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Fundamental changes in the activity of the natrocarbonatite volcano Oldoinyo Lengai, Tanzania

I. New magma composition during the 2007–2008 explosive eruptions

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Abstract

With a paroxysmal ash eruption on 4 September 2007 and the highly explosive activity continuing in 2008, Oldoinyo Lengai (OL) has dramatically changed its behavior, crater morphology, and magma composition after 25 years of quiet extrusion of fluid natrocarbonatite lava. This explosive activity resembles the explosive phases of 1917, 1940–1941, and 1966–1967, which were characterized by mixed ashes with dominantly nephelinitic and natrocarbonatitic components. Ash and lapilli from the 2007–2008 explosive phase were collected on the slopes of OL as well as on the active cinder cone, which now occupies the entire north crater having buried completely all earlier natrocarbonatite features. The lapilli and ash samples comprise nepheline, wollastonite, combeite, Na-åkermanite, Ti-andradite, resorbed pyroxene and Fe–Ti oxides, and a Na–Ca carbonate phase with high but varying phosphorus contents which is similar, but not identical, to the common gregoryite phenocrysts in natrocarbonatite. Lapilli from the active cone best characterize the erupted material as carbonated combeite–wollastonite–melilite nephelinite. The juvenile components represent a fundamentally new magma composition for OL, containing 25–30 wt.% SiO2, with 7–11 wt.% CO2, high alkalies (Na2O 15–19%, K2O 4–5%), and trace-element signatures reminiscent of natrocarbonatite enrichments. These data define an intermediate composition between natrocarbonatite and nephelinite, with about one third natrocarbonatite and two thirds nephelinite component. The data are consistent with a model in which the carbonated silicate magma has evolved from the common combeite–wollastonite nephelinite (CWN) of OL by enrichment of CO2 and alkalies and is close to the liquid immiscible separation of natrocarbonatite from carbonated nephelinite. Material ejected in April/May 2008 indicates reversion to a more common CWN composition.

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References

  • Barns TA (1921) The highlands of the Great Craters, Tanganyika Territory. Geogr J 58:401–416

    Article  Google Scholar 

  • Bell K, Dawson JB (1995) Nd and Sr isotope systematics of the active carbonatite volcano, Oldoinyo Lengai. In: Bell K, Keller J (eds) Carbonatite volcanism: Oldoinyo Lengai and the petrogenesis of natrocarbonatites. IAVCEI Proc Volcanol 4. Springer, Berlin, pp 113–123

    Google Scholar 

  • Bell K, Keller J (eds) (1995) Carbonatite volcanism: Oldoinyo Lengai and the petrogenesis of natrocarbonatites. IAVCEI Proceedings in Volcanology 4. Springer, Berlin, 210 pp

  • Bell K, Simonetti A (1996) Carbonatite magmatism and plume activity: implication from the Nd, Pb and Sr isotope systematics of Oldoinyo Lengai. J Petrol 37:1321–1339

    Article  Google Scholar 

  • Belton F (2007, 2008, 2009) Oldoinyo Lengai: the mountain of God. http://www.mtsu.edu/∼fbelton/lengai.html

  • Church AA, Jones AP (1995) Silicate–carbonate immiscibility at Oldoinyo Lengai. J Petrol 36:869–889

    Google Scholar 

  • Dawson JB (1962) The geology of Oldoinyo Lengai. Bull Volcanol 24:348–387

    Article  Google Scholar 

  • Dawson JB (1998) Peralkaline nephelinite–natrocarbonatite relationships at Oldoinyo Lengai, Tanzania. J Petrol 39:2077–2094

    Article  Google Scholar 

  • Dawson JB (2008) The Gregory Rift Valley and Neogene—recent volcanoes of Northern Tanzania. Geol Soc London Mem 33:1–102

    Article  Google Scholar 

  • Dawson JB, Bowden P, Clark GC (1968) Activity of the carbonatite volcano Oldoinyo Lengai, 1966. Geol Rundsch 57:865–879

    Article  Google Scholar 

  • Dawson JB, Smith JV, Jones AP (1985) A comparative study of bulk rock and mineral chemistry of olivine melilitites and associated rocks from East and South Africa. Neues Jahrbuch für Mineralogie, Abhandlungen 152:143–175

