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Bulletin of Volcanology

, 77:99 | Cite as

Thermal state and implications for eruptive styles of the intra-Plinian and climactic ignimbrites of the 4.6 ka Fogo A eruption sequence, São Miguel, Azores

  • A. PensaEmail author
  • G. Giordano
  • R. A. F. Cas
  • M. Porreca
Research Article

Abstract

The 4.6 ka Fogo A Plinian eruption was a caldera-forming volcanic event on São Miguel Island, Azores. The deposit succession is very complex, composed of a thick trachytic Plinian fallout deposit interstratified with two intra-Plinian ignimbrites (named “pink ignimbrite” and “black ignimbrite” sequentially). The succession ends with a main ignimbrite (named “dark brown ignimbrite”), which represents the deposit of complete collapse of the eruption column and the end of the eruption. In this work, emplacement temperatures of the three ignimbrites are estimated by study of partial thermal remanent magnetization (pTRM) of lithic clasts. A total of 140 oriented lithic clasts were collected from 15 localities distributed along the northern and southern flanks of Fogo volcano. The paleomagnetic data reveal different emplacement temperatures and thermal histories that were experienced by each ignimbrite. The results indicate the presence of five different paleomagnetic behaviours that suggest emplacement temperatures of 350–400 °C for the first (pink) intra-Plinian ignimbrite, temperatures higher than 580–600 °C for the second (black) intra-Plinian ignimbrite and 250–370 °C for the last (dark brown) climactic ignimbrite. The thermal history experienced by each pyroclastic flow and its ignimbrite deposit was also assessed by the use of the magnetite-ilmenite geothermometer to determine the pre-eruptive magma temperature (estimated to be around 900 °C). We interpret the different emplacement temperatures of the Fogo A ignimbrites as being due to a combination of factors. These include (i) collapse from different heights of the eruption column and the resultant different amounts of air entrainment into the gas-particle mixture, (ii) variable content of lithic clasts and (iii) different types of juvenile clasts in the ignimbrites.

Keywords

Ignimbrite Emplacement temperature Thermal remanent magnetization Fogo A eruption Heat dissipation 

Notes

Acknowledgments

We would like to thank Roma Tre University for the use of the paleomagnetic facilities. We are particularly grateful to Prof. M. Mattei and Dr. F. Cifelli for their support during paleomagnetic analysis. We express appreciation to CVARG Centre, University of Azores, São Miguel, for the kind hospitality during the field work. We also would like to thank the reviewer Lucia Gurioli and the editor Steve Self for the very helpful comments that have improved the manuscript. This research forms part of the PhD research of A. Pensa at Monash University, supported by discretionary research funds of Emeritus Professor R.A.F. Cas.

Supplementary material

445_2015_983_Fig7_ESM.gif (55 kb)
A 1

1. Paleomagnetic site FO-06: clasts FO-06-01, FO-06-03, FO-06-05, FO-06-07, FO-06-08 display one single magnetic component; stable up to temperatures of 440° and 480 °C; the remaining samples FO-06-02, FO-06-04 FO-06-06 show two magnetic components stable up to temperatures of 350° and 400 °C (GIF 55 kb)

445_2015_983_Fig8_ESM.gif (50 kb)
A 1

1. Paleomagnetic site FO-06: clasts FO-06-01, FO-06-03, FO-06-05, FO-06-07, FO-06-08 display one single magnetic component; stable up to temperatures of 440° and 480 °C; the remaining samples FO-06-02, FO-06-04 FO-06-06 show two magnetic components stable up to temperatures of 350° and 400 °C (GIF 55 kb)

445_2015_983_Fig9_ESM.gif (59 kb)
A 1

1. Paleomagnetic site FO-06: clasts FO-06-01, FO-06-03, FO-06-05, FO-06-07, FO-06-08 display one single magnetic component; stable up to temperatures of 440° and 480 °C; the remaining samples FO-06-02, FO-06-04 FO-06-06 show two magnetic components stable up to temperatures of 350° and 400 °C (GIF 55 kb)

445_2015_983_Fig10_ESM.gif (60 kb)
A 1

1. Paleomagnetic site FO-06: clasts FO-06-01, FO-06-03, FO-06-05, FO-06-07, FO-06-08 display one single magnetic component; stable up to temperatures of 440° and 480 °C; the remaining samples FO-06-02, FO-06-04 FO-06-06 show two magnetic components stable up to temperatures of 350° and 400 °C (GIF 55 kb)

