Skip to main content

Advertisement

SpringerLink
Log in

Dynamics of explosive volcanism at Unzen volcano: an experimental contribution

  • Research Article
  • Published:
Bulletin of Volcanology Aims and scope Submit manuscript

Abstract

Knowledge of the dynamics of magma fragmentation is necessary for a better understanding of the explosive behaviour of silicic volcanoes. Here we have measured the fragmentation speed and the fragmentation threshold of five dacitic samples (6.7–53.5 vol% open porosity) from Unzen volcano, Kyushu, Japan. The measurements were carried out using a shock-tube-based fragmentation apparatus modified after Alidibirov and Dingwell (1996a,b). The results of the experimental work confirm the dominant influence of porosity on fragmentation dynamics. The velocity of the fragmentation front increases and the value of the fragmentation threshold decreases with increasing porosity. Further, we observe that the fragmentation speed is strongly influenced by the initial pressure difference and the texture of the dacite. At an initial pressure difference of 30 MPa, the fragmentation speed varies from 34 m/s for the least porous sample to 100 m/s for the most porous sample. These results are evaluated by applying them to the 1990–1995 eruptive activity of Unzen volcano. Emplacements of layered lava dome lobes, Merapi-type pyroclastic flows and minor explosive events dominated this eruption. The influence of the fragmentation dynamics on dome collapse and Vulcanian events is discussed.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10

Similar content being viewed by others

References

  • Alidibirov M (1994) A model for viscous magma fragmentation during volcanic blasts. Bull Volcanol 56:459–465

    Article  Google Scholar 

  • Alidibirov M, Dingwell DB (1996a) Magma fragmentation by rapid decompression. Nature 380:146–148

    Article  Google Scholar 

  • Alidibirov M, Dingwell DB (1996b) An experimental facility for investigation of magma fragmentation by rapid decompression. Bull Volcanol 58:411–416

    Article  Google Scholar 

  • Alidibirov M, Dingwell DB (2000) Three fragmentation mechanisms for highly viscous magma under rapid decompression. J Volcanol Geotherm Res 100:413–421

    Article  Google Scholar 

  • Anderson SW, Fink JH, Rose WI (1995) Mount St. Helens and Santiaguito lava domes: the effect of short-term eruption rate on surface texture and degassing processes. J Volcanol Geotherm Res 69:105–116

    Article  Google Scholar 

  • Botcharnikov R, Holtz F, Behrens H, Sato H (2003) Phase equilibrium study and constraints on pre-eruptive conditions of Unzen magmas. Abstract volume of Schwerpunktkolloquium IODP-ICDP, University of Hamburg, Hamburg, 3 pp

  • Cagnoli B, Barmin A, Melnik O, Sparks RSJ (2002) Depressurization of fine powders in a shock tube and dynamics of fragmented magma in volcanic conduits. Earth Planet Sci Lett 6419:1–13

    Google Scholar 

  • Carn SA, Watts RB, Thompson G, Norton GE (2004) Anatomy of a lava dome collapse: the 20 March 2000 event at Soufrière Hills volcano, Montserrat. J Volcanol Geotherm Res 131:241–264

    Article  Google Scholar 

  • Cashman KV, Sturtevant B, Papale P, Navon O (1999) Magmatic fragmentation. In: Sigurdsson H, et al. (eds) Encyclopaedia of volcanoes. Academic Press, San Diego, pp 421–430

    Google Scholar 

  • Dingwell DB (1996) Volcanic dilemma: flow or blow? Science 273:1054–1055

    Article  Google Scholar 

  • Dingwell DB (1998a) Recent experimental progress in the physical description of silicic magma relevant to explosive volcanism. In: Gilbert JS, Sparks RSJ (eds) The physics of explosive volcanic eruptions. Geol Soc Lond Spec Publ 145:9–26

  • Dingwell DB (1998b) Magma degassing and fragmentation: recent experimental advances. In: Freund A, Rosi M (eds) From magma to tephra. Modelling physical processes of explosive volcanic eruptions. Developments in volcanology. Elsevier, Amsterdam, pp 1–23