    Google Scholar 

  • Dawson JB, Garson MS, Roberts B (1987) Altered former alkalic carbonatite lava from Oldoinyo Lengai, Tanzania: inferences for calcite carbonatite lavas. Geology 15:765–768

    Article  Google Scholar 

  • Dawson JB, Smith JV, Steele IM (1989) Combeite (Na2.33Ca1.74others0.12)Si3O9 from Oldoinyo Lengai, Tanzania. J Geol 97:365–372

    Article  Google Scholar 

  • Dawson JB, Pinkerton H, Norton GE, Pyle D (1990) Physicochemical properties of alkali carbonatite lavas: data from the 1988 eruption of Oldoinyo Lengai, Tanzania. Geology 18:260–263

    Article  Google Scholar 

  • 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 56:1–16

    Article  Google Scholar 

  • 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 22:799–802

    Article  Google Scholar 

  • 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. IAVCEI Proc Volcanol 4. Springer, Berlin, pp 4–22

    Google Scholar 

  • Donaldson CH, Dawson JB, Kanaris-Sotiriou R, Batchelor RA, Walsh JN (1987) The silicate lavas of Oldoinyo Lengai, Tanzania. Neues Jahrbuch für Mineralogie, Abhandlungen 156:247–279

    Google Scholar 

  • Fischer GA (1885) Bericht über die im Auftrage der Geographischen Gesellschaft in Hamburg unternommene Reise in das Masai-Land 1882–1883. II: Begleitworte zur Original-Routenkarte. Mitt Geogr Ges Hamburg 1885:189–237

    Google Scholar 

  • Freestone IC, Hamilton DL (1980) The role of liquid immiscibility in the genesis of carbonatites—an experimental study. Contrib Mineral Petrol 73:105–117

    Article  Google Scholar 

  • Global Volcanism Network Bulletin (2007) Oldoinyo Lengai (Tanzania). GVN 32, no. 11, 10–16

  • Global Volcanism Network Bulletin (2008) Oldoinyo Lengai (Tanzania), GVN 33, no. 2, 2–6 (J Keller et al.), GVN 33, no. 8, 12–14

  • Global Volcanism Network Bulletin (2009) Oldoinyo Lengai (Tanzania), GVN 34, no. 8, 9–12

  • Guest NJ (1956) The volcanic activity of Oldoinyo L'Engai, 1954. Rec Geol Surv Tanganyika 4:56–59

    Google Scholar 

  • Hamilton DL, Bedson P, Esson J (1989) The behaviour of trace elements in the evolution of carbonatites. In: Bell K (ed) Carbonatites—genesis and evolution. Unwin Hyman, London, pp 405–427

    Google Scholar 

  • Hay RL (1983) Natrocarbonatite tephra of Kerimasi volcano, Tanzania. Geology 11:599–602

    Article  Google Scholar 

  • Hobley CW (1918) A volcanic eruption in East Africa. J East Africa Uganda Nat Hist Soc 13:339–343

    Google Scholar 

  • Keller J, Krafft M (1990) Effusive natrocarbonatite activity of Oldoinyo Lengai, June 1988. Bull Volcanol 52:629–645

    Article  Google Scholar 

  • Keller J, Spettel B (1995) Trace element composition and petrogenesis of natrocarbonatites. In: Bell K, Keller J (eds) Carbonatite volcanism: Oldoinyo Lengai and the petrogenesis of natrocarbonatites. IAVCEI Proc Volcanol 4. Springer, Berlin, pp 70–86

    Google Scholar 

  • Keller J, Zaitsev AN (2006) Calciocarbonatitic dykes at Oldoinyo Lengai, Tanzania: the fate of natrocarbonatite. Can Mineral 44:857–876

    Article  Google Scholar 

  • Keller J, Zaitsev AN, Wiedenmann D (2006) Primary magmas at Oldoinyo Lengai: the role of olivine melilitites. Lithos 91:150–172

