jvolgeores.2016.10.004, 2016.
Lorand, J.-P., Alard, O., and Luguet, A.: Platinum-group element micronuggets and refertilization process in Lherz orogenic peridotite (northeastern Pyrenees, France), Earth Planet. Sc. Lett., 289, 298–310, https://doi.org/10.1016/j.epsl.2009.11.017, 2010.
Mallmann, G. and O'Neill, H. S. C.: The effect of oxygen fugacity on the partitioning of Re between crystals and silicate melt during mantle melting, Geochim. Cosmochim. Ac., 71, 2837–2857, https://doi.org/10.1016/j.gca.2007.03.028, 2007.
Mangan, M. and Sisson, T.: Delayed, disequilibrium degassing in rhyolite magma: decompression experiments and implications for explosive volcanism, Earth Planet. Sc. Lett., 183, 441–455, https://doi.org/10.1016/S0012-821X(00)00299-5, 2000.
Marks, P. L. and Nowak, M.: Vesiculation dynamics – Part 2: Decompression-induced H2O vesicle growth, onset, and progression of coalescence, Eur. J. Mineral., 37, 413–435, https://doi.org/10.5194/ejm-37-413-2025, 2025.
Martel, C. and Schmidt, B. C.: Decompression experiments as an insight into ascent rates of silicic magmas, Contrib. Miner. Petrol., 144, 397–415, https://doi.org/10.1007/s00410-002-0404-3, 2003.
Marxer, H., Bellucci, P., and Nowak, M.: Degassing of H2O in a phonolitic melt: A closer look at decompression experiments, J. Volcanol. Geoth. Res., 297, 109–124, https://doi.org/10.1016/j.jvolgeores.2014.11.017, 2015.
Matthews, W., Linnen, R. L., and Guo, Q.: A filler-rod technique for controlling redox conditions in cold-seal-pressure vessels, Am. Mineral., 88, 701–707, https://doi.org/10.2138/am-2003-0424, 2003.
McCormick, M. P., Thomason, L. W., and Trepte, C. R.: Atmospheric effects of the Mt. Pinatubo 1991 eruption, Nature, 373, 399–404, https://doi.org/10.1038/373399a0, 1995.
McIntosh, I. M., Llewellin, E. W., Humphreys, M. C. S., Nichols, A. R. L., Burgisser, A., Schipper, C. I., and Larsen, J. F.: Distribution of dissolved water in magmatic glass records growth and resorption of bubbles, Earth Planet. Sc. Lett., 401, 1–11, https://doi.org/10.1016/j.epsl.2014.05.037, 2014.
Mongrain, J., Larsen, J. F., and King, P. I.: Rapid water exsolution, degassing, and bubble collapse observed experimentally in K-phonolitic melts, J. Volcanol. Geoth. Res., 173, 178–184, https://doi.org/10.1016/j.jvolgeores.2008.01.026, 2008.
Morgan, G. and London, D.: Effect of current density on the electron microprobe analysis of alkali aluminosilicate glasses, Am. Mineral., 90, 1131–1138, https://doi.org/10.2138/am.2005.1769, 2005.
Mourtada-Bonnefoi, C. C. and Laporte, D.: Experimental study of homogeneous bubble nucleation in rhyolitic magmas, Geophys. Res. Lett., 26, 3505–3508, https://doi.org/10.1029/1999gl008368, 1999.
Mourtada-Bonnefoi, C. C. and Laporte, D.: Homogeneous bubble nucleation in rhyolitic magmas: an experimental study of the effect of H2O and CO2, J. Geophys. Res., 107, 2066, https://doi.org/10.1029/2001JB000290, 2002.
Mujin, M., Nakamura, M., and Miyake, A.: Eruption style and crystal distributions: Crystallization of groundmass nanolites in the 2011 Shinmoedake eruption. Am. Mineral., 102, 2367–2380, https://doi.org/10.2138/am-2017-6052CCBYNCND, 2017.