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445_2015_983_Fig11_ESM.gif (53 kb)
B 1

1. Paleomagnetic site FO-10: clasts FO-10-01, FO-10-02, FO-10-03, FO-10-05, FO-10-07 FO-10-08 display one single magnetic component; stable up 480° to 580 °C. One sample (FO-10-04) has been discarded because it shows unstable behaviour (GIF 53 kb)

445_2015_983_Fig12_ESM.gif (66 kb)
B 1

1. Paleomagnetic site FO-10: clasts FO-10-01, FO-10-02, FO-10-03, FO-10-05, FO-10-07 FO-10-08 display one single magnetic component; stable up 480° to 580 °C. One sample (FO-10-04) has been discarded because it shows unstable behaviour (GIF 53 kb)

445_2015_983_Fig13_ESM.gif (56 kb)
B 1

1. Paleomagnetic site FO-10: clasts FO-10-01, FO-10-02, FO-10-03, FO-10-05, FO-10-07 FO-10-08 display one single magnetic component; stable up 480° to 580 °C. One sample (FO-10-04) has been discarded because it shows unstable behaviour (GIF 53 kb)

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445_2015_983_MOESM7_ESM.eps (1.6 mb)
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445_2015_983_Fig14_ESM.gif (49 kb)
C 1

1. Paleomagnetic site FO-11: clasts FO-11-02, FO-11-05, FO-11-06, FO-11-07, FO-11-08 have a single magnetic component, which is stable up to temperatures of 400° and 520 °C. Of the remaining samples, FO-11-03, show two magnetic components that are stable up to temperatures between 300 °C and 340 °C. Two samples (FO-11-01 and FO-11-04) have been rejected because it displays unstable behaviour (GIF 48 kb)

445_2015_983_Fig15_ESM.gif (59 kb)
C 1

1. Paleomagnetic site FO-11: clasts FO-11-02, FO-11-05, FO-11-06, FO-11-07, FO-11-08 have a single magnetic component, which is stable up to temperatures of 400° and 520 °C. Of the remaining samples, FO-11-03, show two magnetic components that are stable up to temperatures between 300 °C and 340 °C. Two samples (FO-11-01 and FO-11-04) have been rejected because it displays unstable behaviour (GIF 48 kb)

445_2015_983_Fig16_ESM.gif (55 kb)
C 1

1. Paleomagnetic site FO-11: clasts FO-11-02, FO-11-05, FO-11-06, FO-11-07, FO-11-08 have a single magnetic component, which is stable up to temperatures of 400° and 520 °C. Of the remaining samples, FO-11-03, show two magnetic components that are stable up to temperatures between 300 °C and 340 °C. Two samples (FO-11-01 and FO-11-04) have been rejected because it displays unstable behaviour (GIF 48 kb)

445_2015_983_Fig17_ESM.gif (60 kb)
C 1

1. Paleomagnetic site FO-11: clasts FO-11-02, FO-11-05, FO-11-06, FO-11-07, FO-11-08 have a single magnetic component, which is stable up to temperatures of 400° and 520 °C. Of the remaining samples, FO-11-03, show two magnetic components that are stable up to temperatures between 300 °C and 340 °C. Two samples (FO-11-01 and FO-11-04) have been rejected because it displays unstable behaviour (GIF 48 kb)

445_2015_983_Fig18_ESM.gif (62 kb)
C 1

1. Paleomagnetic site FO-11: clasts FO-11-02, FO-11-05, FO-11-06, FO-11-07, FO-11-08 have a single magnetic component, which is stable up to temperatures of 400° and 520 °C. Of the remaining samples, FO-11-03, show two magnetic components that are stable up to temperatures between 300 °C and 340 °C. Two samples (FO-11-01 and FO-11-04) have been rejected because it displays unstable behaviour (GIF 48 kb)