    Article  Google Scholar 

  • Keller J, Zaitsev AN, Klaudius J (2007) Geochemistry and petrogenetic significance of natrocarbonatites at Oldoinyo Lengai, Tanzania: composition of lavas from 1988 to 2007. Goldschmidt Conference 2007, Cologne, Abstracts

  • Kervyn M, Klaudius J, Keller J, Kervyn F, Mattsson H, Belton F, Mbede E, Jacobs P, Ernst GGJ (2008a) Voluminous lava floods at Oldoinyo Lengai in 2006: chronology of events and insights into the shallow magmatic system. Bull Volcanol 70:1069–1086

    Article  Google Scholar 

  • Kervyn M, Klaudius J, Keller J, Mbede E, Jacobs P, Ernst GGJ (2008b) Remote sensing study of sector collapses and debris-avalanche deposits at Oldoinyo Lengai and Kerimasi volcanoes, Tanzania. Int J Rem Sens 29:6565–6595

    Article  Google Scholar 

  • Kervyn M, Ernst GGJ, Keller J, Vaughan G, Klaudius J, Pradal E, Belton F, Mattsson H, Mbede E, Jacobs P (2010) Fundamental changes in the activity of the natrocarbonatite volcano Oldoinyo Lengai, Tanzania. II. Eruptive behaviour. Bull Volcanol. doi:10.1007/s00445-010-0360-0

  • Kjarsgaard BA (1998) Phase relations of a carbonated high CaO-nephelinite at 0.2 and 0.5 GPa. J Petrol 39:2061–2077

    Article  Google Scholar 

  • Kjarsgaard BA, Hamilton DL (1989) The genesis of carbonatites by immiscibility. In Bell K (ed) Carbonatites—genesis and evolution. Unwin Hyman, London, pp 388–404

    Google Scholar 

  • Kjarsgaard BA, Hamilton DL, Peterson TD (1995) Peralkaline nephelinite/carbonatite liquid immiscibility: comparison of phase composition in experiments and natural lavas from Oldoinyo Lengai. In: Bell K, Keller J (eds) Carbonatite volcanism: Oldoinyo Lengai and the petrogenesis of natrocarbonatites. IAVCEI Proc Volcanol 4. Springer, Berlin, pp 163–190

    Google Scholar 

  • Klaudius J, Keller J (2004) Quaternary debris avalanche deposits at Oldoinyo Lengai (Tanzania). IAVCEI General Assembly, Pucón, Chile 2004, Abstracts

  • Klaudius J, Keller J (2006) Peralkaline silicate lavas at Oldoinyo Lengai, Tanzania. Lithos 91:173–190

    Article  Google Scholar 

  • Koster van Groos AF, Wyllie PJ (1968) Liquid immiscibility in the join NaAlSi3O8-Na2CO3-H2O and its bearing on the genesis of carbonatites. Am J Sci 266:932–967

    Article  Google Scholar 

  • Macdonald R, Kjarsgaard BA, Skilling IP, Davies GR, Hamilton DL, Black DS (1993) Liquid immiscibility between trachyte and carbonate in ash flow tuffs from Kenya. Contrib Mineral Petrol 114:276–287

    Article  Google Scholar 

  • Mattsson HB, Reusser E (2010) Mineralogical and geochemical characterization of ashes from an early phase of the explosive September 2007 eruption of Oldoinyo Lengai (Tanzania). J Afr Earth Sci (in press)

  • McDonough WF, Sun SS (1995) The composition of the Earth. Chem Geol 120:223–253

    Article  Google Scholar 

  • Mitchell RH (2006) Sylvite and fluorite microcrysts, and fluorite-nyerereite intergrowths from natrocarbonatite, Oldoinyo Lengai, Tanzania. Mineral Mag 70:103–114

    Article  Google Scholar 

  • Mitchell RH (2009) Peralkaline nephelinite–natrocarbonatite immiscibility and carbonatite assimilation at Oldoinyo Lengai, Tanzania. Contrib Mineral Petrol 158:589–598. doi:10.1007/s00410-009-0398-1

    Article  Google Scholar 

  • Mitchell R, Dawson B (2007) The September 24th, 2007 ash eruption of the carbonatite volcano, Oldoinyo Lengai, Tanzania: mineralogy of the ash and implications for the formation of new hybrid magma type. Mineral Mag 71:483–492

