There have been five historical eruptions at the volcano's relatively southwestern rift zone, and 24 along its more active eastern rift zone, mostly along its upper section.
Rift flank uplift occurs when the crust on the side of a rift zone converges with a stronger crust, usually resulting in crustal thickening and a subduction zone.
Slow spreading results in a strong and thick axial elastic plate, and slower volcanic extrusions from the rift zone, resulting in high topography when merged with plume-related volcanism.
