[1][2] There are only a small number of glaciers in the Genaldon River's basin, the largest being Maili at approximately 6.8 km2 (2.6 sq mi) in area.

Loud crackling was heard in the nearby settlements and, at times, the Genaldon river was turned into a stream of black mud.

A pulp of ice, water and morainal material then formed a mudflow which streamed down the river's course, stopping near the Tmenikau aul high on the valley slope.

A second mudflow surge occurred on July 6 when a 9 km stretch of the valley floor was buried underneath a mass of ice and rocks.

Ice within the debris began to melt almost immediately, creating new lakes and flooding some settlements which, contrary to the old traditions, had been built on the valley floor.

The surge resulted in the complete destruction of the glacier leaving behind an empty cirque, a phenomenon not previously observed anywhere else.

[3] The large amount of subglacial water resulted in a surge so powerful, that the glacier was practically ejected from its basin.