    Article  Google Scholar 

  • Neumann O (1894) In: Matschie P, Nachrichten aus den deutschen Schutzgebieten. Deutsch-Ostafrika. Von der wissenschaftlichen Expedition Oskar Neumanns. Deutsches Kolonialblatt 21, pp 421–424

  • Nyamweru C (1990) Observations on changes in the active crater of Oldoinyo Lengai from 1960 to1988. J Afr Earth Sci 11:385–390

    Article  Google Scholar 

  • Nyamweru C (1997) Changes in the crater of Oldoinyo Lengai. J Afr Earth Sci 25:43–53

    Article  Google Scholar 

  • Peterson TD (1989a) Peralkaline nephelinites. I. Comparative petrology of Shombole and Oldoinyo L`engai, East Africa. Contrib Mineral Petrol 101:458–478

    Article  Google Scholar 

  • Peterson TD (1989b) Peralkaline nephelinites. II. Low pressure fractionation and the hypersodic lavas of Oldoinyo Lengai. Contrib Mineral Petrol 102:336–346

    Article  Google Scholar 

  • Peterson TD (1990) Petrology and genesis of natrocarbonatite. Contrib Mineral Petrol 105:143–155

    Article  Google Scholar 

  • Peterson TD, Kjarsgaard BA (1995) What are the parental magmas at Oldoinyo Lengai? In: Bell K, Keller J (eds) Carbonatite volcanism: Oldoinyo Lengai and the petrogenesis of natrocarbonatites IAVCEI Proc Volcanol 4. Springer, Berlin, pp 148–162

    Google Scholar 

  • 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 39:2137–2153

    Article  Google Scholar 

  • Pyle DM, Dawson JB, Ivanovich M (1991) Short-lived decay series disequilibria in the natrocarbonatite lavas of Oldoinyo Lengai, Tanzania: constraints on the timing of magma genesis. Earth Planet Sci Lett 105:378–396

    Article  Google Scholar 

  • Reck H (1914) Oldoinyo L’Engai, ein tätiger Vulkan im Gebiete der Deutsch-Ostafrikanischen Bruchstufe. Branca-Festschrift, Berlin, pp 373–409

    Google Scholar 

  • Reck H, Schulze G (1921) Ein Beitrag zur Kenntnis des Baues und der jüngsten Veränderung des L´Engai Vulkans im nördlichen Deutsch-Ostafrika. Z Vulk 6:47–71

    Google Scholar 

  • Richard JJ (1942) Volcanological observations in East Africa. I Oldoinyo Lengai. The 1940–1 eruption. J East Africa Uganda Nat Hist Soc 16:89–108

    Google Scholar 

  • Simonetti A, Bell K, Shrady C (1997) Trace and rare-earth-element geochemistry of the June 1993 natrocarbonatite lavas, Oldoinyo Lengai (Tanzania). Implications for the origin of carbonatite magmas. J Volcanol Geotherm Res 75:89–106

    Article  Google Scholar 

  • Uhlig C (1905) Bericht über die Expedition der Otto-Winter-Stiftung nach den Umgebungen des Meru. Zeitschrift der Gesellschaft für Erdkunde zu Berlin, Jg 1905, 120–123

  • Uhlig C, Jaeger F (1942) Die Ostafrikanische Bruchstufe und die angrenzenden Gebiete zwischen den Seen Magad und Lawa ya Mweri sowie dem Westfuss des Meru. Deutsches Inst Länderkde, Wissensch Veröffentlichungen, Neue Serie 10, 284 pp

  • Vaughan G, Kervyn M, Realmuto V, Adams M, Hook S (2008) Satellite measurements of recent volcanic activity at Oldoinyo Lengai, Tanzania. J Volcanol Geotherm Res 173:196–206

    Article  Google Scholar 

  • Veksler IV, Petibon C, Jenner GA, Dorfman AM, Dingwell DB (1998) Trace element partitioning in immiscible silicate–carbonate liquid systems: an initial experimental study using a centrifuge autoclave. J Petrol 39:2095–2105