Murphy, M. D., Sparks, R. S. J., Barkley, J., Carroll, M. R., and Brewer, T. S.: Remobilization of andesite magma by intrusion of mafic magma at the Soufriere Hills Volcano, Montserrat, West Indies, J. Petrol., 41, 21–42, https://doi.org/10.1093/petrology/41.1.21, 2000.
Navon, O. and Lyakhovsky, V.: Vesiculation processes in silicic magmas, in: The Physics of Explosive Volcanic Eruptions, edited by: Gilbert, J. S. and Sparks, R. S. J., Geological Society, London, Special Publications, 145, 27–50, ISBN 1-86239-020-7, 1998.
Nowak, M. and Behrens, H.: An experimental investigation on diffusion of water in haplogranitic melts, Contrib. Miner. Petrol., 126, 365–376, https://doi.org/10.1007/s004100050256, 1997.
Nowak, M., Cichy, S. B., Botcharnikov, R. E., Walker, N., and Hurkuck, W.: A new type of high pressure low-flow metering valve for continuous decompression: First 86 experimental results on degassing of rhyodacitic melts, Am. Mineral., 96, 1373–1380, https://doi.org/10.2138/am.2011.3786, 2011.
Ochs, F. A. and Lange, A. R.: The density of hydrous magmatic liquids, Science, 283, 1314–1317, https://doi.org/10.1126/science.283.5406.1314, 1999.
Ohlhorst, S., Behrens, H., and Holtz, F.: Compositional dependence of molar absorptivities of near-infrared OH− and H2O bands in rhyolitic to basaltic glasses, Chem. Geol., 174, 5–20, https://doi.org/10.1016/S0009-2541(00)00303-X, 2001.
Preuss, O., Marxer, H., Ulmer, S., Wolf, J., and Nowak, M.: Degassing of hydrous trachytic Campi Flegrei and phonolitic Vesuvius melts: Experimental limitations and chances to study homogeneous bubble nucleation, Am. Mineral., 101, 859–875, https://doi.org/10.2138/am-2016-5480, 2016.
Reinig, F., Wacker, L., Jöris, O., Oppenheimer, C., Guidobaldi, G., Nievergelt, D., Adolphi, F., Cherubini, P., Engels, S., Esper, J., Land, A., Lane, C., Pfanz, H., Remmele, S., Sigl, M., Sookdeo, A., and Büntgen, U.: Precise date for the Laacher See eruption synchronizes the Younger Dryas, Nature, 595, 66–69, https://doi.org/10.1038/s41586-021-03608-x, 2021.
Sahagian, D. and Carley, T. L.: Explosive volcanic eruptions and spinodal decomposition: A different approach to deciphering the tiny bubble paradox, Geochem. Geophys. Geosys., 21, 1–9, https://doi.org/10.1029/2019GC008898, 2020.
Scarani, A., Zandonà, A., Di Fiore, F., Valdivia, P., Putra, R., Miyajima, N., Bornhöft, H., Vona, A., Deubener, J., Romano, C., and Di Genova, D.: A chemical threshold controls nanocrystallization and degassing behaviour in basalt magmas, Commun. Earth Environ., 3, 284, https://doi.org/10.1038/s43247-022-00615-2, 2022.
Schmidt, B. C. and Behrens, H.: Water solubility in phonolite melts: Influence of melt composition and temperature, Chem. Geol., 256, 259–268, https://doi.org/10.1016/j.chemgeo.2008.06.043, 2008.
Schmidt, B. C., Holtz, F., and Pichavant, M.: Water solubility in haplogranitic melts coexisting with H2O-H2 fluids, Contrib. Miner. Petrol., 136, 213–224, https://doi.org/10.1007/s004100050533, 1999.
Schmidt, B. C., Blum-Oeste, N., and Flagmeier, J.: Water diffusion in phonolite melts, Geochim. Cosmochim. Ac., 107, 220–230, https://doi.org/10.1016/j.gca.2012.12.044, 2013.
Schmincke, H. U., Park, C., and Harms, E.: Evolution and environmental impacts of the eruption of Laacher See Volcano (Germany) 12,900 a BP, Quaternary Int., 61, 61–72, https://doi.org/10.1016/S1040-6182(99)00017-8, 1999.