    Google Scholar 

  • Druitt TH, Young SR, Baptie B, Bonadonna C, Calder ES, Clarke AB, Cole PD, Harford CL, Herd RA, Luckett R, Ryan G, Voight B (2002) Episodes of cyclic Vulcanian explosive activity with fountain collapse at Soufrière Hills Volcano, Montserrat. In: Druitt TH, Kokelaar BP (eds) The Eruption of Soufrière Hills Volcano, Montserrat, from 1995 to 1999. Geol Soc Lond Mem 21:281–306

  • Eichelberger JC, Carrigan HR, Westrich HR, Price RH (1986) Nonexplosive silicic volcanism. Nature 323:595–602

    Article  Google Scholar 

  • Fink J, Kieffer SW (1993) Estimate of pyroclastic flow velocities resulting from explosive decompression of lava domes. Nature 363:612–615

    Article  Google Scholar 

  • Fujii T, Nakada S (1999) The 15 September 1991 pyroclastic flows at Unzen Volcano (Japan): a flow model for associated ash-cloud surges. J Volcanol Geotherm Res 89:159–172

    Article  Google Scholar 

  • Gonnermann HM, Manga M (2003) Explosive volcanism may not be an inevitable consequence of magma fragmentation. Nature 426:432–435

    Article  Google Scholar 

  • Goto A (1999) A new model for volcanic earthquake at Unzen Volcano; melt rupture model. Geophys Res Lett 26(16):2541–2544

    Article  Google Scholar 

  • Heiken G, Wohletz K (1991) Fragmentation processes in explosive volcanic eruptions. In: Fisher RV, Smith G (eds) Sedimentation in volcanic settings. Soc Sediment Geol Spec Pub 45:19–26

  • Ichihara M, Rittel D, Sturtevant B (2002) Fragmentation of a porous viscoelastic material: implications to magma fragmentation. J Geophys Res 107(B10):2229, DOI:10.1029/2001JB000591

    Google Scholar 

  • Kaminski E, Jaupart C (1998) The size distribution of pyroclasts and the fragmentation sequence in explosive volcanic eruptions. J Geophys Res 103:29759–29779

    Article  Google Scholar 

  • Kennedy B, Spieler O, Scheu B, Kueppers U, Taddeucci J, Dingwell DB (2005) Conduit implosion during Vulcanian eruptions. Geology 33(7):581–584

    Article  Google Scholar 

  • Kueppers U, Scheu B, Spieler O, Dingwell DB (2005) Field based density measurements as tool to recalculate pre-eruption dome structure: set-up and first results. J Volcanol Geotherm Res 141:65–75

    Article  Google Scholar 

  • Kusakabe M, Sato H, Nakada S, Kitamura T (1999) Water contents and hydrogen isotopic ratios of rocks and minerals from the 1991 eruption of Unzen volcano, Japan. J Volcanol Geotherm Res 89:231–242

    Article  Google Scholar 

  • Lane SJ, Chouet BA, Phillips JC, Dawson P, Ryan GA, Hurst E (2001) Experimental observations of pressure oscillations and flow regimes in an analogue volcanic system. J Geophys Res 106:6461–6476

    Article  Google Scholar 

  • Mader HM (1998) Conduit flow and fragmentation. In: Gilbert JS, Sparks RSJ (eds) The physics of explosive volcanic eruptions. Geol Soc Lond Spec Publ 145:51–71

  • Mader HM, Zhang Y, Phillips JC, Sparks RSJ, Sturtevant B, Stolper E (1994) Experimental simulations of explosive degassing of magma. Nature 372:85–88

    Article  Google Scholar 

  • Mader HM, Phillips JC, Sparks RSJ, Sturtevant B (1996) Dynamics of explosive degassing of magma: observations of fragmenting two-phase flow. J Geophys Res 101:5547–5560

    Article  Google Scholar 

  • Martel C, Dingwell DB, Spieler O, Pichavant M, Wilke M (2000) Foaming and fragmentation in silicic melts: an experimental study. Earth Planet Sci Lett 178:47–58

    Article  Google Scholar 

  • Melnik OE (2000) Dynamics of two-phase conduit flow of high-viscosity gas-saturated magma: large variations of sustained explosive eruption intensity. Bull Volcanol 62:153–170

    Article  Google Scholar 

  • Melnik O, Sparks RSJ (1999) Nonlinear dynamics of lava dome extrusion. Nature 402:37–41

