The Dynamics of Degassing at Oldoinyo Lengai

This chapter summarizes field observations of degassing made at Oldoinyo Lengai in 1988 and their implications for the dynamics of the Lengai magma system. Observations of bubbles bursting in a lava lake, and sudden changes in magma level and vesicularity at active vents are consistent with the degassing model developed by Jaupart and Vergniolle (1988, 1989), and suggest that the shallow plumbing system comprises several small (<10-m radius) chambers containing transient foam layers which may, in turn, be connected at depth to a single, larger chamber.