Shea, T.: Bubble nucleation in magmas: a dominantly heterogeneous process?, J. Volcanol. Geoth. Res., 343, 155–170, https://doi.org/10.1016/j.jvolgeores.2017.06.025, 2017.
Shea, T., Gurioli, L., Larsen, J. F., Houghton, B. F., Hammer, J. E., and Cashman, K. V.: Linking experimental and natural vesicle textures in Vesuvius 79AD white pumice, J. Volcanol. Geoth. Res., 192, 69–84, https://doi.org/10.1016/j.jvolgeores.2010.02.013, 2010.
Stelling, J., Botcharnikov, R. E., Beermann, O., and Nowak, M.: Solubility of H2O- and chlorine-bearing fluids in basaltic melt of Mount Etna at T=1050–1250 °C and P= 200 MPa, Chem. Geol., 256, 102–110, https://doi.org/10.1016/j.chemgeo.2008.04.009, 2008.
Stolper, E.: Water in silicate glasses: an infrared spectroscopic study, Contrib. Miner. Petrol., 81, 1–17, https://doi.org/10.1007/BF00371154, 1982.
Tomlinson, E. L., Smith, V. C., and Menzies, M. A.: Chemical zoning and open system processes in the Laacher See magmatic system, Contrib. Miner. Petrol., 175, 19, https://doi.org/10.1007/s00410-020-1657-4, 2020.
Toramaru, A.: BND (bubble number density) decompression rate meter for explosive volcanic eruptions, J. Volcanol. Geoth. Res., 154, 303–316, https://doi.org/10.1016/j.jvolgeores.2006.03.027, 2006.
Van den Bogaard, P. and Schmincke, H. U.: The Eruptive Center of the Late Quaternary Laacher See Tephra, Geologische Rundschau, 73, 933–980, https://doi.org/10.1007/BF01820883, 1984.
Van den Bogaard, P. and Schmincke, H. U.: Laacher See Tephra: A widespread isochronous late Quaternary tephra layer in Central and Northern Europe, Geol. Soc. Am. Bull., 96, 1554–1571, https://doi.org/10.1130/0016-7606(1985)96<1554:LSTAWI>2.0.CO;2, 1985.
Webster, J. D., Kinzler, R. J., and Mathez, E. A.: Chloride and water solubility in basalt and andesite melts and implications for magmatic degassing, Geochim. Cosmochim. Ac., 63, 729–738, 1999.
Withers, A. C. and Behrens, H.: Temperature induced changes in the NIR spectra of hydrous albitic and rhyolitic glasses between 300 and 100 K, Phys. Chem. Mineral., 27, 119–132, https://doi.org/10.1007/s002690050248, 1999.
Wörner, G. and Schmincke, H. U.: Mineralogical and chemical zonation of the Laacher see tephra sequence, J. Petrol., 25, 805–835, https://doi.org/10.1093/petrology/25.4.805, 1984a.
Wörner, G. and Schmincke, H. U.: Petrogenesis of the zoned Laacher See Tephra, J. Petrol. 25, 836–851, https://doi.org/10.1093/petrology/25.4.836, 1984b.
Zhang, Y., Xu, Z., and Behrens, H.: Hydrous species geospeedometer in rhyolite: Improved calibration and application, Geochim. Cosmochim. Ac., 64, 3347–3355, https://doi.org/10.1016/S0016-7037(00)00424-5, 2000.
Short summary
We provide new insights into the release of H2O from the phonolitic melt of the Laacher See volcano. Decompression experiments conducted at superliquidus conditions revealed uniformly dispersed vesicles throughout the samples, with extremely high vesicle numbers regardless of the decompression rate. These findings enhance our understanding of volcanic eruptions and might suggest that rapid volatile release due to off-critical spinodal decomposition increases explosive volcanic activity.
We provide new insights into the release of H2O from the phonolitic melt of the Laacher See...
Special issue