    Article  Google Scholar 

  • Melnik O, Sparks RSJ (2002) Modelling of conduit flow dynamics during explosive activity at Soufrière Hills Volcano, Montserrat. In: Druitt TH, Kokelaar BP (eds) The eruption of Soufrière Hills Volcano, Montserrat, from 1995 to 1999. Geol Soc Lond Mem 21:307–317

  • Mueller S, Melnik O, Spieler O, Scheu B, Dingwell DB (2005) Permeability and degassing of dome lavas undergoing rapid decompression: an experimental determination. Bull Volcanol 67:526–538

    Article  Google Scholar 

  • Murase AR, McBirney T, Melson WG (1985) Viscosity of the dome of Mount St. Helens. J Volcanol Geotherm Res 24:193–204

    Article  Google Scholar 

  • Nakada S (1992) Lava domes and pyroclastic flows of the 1991–1992 eruption at Unzen volcano. In: Yanagi T, Okada H, Ohta K (eds) Unzen volcano, the 1990–1992 eruption. The Nishinippon and Kyushu University Press, Fukuoka, Japan, pp 56–66

  • Nakada S, Motomura Y (1999) Petrology of the 1991–1995 eruption at Unzen: effusion pulsation and groundmass crystallization. J Volcanol Geotherm Res 89:173–196

    Article  Google Scholar 

  • Nakada S, Shimizu H, Ohta K (1999) Overview of the 1990–1995 eruption at Unzen volcano. J Volcanol Geotherm Res 89:1–22

    Article  Google Scholar 

  • Nakada S, Sakuma S, Uto K, Shimizu H, Eichelberger JC (2004) Real images of magmatic conduit: progress of the conduit drilling in Unzen. EOS Trans. AGU 85, Fall Meeting Suppl.:V24B-06

  • Nonaka M, Nakada S, Goto Y (2004) Emplacement process of the 1991–1995 dome at Unzen volcano, Japan. EOS Trans. AGU 85, Fall Meeting Suppl.:V33D–1486

  • Papale P (1999) Strain-induced magma fragmentation in explosive eruptions. Nature 397:425–428

    Article  Google Scholar 

  • Phillips JC, Lane SJ, Lejeune A-M, Hilton M (1995) Gum-rosin-acetone system as an analogue to the degassing behaviour of hydrated magmas. Bull Volcanol 57:263–268

    Google Scholar 

  • Sato H, Fujii T, Nakada S (1992) Crumbling of dacite dome lava and generation of pyroclastic flows at Unzen volcano. Nature 360:664–666

    Article  Google Scholar 

  • Smith JV, Miyake Y, Oikawa T (2001) Interpretation of porosity in dacite lava domes as ductile-brittle failure textures. J Volcanol Geotherm Res 112:25–35

    Article  Google Scholar 

  • Sparks RSJ (1978) The dynamics of bubble formation and growth in Magmas: a review and analysis. J Volcanol Geotherm Res 3:1–37

    Article  Google Scholar 

  • Sparks RSL (1994) Comment on ”Dynamics of diffusive bubble growth in magmas: isothermal case” by A.A. Proussevitch, D.L Sahagian, and A.T. Anderson. J Geophys Res 99:17827–17828

    Article  Google Scholar 

  • Sparks RSJ, Barclay J, Calder ES et al (2002) Generation of a debris avalanche and violent pyroclastic density current on 26 December (Boxing Day) at Soufrière Hills Volcano. Montserrat. In: Druitt TH, Kokelaar BP (eds) The eruption of Soufrière Hills Volcano, Montserrat, from 1995 to 1999. Geol Soc Lond Mem 21:409–434

  • Spieler O, Alidibirov M, Dingwell DB (2003) Grain-size characteristics of experimental pyroclasts of 1980 Mount St. Helens cryptodome dacite: effects of pressure drop and temperature. Bull Volcanol 65:90–104

    Google Scholar 

  • Spieler O, Dingwell DB, Alidibirov M (2004a) Magma fragmentation speed: an experimental determination. J Volcanol Geotherm Res 129:109–123

    Article  Google Scholar 

  • Spieler O, Kennedy B, Kueppers U, Dingwell DB, Scheu B, Taddeucci J (2004b) The fragmentation threshold of pyroclastic rocks. Earth Planet Sci Lett 226:139–148

    Article  Google Scholar 

  • Sugioka I, Bursik M (1995) Explosive fragmentation of erupting magma. Nature 373:689–692

