Bulletin of Volcanology

, Volume 70, Issue 9, pp 1069–1086 | Cite as

Voluminous lava flows at Oldoinyo Lengai in 2006: chronology of events and insights into the shallow magmatic system

  • Matthieu Kervyn
  • Gerald G. J. Ernst
  • Jurgis Klaudius
  • Jörg Keller
  • François Kervyn
  • Hannes B. Mattsson
  • Frederic Belton
  • Evelyne Mbede
  • Patric Jacobs
Research Article

Abstract

The largest natrocarbonatite lava flow eruption ever documented at Oldoinyo Lengai, NW Tanzania, occurred from March 25 to April 5, 2006, in two main phases. It was associated with hornito collapse, rapid extrusion of lava covering a third of the crater and emplacement of a 3-km long compound rubbly pahoehoe to blocky aa-like flow on the W flank. The eruption was followed by rapid enlargement of a pit crater. The erupted natrocarbonatite lava has high silica content (3% SiO2). The eruption chronology is reconstructed from eyewitness and news media reports and Moderate Resolution Imaging Spectroradiometer (MODIS) satellite data, which provide the most reliable evidence to constrain the eruption’s onset and variations in activity. The eruption products were mapped in the field and the total erupted lava volume estimated at 9.2 ± 3.0 × 105 m3. The event chronology and field evidence are consistent with vent construct instability causing magma mixing and rapid extrusion from shallow reservoirs. It provides new insights into and highlights the evolution of the shallow magmatic system at this unique natrocarbonatite volcano.

