May 9-10: USGS Warns of Possible Steam Explosions

Attention shifted back to the summit on May 9, when a 3.1 earthquake set off a rockfall that agitated the lava lake and sent up a 6000-foot poof of ash (video clip National Parks site):

Rockfall into Halema’uma’u lava lake sends up plume of ash, 8:27 May 9.

Rockfalls caused poofs of ash like this even back when the lava lake was full, but that was more than usual. (See also USGS video from May 7, when lava lake was still visible, showing how falling rocks agitate it).

However, that was just a teaser. The big news was the dropping lava lake…

…prompted HVO to issue its first warning about steam explosions if the lava dropped below the water table.

Hawaii Volcanoes National Park closed Friday May 11 as a precaution, since the lava lake was projected to reach the water table sometime that day. For the next few days it continued to send up a white plume of steam and/or ash clouds when rocks from the sides of the chimney fell in:

[USGS] May 11, 9:12 AM: second ash explosion
On steam (phreatic) explosions:

Continue reading May 9-10: USGS Warns of Possible Steam Explosions

Apr 30: Pu’u O’o Crater Collapse

The floor of Pu’u O’o collapsed in stages starting at 2PM in the afternoon and evening of April 30. Poor weather, fog and clouds obscured the view, but the thermal webcam positioned on Pu’u O’o’s  north rim captured it. Timelapse April 28-May 1:

This isn’t the first time it’s collapsed. Here’s a regular webcam timelapse movie of Pu’u O’o’s crater floor collapsing on March 5, 2011.

So there’s a chance the lava may return.