    Article  Google Scholar 

  • Wiedenmann D, Zaitsev AN, Britvin SN, Krivovichev SV, Keller J (2009) Alumoåkermanite, (Ca, Na)2(Al, Mg, Fe2+)(Si2O7), a new mineral from the active carbonatite–nephelinite–phonolite volcano Oldoinyo Lengai, northern Tanzania. Mineral Mag 73:373–384

    Article  Google Scholar 

  • Williams RW, Gill JB, Bruland KW (1986) Ra-Th disequilibria systematics: timescale of carbonatite magma formation at Oldoinyo Lengai volcano, Tanzania. Geochim Cosmochim Acta 50:1249–1259

    Article  Google Scholar 

  • Zaitsev AN, Keller J, Spratt J, Perova EN, Kearsley A (2008a) Nyerereite–pirssonite–calcite–shortite relationships in altered natrocarbonatites, Oldoinyo Lengai, Tanzania. Can Mineral 46:1077–1094

    Article  Google Scholar 

  • Zaitsev AN, Keller J, Spratt J, Jeffries TE, Sharigin VV (2008b) Chemical composition of nyerereite and gregoryite in natrocarbonatites of Oldoinyo Lengai Volcano, Tanzania. Proc Russ Mineral Soc 137:101–111

    Google Scholar 

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Acknowledgments

Access to the summit of Oldoinyo Lengai had become difficult since the paroxysm of 4 September 2007. Tim Leach from Ngare Sero Lodge explored and opened, together with local Maasai, a new route from the east–southeast. The expedition of 7 December 2007 used this route with the help of the Maasai guides Saringe, Tumba, and Lekoko from Engare Sero. This logistic support is gratefully acknowledged. We thank Benoît Wihelmi, Tim Leach, and Tom Pfeiffer for providing and granting permission to use some of their spectacular pictures. Julie Albaric, Evelyne Pradal, and Chris Weber contributed the additional samples of November 2007 and February 2008 ashes and lava bombs of April 2008, respectively. We also thank all who contributed with observations and photographs, which enabled to follow the activity evolution from distance. This includes in particular Thomas Holden, Jens Fissenebert, and Chris Weber. We acknowledge stimulating discussions with Barry Dawson, Roger Mitchell, and Bruce Kjarsgaard. Research of JKe and JKl at OL is supported by DFG project Ke 136/40. MK and GGJE are supported by postdoctoral grants of the Fonds voor Wetenschappelijk Onderzoek-Vlaanderen. Melanie Schrage, Sigrid Hirth-Walther, Isolde Schmidt, and Dagmar Flemming of MGI Freiburg were of invaluable help in sample and thin section preparation and chemical analyses. Hiltrud Müller-Sigmund gave expert advice at the electron microprobe. Jörg Erzinger of GFZ Potsdam is thanked for his spontaneous availability when asked for additional fluorine and chlorine determinations. The paper greatly benefited from the careful, competent, and constructive reviews by Barry Dawson and Bruce Kjarsgaard.

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  1. Jurgis Klaudius

    Present address: Terratec Geophysical Services, Schillerstrasse 3, 79423, Heitersheim, Germany

Authors and Affiliations

  1. Institut für Geowissenscahften, Mineralogie–Geochemie, Albert-Ludwigs-Universität Freiburg, Albertstrasse 23b, 79104, Freiburg, Germany

    Jörg Keller & Jurgis Klaudius

  2. Mercator and Ortelius Research Centre for Eruption Dynamics, Department of Geology and Soil Science, Ghent University, Ghent, Belgium

    Matthieu Kervyn & Gerald G. J. Ernst

  3. Institute of Geochemistry and Petrology, ETH Zürich, Swiss Federal Institute of Technology, Zurich, Switzerland

    Hannes B. Mattsson

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  1. Jörg Keller
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Correspondence to Jörg Keller.

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Keller, J., Klaudius, J., Kervyn, M. et al. Fundamental changes in the activity of the natrocarbonatite volcano Oldoinyo Lengai, Tanzania. Bull Volcanol 72, 893–912 (2010). https://doi.org/10.1007/s00445-010-0371-x

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