Veniaminof Volcano Lava Flows 1/3 Mile into Caldera

Jun 19, 2013

The lava flow from the Veniaminof volcano now extends nearly a third of a mile down the volcanic cone, while ash puffs are reaching up to 15 thousand feet.  The lava flow is about 160 feet wide, stretching about down the cone into its enormous caldera full of glacial ice.  There the super hot lava is melting some snow and ice according to UAF’s Jessica Larsen, the Acting Coordinating Scientist for the Alaska Volcano Observatory.

"This is a really large caldera, there' s a lot of snow and ice in there.  I would suspect that from a lava flow of this size, the amount of meltwater is probably pretty small," said Larsen.

Scientists don’t expect the lava flow to go beyond the base of the cone within the caldera. This is the first time in 20 years that Veni has spewed out lava.  In past eruptions, like 1984 and 1993 there was no sign of increased flow into the Muddy River Valley. 

"It's possible when you have these lava flows that interact with glacial ice or snow, they'll melt the snow or ice and create a lahar, which is an Indonesian word that means mudflow, originating on the flank of a volcano, it's like a muddy flood.  At this point, we don't have any observations of lahars being created, but it's possible that this could create some meltwater which would then create a lahar," said Larsen.

Thanks to pilot reports and an FAA camera 22 miles away in the community of Perryville, scientists estimate that the ashplume Tuesday reached close to 15 thousand feet.

There are no reports of flights impacted by Veiniaminof.  Trace amounts of ash have fallen within the volcano’s caldera.

"The ash plumes that come off of these little punctuated explosions are typically really diffuse, they don't generally don't reach more than 20,000 feet above sea level. The ash fallout from these is typically limited just to the flanks of the volcano.  In terms of the whole spectrum of explosive versus effusive volcanic behavior, this is more on the low level, low explosivity, more effusive side even though we are having these punctuated bursts of and ash emissions and small explosions," said Larsen.

Veniminoff has been rumbling since June 6th.  Lava flow began around last Thursday.  The volcano’s alert level is watch, with an aviation code orange.