Keywords

Oldoinyo Lengai Hornito collapse Lava flow Collapse pit MODLEN 

References

  1. Carslaw HS, Jaeger JC (1959) Conduction of heat in solids. Oxford Univ Press, New YorkGoogle Scholar
  2. Church AA, Jones AP (1994) Hollow natrocarbonatite lapilli from the 1992 eruption of Oldoinyo Lengai, Tanzania. J Geol Soc London 151:59–63CrossRefGoogle Scholar
  3. Church AA, Jones AP (1995) Silicate-carbonate immiscibility at Oldoinyo-Lengai. J Petrol 36:869–889Google Scholar
  4. Dawson JB (1998) Peralkaline nephelinite–natrocarbonatite relationships at Oldoinyo Lengai, Tanzania. J Petrol 39:2077–2094CrossRefGoogle Scholar
  5. Dawson JB, Pinkerton H, Norton GE, Pyle DM (1990) Physicochemical properties of alkali carbonatite lavas: data from the 1988 eruption of Oldoinyo Lengai, Tanzania. Geology 18:260–263CrossRefGoogle Scholar
  6. Dawson JB, Smith JV, Steele IM (1992) 1966 ash eruption of the carbonatite volcano Oldoinyo Lengai: mineralogy of lapilli and mixing of silicate and carbonate magmas. Mineral Mag 56:1–16CrossRefGoogle Scholar
  7. Dawson JB, Pinkerton H, Pyle DM, Nyamweru C (1994) June 1993 eruption of Oldoinyo Lengai, Tanzania: exceptionally viscous and large carbonatite lava flows and evidence for coexisting silicate and carbonate magmas. Geology 22:799–802CrossRefGoogle Scholar
  8. Dawson JB, Keller J, Nyamweru C (1995) Historic and recent eruptive activity of Oldoinyo Lengai. In: Bell K, Keller J (eds) Carbonatite volcanism: Oldoinyo Lengai and the petrogenesis of natrocarbonatites. Springer, Berlin, pp 4–22Google Scholar
  9. Dawson JB, Pyle DM, Pinkerton H (1996) Evolution of natrocarbonatite from a wollastonite nephelinite parent: evidence from the June 1993 eruption of Oldoinyo Lengai, Tanzania. J Geol 104:41–54CrossRefGoogle Scholar
  10. GVN (1994) Oldoinyo Lengai: new active hornito and central depression. Bull Global Volc Network 19(09)Google Scholar
  11. GVN (1999) Oldoinyo Lengai: lava flow spilling over the crater rim in November 1998. Bull Global Volc Network 24(02)Google Scholar
  12. GVN (2002) Oldoinyo Lengai: lava exits crater at 3 points during January 2001–September 2002. Bull Global Volc Network 27(10)Google Scholar
  13. GVN (2003) Oldoinyo Lengai: continuing lava flows and vent activity in late December 2002. Bull Global Volc Network 28(02)Google Scholar
  14. GVN (2004) Oldoinyo Lengai: during February 2004, lavas still escape crater; temperature measurements. Bull Global Volc Network 29(02)Google Scholar
  15. GVN (2005a) Oldoinyo Lengai: tall hornito almost reaches summit elevations; more lava spills over rim. Bull Global Volc Network 30(04)Google Scholar
  16. GVN (2005b) Oldoinyo Lengai: lava continues to spill over crater rim through much of 2005. Bull Global Volc Network 30(10)Google Scholar
  17. GVN (2006) Oldoinyo Lengai: unusual activity at summit crater during late March and early April 2006. Bull Global Volc Network 31(03)Google Scholar
  18. GVN (2007) New lava linked to Plinian eruptions of August-September 2007. Bull Global Volc Network 32(11)Google Scholar
  19. Huppert HE, Sparks RSJ (1985) Komatiites I: eruption and flow. J Petrol 26:694–725Google Scholar
  20. Huppert HE, Sparks RSJ, Turner JS, Arndt NT (1984) Emplacement and cooling of komatiite lavas. Nature 309:19–22CrossRefGoogle Scholar
  21. Ihucha A (2006a) Villagers flee as volcano erupts. The Guardian, Arusha: 04–01–2006Google Scholar
  22. Ihucha A (2006b) Keep off Oldoinyo Lengai, NCAA warns. The Guardian, Arusha: 04–15–2006Google Scholar
  23. Jarvis RA (1995) On the cross-sectional geometry of thermal erosion channels formed by turbulent lava flows. J Geophys Res 100:10,127–10,140CrossRefGoogle Scholar
  24. Kafumu PD, Petro FN, Mulabwa D (2006) Report on the investigation of Oldoinyo Lengai volcanic eruption of 28–29 March 2006. The United Republic of Tanzania ministry of energy and minerals internal report, pp 31Google Scholar
  25. Keller J, Krafft M (1990) Effusive natrocarbonatite activity of Oldoinyo Lengai, June 1988. Bull Volcanol 52:629–645CrossRefGoogle Scholar
  26. Keller J, Zaitsev AN (2006) Calciocarbonatite dykes at Oldoinyo Lengai: the fate of natrocarbonatite. Can Mineral 44:857–876CrossRefGoogle Scholar