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References

  1. Andersen DJ, Lindsley DH (1985) New models for the Ti-magnetite/ilmenite geothermometer and oxygen barometer. Abstract AGU, meeting Eos transactions. Am Geophys Union 66(18):416Google Scholar
  2. Banks NG, Hoblitt RP (1996) Direct temperature measurements of deposits, Mount St. Helens, Washington, 1980–1981. USGS Professional Paper 1387Google Scholar
  3. Bardot L, McClelland E (2000) The reliability of emplacement temperature estimates using palaeomagnetic methods, a case study from Santorini, Greece. Geophys J Int 143(1):39–51CrossRefGoogle Scholar
  4. Booth B, Croasdale R, Walker GPL (1978) A quantitative study of five thousand years of volcanism on Sao Miguel, Azores. Philos Trans R Soc A Math Phys Eng Sci 288(1352):271–319CrossRefGoogle Scholar
  5. Burden RE, Chen L, Phillips JC (2013) A statistical method for determining the volume of volcanic fall deposits. Bull Volcanol 75(6):1–10CrossRefGoogle Scholar
  6. Bursik MI, Woods AW (1996) The dynamics and thermodynamics of volcanic ash flows. Bull Volcanol 58(2):175–193CrossRefGoogle Scholar
  7. Bursik MI, Sparks RSJ, Gilbert JS, Carey SN (1992) Sedimentation of tephra by volcanic plumes: 1. Theory and its comparison with a study of the Fogo A Plinian deposit, Sao Miguel (Azores). Bull Volcanol 54(4):329–344CrossRefGoogle Scholar
  8. Butler RF (1992) Paleomagnetism: magnetic domains to geologic terranes. Blackwell Scientific, Oxford, p 238Google Scholar
  9. Büttner R, Dellino P, Zimanowski B (1999) Identifying magma–water interaction from the surface features of ash particles. Nature 401:688–690CrossRefGoogle Scholar
  10. Capaccioni B, Forjaz VH, Martini M (1994) Pyroclastic flow hazard at Agua de Pau volcano (São Miguel island, Azores archipelago) inferred from the Fogo A eruptive unit. Acta Vulcanol 5:41–48Google Scholar
  11. Caricchi C, Vona A, Corrado S, Giordano G, Romano C (2014) 79 AD Vesuvius PDC deposits’ temperatures inferred from optical analysis on woods charred in-situ in the Villa dei Papiri at Herculaneum (Italy). J Volcanol Geotherm Res 289:14–25CrossRefGoogle Scholar
  12. Cas RAF, Wright JV (1988) Volcanic Successions: Modern and Ancient: Chapman & Hall, London, pp. 528Google Scholar
  13. Chadima M, Hrouda F (2006) Remasoft 3.0 a user-friendly paleomagnetic data browser and analyser. Trav Geophys XXVII:20–21Google Scholar
  14. Cioni R, Gurioli L, Lanza R, Zannella E  (2004) Temperatures of the A.D. 79 pyroclastic density current deposits (Vesuvius, Italy). J Geophys Res 109(B02):1–18Google Scholar
  15. Dartevelle S, Rose WI, Stix J, Kelfoun K, Vallance JW (2004) Numerical modeling of geophysical granular flows: 2. Computer simulations of Plinian clouds and pyroclastic flows and surges. Geochem Geophys Geosyst 5(8):Q08004Google Scholar
  16. Di Vito MA, Zanella E, Gurioli L, Lanza R, Sulpizio R, Bishop J, Tema E, Boenzi G, Laforgia E (2009) The afragola settlement near Vesuvius, Italy: the destruction and abandonment of a Bronze Age village revealed by archaeology, volcanology and rock-magnetism. Earth Planet Sci Lett 277(3–4):408–421CrossRefGoogle Scholar
  17. Dobran F (1992) Non-equilibrium flow in volcanic conduits and application to the eruptions of Mt. St. Helens on May 18, 1980, and Vesuvius in AD 79. J Volcanol Geotherm Res 49(3–4):285–311CrossRefGoogle Scholar
  18. Fisher RA (1953) Dispersion on a sphere. Proc R Soc Lond 217:295–305CrossRefGoogle Scholar
  19. Gandino A, Guidi M, Merlo C, Mete L, Rossi R, Zan L (1985) Preliminary model of the Ribeira Grande geothermal field (Azores islands). Geothermics 14(1):91–105CrossRefGoogle Scholar
  20. Giordano D, Nichols ARL, Dingwell DB (2005) Glass transition temperatures of natural hydrous melts: a relationship with shear viscosity and implications for the welding process. J Volcanol Geotherm Res 142(1):105–118CrossRefGoogle Scholar
