Alkali carbonatite lavas extruded from Oldoinyo Lengai, Tanzania, in November 1988 are similar in composition to lavas extruded in 1960. Extrusion temperatures are 585 ±10 °C. Apparent viscosities in this temperature range are between 0.3 and 120 Pa{dot operator}s, the highest values coming from very frothy and phenocryst-rich magma. The viscosities and temperatures are the lowest known for terrestrial magmas. © 1990 Geological Society of America.
