Sheveluch Volcano

(Also Shiveluch or in Russian: Шивелуч)

Ash plume from Sheveluch volcano on September 03, 2011. Photo by Yuri Demyanchuk.

Sheveluch at a Glance:

Most Recent Activity (Week of November 4-11, 2011):  Moderate seismic activity was detected at Shiveluch during 4-11 November, and indicated that possible ash plumes rose to a maximum altitude of 4.5 km (14,800 ft) a.s.l. Ground-based observers noted that a viscous lava flow continued to effuse in the crater formed during a 2010 eruption. Strong fumarolic activity at the lava dome was observed during 2-3 and 5-9 November; cloud cover prevented observations on the other days. Satellite imagery showed a daily thermal anomaly over the lava dome and gas-and-steam plumes containing small amounts of ash that drifted 25 km E on 5 November.

What’s it doing right now? WEBCAM

Lots of lovely photos of Shiveluch

Historic large plinian eruptions:

1964  Eruption included a large-scale slope failure, small phreatic explosion and a powerful plinian eruption resulting in pyroclastic fall and flows accompanied by mudflows (lahars).  A 1.5 x 3 km explosion crater was formed during this eruption.

1854 Large eruption with explosivity index of 5

Geologic History: Shiveluch is a massif – a complex pile of overlapping stratocones, domes, lava fields and craters.  It has a history of large flank failures.  Recent Shiveluch activity includes the two large plinian eruptions above, and more than 10 moderate dome-associated events, which produced minor pyroclastic flows and ashfalls. The last eruption of this kind in May 2001 caused 30-km long lahars. Due to its frequent and large explosive eruptions, Shiveluch poses a hazard not only to the nearby towns of Kliuchi and Ust’-Kamchatsk, but also for aviation pathways between the USA and all of the Far East.

Info from KVERT and the Smithsonian Global Volcanism Network.

Have fun!

Stay tuned for next month’s quiz!

Have fun!

Lava channels flowing down eastern flank of Pu`u `O`o, Sept 23, 2011

Flew out to the new fissures today accompanied by Tim Orr of USGS (flown by David Okita of Volcano Helicopters, of course – he set up some great aerial shots for me today – click on photo to see video clips).  We got put down right below the fissures and upwind of the huge channels barreling down the slopes of Pu`u `O`o, and spent a few hours following the flows. Even though it has been days since the fissure broke open, there were still good-sized open channels.  We had to climb up on some pretty hot flows to get a good view.  I was a little worried about the boot soles, but they held up fine.  We did have some cooler ground to retreat to.  The terrain up here is all shelly pahoehoe – hollow rolls of lava that form near vents.  The rock is generally one or two inches thick – and thus collapses easily under your weight – but the hollow spaces you fall into can be a lot deeper than that.  Bad enough if it’s cold, but a real bummer when it’s hot.  I made it without any shin injuries and only got a little stuck once.  Walking in the folds helps because it is a little thicker there, though you end up having to contort your ankles a bit.

Lava channel and fissure on Pu`u `O`o, 9/23/11

Up near the fissure, where the cone is steeper, the lava in the channel was moving fast – it was very impressive.  Closeup shots were hard to get through the intense heat waves, though.  The sound was also very difficult to capture through the wind and buzzing helicopters.  The fissure would make the occasional jetting and hissing noises, while the sound of the channel itself is more of a rustling, whispering sound, interspersed with thumps and clinks and rattles as solid bits of crust scrape against the sides.

Crust tearing from sides of rushing lava channel, 9/23/11

I was reminded as we picked our way along the channel that this job is much easier with two people.  Fortunately Tim offered to carry the tripod, which helped a lot.  You really want a hand free when walking on shelly pahoehoe.  The problem with working on hot ground is that you can’t set anything down, so setting up a tripod and camera, getting a drink of water, taking gloves on and off, changing batteries… it all requires a lot of maneuvering.  You can’t set the backpack down or the nylon might begin to melt.  We were wearing flight suits and heavy boots, of course, so the heat was manageable, except when we got really close to the channel – there the radiant heat was intense. Fortunately David let us leave our helmets and my shooting rig in the chopper.

Lava pouring over falls and splashing into a pool, 9/23/11

The last place we made it to was the most spectacular – a huge lava falls with a pond at the base. We were able to get right up to it and look down into the incised channel.  The lava at the base of the falls was splashing up like a small dome fountain and occasionally spattering lava on the walls.  The amount of lava seemed to wax and wane a bit.  We’d noticed along the channel above how the crust would build along the sides and then break away as the lava level rose.  Not sure how much is local effects (constriction of the channel forcing the level to rise) or an actual change in effusion rate of the lava.  But by the time the lava reached the falls it would increase and decrease noticeably.  And wow, the falls were impressive.   Altogether a great filming day.

Stay tuned for next month’s Kilauea Quiz…