    Article  Google Scholar 

  • Tuffen H, Dingwell DB, Pinkerton H (2003) Repeated fracture and healing of silicic magma generate flow banding and earthquakes? Geology 31(12):1089–1092

    Article  Google Scholar 

  • Ui T, Matsuwo N, Suita M, Fujinawa A (1999) Generation of block and ash flows during the 1990–1995 eruption of Unzen Volcano, Japan. J Volcanol Geotherm Res 89:123–137

    Article  Google Scholar 

  • Umakoshi K, Shimizu H, Matsuwo N, Otha K (1992) Surface temperature measurements of lava domes and pyroclastic flows by infrared thermal video system. In: Yanagi T, Okada H, Ohta K (eds) Unzen Volcano, the 1990–1992 eruption. The Nishinippon and Kyushu University Press, Fukuoka, pp 44–48

    Google Scholar 

  • Umakoshi K, Shimizu H, Matsuwo N (2001) Volcano-tectonic seismicity at Unzen volcano, Japan 1985–1999. J Volcanol Geotherm Res 112:117–131

    Article  Google Scholar 

  • Woods AW, Sparks RSJ, Ritchie LJ, Batey J, Gladstone C, Bursik MI (2002) The explosive decompression of a pressurized volcanic dome: the 26 December 1997 collapse and explosion of Soufrière Hills Volcano, Montserrat. In: Druitt TH, Kokelaar BP (eds) The Eruption of Soufrière Hills Volcano, Montserrat, from 1995 to 1999. Geol Soc Lond Mem 21:595–602

  • Yanagi T, Okada H, Ohta K (1992) Unzen Volcano, the 1990–1992 eruption. The Nishinippon and Kyushu University Press, Fukuoka, 137 pp

  • Young SR, Sparks RSJ, Aspinall WP, Lynch LL, Miller AD, Robertson REA, Shepherd JB (1998) Overview of the eruption of Soufrière Hills Volcano, Montserrat, 18 July 1995 to December 1997. Geophys Res Lett 25(18):3389–3392

    Article  Google Scholar 

  • Zhang Y, Sturtevant B, Stolper EM (1997) Dynamics of gas-driven eruptions: experimental simulations using CO2-H2O-polymer system. J Geophys Res 102:3077–3096

    Article  Google Scholar 

  • Zhang Y (1999) A criterion for the fragmentation of bubbly magma based on brittle failure theory. Nature 402:648–650

    Article  Google Scholar 

  • Zimanowski B, Büttner R, Lorenz V, Häfele H-G (1997) Fragmentation of basaltic melt in the course of explosive volcanism. J Geophys 102(B1):803–814

    Google Scholar 

Download references

Acknowledgements

This work was partially funded by the project DI 431-20-1 from the German Science Foundation (DFG). The fieldwork and sampling were carried out in 2000 and 2001 together with Ulrich Kueppers. Joachim Gottsmann (Institute of Earth Sciences “Jaume Almera”, Barcelona, Spain) drilled the layered block during the 2000 field campaign. We would like to thank Ben Kennedy, Ulli Kueppers, Sebastian Mueller and Alex Nichols for helpful discussions, Setsuya Nakada and Hiroshi Shimizu for providing us with qualitative information. Shimabara Earthquake and Volcano Observatory (SEVO) permitted access to the Unzen National Park and provided logistic support during fieldwork. Two anonymous reviewers and Andy Woods contributed helpful suggestions that improved the manuscript.

Author information

Authors and Affiliations

  1. Earth and Environmental Sciences, University of Munich, Theresienstr. 41/III, 80333, Munich, Germany

    Bettina Scheu, Oliver Spieler & Donald B. Dingwell

  2. Earthquake Research Institute, University of Tokyo, 113-0032, Tokyo, Japan

    Bettina Scheu

Authors
  1. Bettina Scheu
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Oliver Spieler
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Donald B. Dingwell
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Bettina Scheu.

Additional information

Editorial responsibility: A. Woods

Rights and permissions

Reprints and permissions

About this article

Cite this article

Scheu, B., Spieler, O. & Dingwell, D.B. Dynamics of explosive volcanism at Unzen volcano: an experimental contribution. Bull Volcanol 69, 175–187 (2006). https://doi.org/10.1007/s00445-006-0066-5

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00445-006-0066-5

Keywords

Search

Navigation