  27. Kervyn M, Harris AJL, Belton F, Mbede E, Jacobs P, Ernst GGJ (2008) Thermal remote sensing of the low-intensity thermal anomalies of Oldoinyo Lengai, Tanzania. Int J Remote Sensing (in press)Google Scholar
  28. Klaudius J, Keller J (2006) Peralkaline silicate lavas at Oldoinyo Lengai, Tanzania. Lithos 91:173–190CrossRefGoogle Scholar
  29. Mattsson HB, Hode Vuorinen J (2008) Emplacement, cooling and inflation of lava flows during the March-April 2006 eruption of Oldoinyo Lengai, Tanzania. Bull Volcanol (in press)Google Scholar
  30. Mbede E (2006) Preliminary report on Oldoinyo Lengai March, 24–April, 5, 2006 volcanic eruption. Geology Dept Univ Dar es Salaam Internal Rep, pp 10Google Scholar
  31. McKie D, Frankis EJ (1977) Nyerereite-New volcanic carbonate mineral from Oldoinyo-Lengai Tanzania. Zeitsch Kristallogr 145:73–95CrossRefGoogle Scholar
  32. Mvungi A (2006) Jitters as experts check volcanic action in Ngorongoro. The Guardian, Arusha 04–17–2006Google Scholar
  33. Norton GE, Pinkerton H (1997) Rheological properties of natrocarbonatite lavas from Oldoinyo Lengai, Tanzania. Eur J Mineral 9:351–364Google Scholar
  34. Oppenheimer C (1997) Satellite observation of active carbonatite volcanism at Oldoinyo Lengai, Tanzania. Int J Remote Sen 19:55–64CrossRefGoogle Scholar
  35. Peterson TD (1990) Petrology and genesis of natrocarbonatite. Contrib Mineral Petrol 105:143–155CrossRefGoogle Scholar
  36. Petibon CM, Kjarsgaard BA, Jenner GA, Jackson SE (1998) Phase relationships of a silicate-bearing natrocarbonatite from Oldoinyo Lengai at 20 and 100 MPa. J Petrol 39:2137–2151CrossRefGoogle Scholar
  37. Pinkerton H, Norton GE, Dawson JB, Pyle DM (1995) Field observations and measurements of the physical properties of Oldoinyo Lengai alkali carbonatite lavas, November 1988. In: Bell K, Keller J (eds) Carbonatite volcanism: Oldoinyo Lengai and the petrogenesis of natrocarbonatites. Springer, Berlin, pp 23–36Google Scholar
  38. Pyle DM, Dawson JB, Ivanovitch M (1991) Short-live decay-series disequilibria in the natrocarbonatite lavas of Oldoinyo Lengai, Tanzania: Constraints on the timing of magma genesis. Earth Planet Sci Lett 105:378–396CrossRefGoogle Scholar
  39. Pyle DM, Pinkerton H, Norton GE, Dawson JB (1995) The dynamics of degassing at Oldoinyo Lengai. In: Bell K, Keller J (eds) Carbonatite volcanism: Oldoinyo Lengai and the petrogenesis of natrocarbonatites. Springer, Berlin, pp 37–46Google Scholar
  40. Smithsonian Institution/USGS Weekly Report (2006a) New Activity/Unrest: Oldoinyo Lengai, 29 March–4 April 2006. http://www.volcano.si.edu/reports/usgs/
  41. Smithsonian Institution/USGS Weekly Report (2006b) New Activity/Unrest: Oldoinyo Lengai, 5 April–11 April 2006. http://www.volcano.si.edu/reports/usgs/
  42. Wilmoth RA, Walker GPL (1993) P-type and S-type pahoehoe: A study of vesicle distribution patterns in Hawaiian lava flows. J Volcanol Geotherm Res 55:129–142CrossRefGoogle Scholar
  43. Wright R, Flynn LP, Garbeil H, Harris AJL, Pilger E (2004) MODVOLC: Near-real time thermal monitoring of global volcanism. J Volcanol Geotherm Res 135:29–49CrossRefGoogle Scholar
  44. Zaitsev AN, Keller J (2006) Mineralogical and chemical transformation of Oldoinyo Lengai natrocarbonatites, Tanzania. Lithos 91:191–207CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Matthieu Kervyn
    • 1
  • Gerald G. J. Ernst
    • 1
  • Jurgis Klaudius
    • 2
  • Jörg Keller
    • 2
  • François Kervyn
    • 3
  • Hannes B. Mattsson
    • 4
    • 5
  • Frederic Belton
    • 6
  • Evelyne Mbede
    • 7
  • Patric Jacobs
    • 1
  1. 1.Mercator and Ortelius Research Centre for Eruption Dynamics, Department of Geology and Soil SciencesGhent UniversityGhentBelgium
  2. 2.MGI Mineralogisch-Geochemisches InstitutAlbert Ludwigs-University of FreiburgFreiburgGermany
  3. 3.Royal Museum for Central Africa, Department of Geology–Section of Cartography and Photo-InterpretationTervurenBelgium
  4. 4.Institute for Mineralogy and PetrologySwiss Federal Institute of TechnologyZurichSwitzerland
  5. 5.Nordic Volcanological CenterUniversity of IcelandReykjavikIceland
  6. 6.Middle Tennessee State UniversityMurfreesboroUSA
  7. 7.Department of GeologyUniversity of Dar es Salaam (UDSM)Dar Es SalaamTanzania

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