  21. Gurioli L, Pareschi MT, Zanella E, Lanza R, Deluca E, Bisson M (2005) Interaction of pyroclastic density currents with human settlements: evidence from ancient Pompeii. Geology 33(6):441–444CrossRefGoogle Scholar
  22. Gurioli L, Zanella E, Pareschi MT, Lanza R (2007) Influences of urban fabric on pyroclastic density currents at Pompeii (Italy): flow direction and deposition. J Geophys Res 112(B05):213Google Scholar
  23. Koyaguchi T, Woods AW (1996) On the formation of eruption columns following explosive mixing of magma and surface-water. J Geophys Res Solid Earth 101(B3):5561–5574CrossRefGoogle Scholar
  24. Lepage LD (2003) ILMAT: an excel worksheet for ilmenite–magnetite geothermometry and geobarometry. Comput Geosci 29(5):673–678CrossRefGoogle Scholar
  25. Lesti C, Porreca M, Giordano G, Mattei M, Cas RAF, Write HMN, Folkes CB, Viramonte JG (2011) High-temperature emplacement of the Cerro Galan and toconquis group ignimbrites (puna plateau, NW Argentina) determined by TRM analyses. Bull Volcanol 73(10):1535–1565CrossRefGoogle Scholar
  26. Martí J, Diez-Gil JL, Ortiz R (1991) Conduction model for the thermal influence of lithic clasts in mixtures of hot gases and ejecta. J Geophys Res Solid Earth 96:21879–21885CrossRefGoogle Scholar
  27. McClelland E, Wilson CJN, Bardot L (2004) Palaeotemperature determinations for the 1.8-ka Taupo ignimbrite, New Zealand, and implications for the emplacement history of a high-velocity pyroclastic flow. Bull Volcanol 66(6):492–513CrossRefGoogle Scholar
  28. Moore RB (1990) Volcanic geology and eruption frequency, Silo Miguel, Azores. Bull Volcanol 52:602–614CrossRefGoogle Scholar
  29. Mukherjee A (1967) Role of fractional crystallization in the descent. Basalt-Trachyte Contribut Mineral Petrol 16(2):139–148CrossRefGoogle Scholar
  30. Neri A, Esposti Ongaro T, Macedonio G, Gidaspow D (2003) Multiparticle simulation of collapsing volcanic columns and pyroclastic flow. J Geophys Res 108(B4):2202CrossRefGoogle Scholar
  31. Ogden DE, Glatzmaier GA, Wohletz KH (2008) Effects of vent overpressure on buoyant eruption columns: implications for plume stability. Earth Planet Sci Lett 268(3):283–292CrossRefGoogle Scholar
  32. Paterson GA, Roberts AP, Mac Niocaill C, Muxworthy AR, Gurioli L, Viramonte JG, Navarro C, Weider S (2010) Paleomagnetic determination of emplacement temperatures of pyroclastic deposits: an under-utilized tool. Bull Volcanol 72(3):309–330CrossRefGoogle Scholar
  33. Pensa A, Porreca M, Corrado S, Giordano G, Cas RA (2015a) Calibrating the TRM and charcoal reflectance (Ro%) methods to determine the emplacement temperature of ignimbrites: Fogo A sequence, São Miguel, Azores, Portugal, as a case study. Bull Volcanol 77(3):1–19CrossRefGoogle Scholar
  34. Pensa A, Cas RA, Giordano G, Porreca M, Wallenstein N (2015b) Transition from steady to unsteady Plinian eruption column: the VEI 5, 4.6 ka Fogo A Plinian eruption, São Miguel, Azores. J Volcanol Geotherm Res 305:1–18CrossRefGoogle Scholar
  35. Porreca M, Giordano G, Mattei M, Musacchio P (2006) Evidence of two Holocene phreatomagmatic eruptions at Stromboli volcano (Aeolian Islands) from paleomagnetic data. Geophys Res Lett 33(21), L21316CrossRefGoogle Scholar
  36. Porreca M, Mattei M, MacNiocaill C, Giordano G, McClelland E, Funiciello R (2008) Paleomagnetic evidence for low-temperature emplacement of the phreatomagmatic Peperino Albano ignimbrite (Colli Albani volcano, Central Italy). Bull Volcanol 70(7):877–893CrossRefGoogle Scholar
  37. Powell R, Powell M (1977) Geothermometry and oxygen barometry using coexisting iron-titanium oxides: a reappraisal. Mineral Mag 41(318):257–263CrossRefGoogle Scholar
  38. Rowley PD, Kuntz MA, Macleod NS (1981) Pyroclastic flow deposits. In: Lipman PW, Mullineaux DR (eds) The 1980 Eruptions of Mount St Helens, 1250th edn, US Geological Survey. Professional Papers, Washington, pp 489–512Google Scholar
