Normally I don't post over the weekend, but volcanoes are on no man's schedule!
After the collapses at Pu`u O`o (see below) and the draining of the lava lake at Halema`uma`u (timelapse video, courtesy of Eruptions reader Pgen Pgen) yesterday afternoon, it appears we have a new vent system opening on Kilauea. According to news from the Big Island, a new fissure has opened between Pu`u O`o and Napau Crater on the east rift zone - it appears to have started ~2-3 hours after the initial collapse at Pu`u O`o. This fits a pattern seen at Kilauea before, most recently in 1997 when Episode 54 produced an up-rift eruption (closer to the summit) after rapid draining/deflation at Pu`u O`o and Halema`uma`u. This event is interpreted as a new intrusion of magma that then mixed with older magma that drained from the summit rift system, and this conclusion is borne out in the chemistry and mineralogy of the lava erupted at the Napau Crater area during this event (in fact, my petrology students look at samples from this event in lab and try to figure out what happened). I wouldn't be surprised if the events this weekend are a similar injection - we saw some of the telltale signs: inflation of the volcanic edifice, high stands at the lava lake, abundant activity at Pu`u O`o. All of these pointed towards new magma entering the system and this fissure is the manifestation of that intrusion.
Steam and gases pouring from the Pu`u O`o vent after the floor in the crater collapsed on March 5, 2011. Image courtesy of HVO/USGS.
Hawaii 24/7 has some great images and video of the new fissure (see below). The fissure appears to be continuing to propagate as some of the images show - the ground is visibly cracked ahead/behind of the fissure and en echelon fissures are steaming as well. The lava itself is producing a 15-20 meter spatter fountains and small lava flows issuing from the fissure. It is clear in the pictures that this new fissure - located SW of Pu`u O`o - is in an area that hasn't seen eruptive activity in quite some time as there are stands of trees and the ground surface is covered in a thin vegetated soil. Big Island News also has some video of the fissure released by HVO, much of it taken within minutes of the fissure opening, all in all very remarkable footage.
The new fissure that opened on March 5, 2011 between Pu`u O`o and Napau Crater on Kilauea. Image courtesy of Hawaii 24/7.
Be sure to keep an eye on all the Kilauea webcams to see if anything changes (however, there is no webcam for the new activity). You can also check the HVO Kilauea Status page for more updates. Feel free to post any/all updates you find on these new developments in Hawai`i.
UPDATE: Here is some more information on the new fissures, updated since this morning.
Top left: Lava issuing from the new fissure. You can see the spatter in the air above the fissure, suggesting a gas-rich lava erupting. The surface cracking in which the eruption is propagating is obvious as well. See the original image here.