Floating Pumice – an Oceanic Hazard?



Under water volcanoes, both shallow and deep, erupt more often than we think. When an exceptionally large underwater volcano erupts, the lava that is produced cools quickly, trapping gas bubbles within the rock. This forms pumice, a highly vesicular, highly porous rock that is light enough to float on water.

Large enough volumes of pumice can be violently ejected during eruptions, rising to the surface of the ocean to form floating rafts of pumice. Such pumice rafts have been seen after historical eruptions such as Krakatoa erupting in 1883, spewing pumice into the ocean and clogging harbors in Indonesia.


The Predicted Volcanic Eruption

Members of the Volcanic Risks Solutions team at Massey University in New Zealand have successfully predicted a volcanic eruption.  

A volcanic eruption of their creation, that is...!

Picture: The Volcanic Risks Solutions team; Shane Cronin,
Eric Breard (top), Dr Gert Lube and Professor Jim Jones with the Tower of Doom.

This team, led by Professor Shane Cronin and Dr Gert Lube, has created the world's first research project to investigate pyroclastic flows.

Pyroclastic flows are flows of a mixture of hot gas and particles that are emitted during a volcanic eruption, particularly like the eruptions found in New Zealand. 

A New Year, A Continuing Eruption


Mount Sinabung, a volcano located on the island of Sumatra, in Indonesia, is still erupting.


sinabung map


As one of the 129 active volcanoes in Indonesia, its current eruption started in September 2013 and has since erupted over several times a day. The initial eruptions of ash and lava have escalated into pyroclastic flows that have stretched kilometers out from the flanks of the volcano.