  39. Shea T, Gurioli L, Houghton BF, Cioni R, Cashman KV (2011) Column collapse and generation of pyroclastic density currents during the A.D. 79 eruption of Vesuvius: the role of pyroclast density. Geology 39(7):695–698CrossRefGoogle Scholar
  40. Shea T, Gurioli L, Houghton BF (2012) Transitions between fall phases and pyroclastic density currents during the AD 79 eruption at Vesuvius: building a transient conduit model from the textural and volatile record. Bull Volcanol 74(10):2363–2381CrossRefGoogle Scholar
  41. Shotton FW, Blundell DJ, Williams REG (1968) Birmingham University radiocarbon dates II. Radiocarbon 10:200–206Google Scholar
  42. Shotton FW, Blundell DJ, Williams REG (1969) Birmingham University radiocarbon dates III. Radiocarbon 11:263–270Google Scholar
  43. Sparks RSJ, Wilson L (1976) A model for the formation of ignimbrite by gravitational column collapse. J Geol Soc Lond 132(4):441–451CrossRefGoogle Scholar
  44. Sparks RSJ, Bursik MI, Carey SN, Gilbert JS, Glaze H, Sigurdsson H, Woods AW (1997) Volcanic plumes. Wiley, New York, p 590Google Scholar
  45. Spencer KJ, Lindsley DH (1981) A solution model for coexisting iron-titanium oxides. Am Mineral 66(11–12):1189–1201Google Scholar
  46. Thomas R, Sparks R (1992) Cooling of tephra during fallout from eruption columns. Bull Volcanol 54(7):542–553CrossRefGoogle Scholar
  47. Walker GPL, Croasdale R (1970) Two Plinian-type eruptions in the Azores. J Geol Soc Lond 127:17–55CrossRefGoogle Scholar
  48. Wallenstein N (1999) Estudo da história recente e do comportamento eruptivo do vulcão do Fogo. In: SMiguel A (ed) A valiação preliminar do hazard. PhD thesis. Departamento de Geociências Universidades dos Açores, São Miguel Island (Portugal)Google Scholar
  49. Wilson L, Sparks RSJ, Huang TC, Watkins ND (1978) The control of volcanic column heights by eruption energetics and dynamics. J Geophys Res 83(B04):1829–1836CrossRefGoogle Scholar
  50. Wilson L, Sparks RSJ, Walker GPL (1980) Explosive volcanic eruptions-IV. The control of magma properties and conduit geometry on eruption column behaviour. Geophys J R Astron Soc 63(1):117–148CrossRefGoogle Scholar
  51. Wohletz KH (1983) Mechanics of hydrovolcanic pyroclast formation: grain-size, scanning microscopy, and experimental studies. J Volcanol Geotherm Res 17:31–63CrossRefGoogle Scholar
  52. Woods AW, Bursik M (1991) Particle fall-out, thermal disequilibrium and volcanic plumes. Bull Volcanol 53(7):559–570CrossRefGoogle Scholar
  53. Zanella E, Gurioli L, Pareschi MT, Lanza R (2007) Influences of urban fabric on pyroclastic density currents at Pompeii (Italy), part II: temperature of the deposits and hazard implication. J Geophys Res 112(B05):214Google Scholar
  54. Zanella E, Gurioli L, Lanza R, Sulpizio R, Bontempi M (2008) Deposition temperature of the AD 472 pollena pyroclastic density currents deposits, Somma-Vesuvius, Italy. Bull Volcanol 70(10):1237–1248CrossRefGoogle Scholar
  55. Zanella E, Sulpizio R, Gurioli L, Lanza R (2014) Temperatures of the pyroclastic density currents deposits emplaced in the last 22 kyr at Somma-Vesuvius (Italy). In: Ort MH, Porreca M, Geissman JW (eds) The use of palaeomagnetism and rock magnetism to understand volcanic processes. Geological society, vol 396, 1. Special Publications, London, pp 13–33Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • A. Pensa
    • 1
    Email author
  • G. Giordano
    • 2
  • R. A. F. Cas
    • 1
  • M. Porreca
    • 3
    • 4
  1. 1.Monash UniversityClaytonAustralia
  2. 2.Roma Tre UniversityRomeItaly
  3. 3.Department of Physics and GeologyUniversity of PerugiaPerugiaItaly
  4. 4.Centro de Vulcanologia e Avaliação de Riscos Geológicos (CVARG), Departamento de GeociênciasUniversidade dos AçoresPonta DelgadaPortugal

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