Effusive natrocarbonatite activity of Oldoinyo Lengai, June 1988

  title={Effusive natrocarbonatite activity of Oldoinyo Lengai, June 1988},
  author={J{\"o}rg Keller and Maurice Krafft},
  journal={Bulletin of Volcanology},
Oldoinyo Lengai in the Tanzanian rift valley is the only active carbonatite volcano in the world and its natrocarbonatitic lavas are unique in composition. The characteristics of effusive natrocarbonatite activity in June 1988 were studied and fresh samples were directly collected from active carbonatitic lava lakes and flows. Analyses of these samples provide the first information on natrocarbonatites since these unusual volcanic rock type was first described from the 1960–1961 eruptions. The… 
Geochemistry and petrogenetic significance of natrocarbonatites at Oldoinyo Lengai, Tanzania: Composition of lavas from 1988 to 2007
Abstract The natrocarbonatites of Oldoinyo Lengai, Tanzania, are unique in magmatic petrology. The historical activity of Oldoinyo Lengai has seen changes from nephelinitic to natrocarbonatitic
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Differentiation of natrocarbonatite magma at Oldoinyo Lengai volcano, Tanzania
Abstract Natrocarbonatite magma, erupted as lava flows in the Tanzanian volcano Oldoinyo Lengai in June and November of 1988, has evolved chemically since its formation. The June and November flows
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Lapilli and unusually thick, high viscosity lavas extruded from Oldoinyo Lengai in June, 1993 are composed of crystal-rich natrocarbonatite containing a small proportion of porphyritic silicate
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Abstract Oldoinyo Lengai, located in the Gregory Rift in Tanzania, is a world-famous volcano owing to its uniqueness in producing natrocarbonatite melts and because of its extremely high CO2 flux.
Nyerereite from calcite carbonatite at the Kerimasi Volcano, Northern Tanzania
The extinct Quaternary Kerimasi volcano located in the southern part of the Gregory Rift, northern Tanzania, contains both intrusive and extrusive calciocarbonatites. One carbonate mineral with a


Altered former alkalic carbonatite lava from Oldoinyo Lengai, Tanzania: Inferences for calcite carbonatite lavas
The active volcano Oldoinyo Lengai, Tanzania, is well known for its extrusions of alkalic carbonatite lava, first witnessed in 1960. An older carbonatite flow from the volcano was originally also
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The petrogenesis of carbonatites has important implications for mantle processes and for the magmatic evolution of mantle melts rich in carbon dioxide, and unusually low magmatic temperatures were confirmed with 1-atmosphere melting experiments on natural samples.
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