Thursday, January 21, 2010

Bottomed-out deflation ~ Kilauea GPS observation ~ Pit Vent video

The deformation graphs reveal deflation has leveled out at a very low range (-7 to -9).
As expected, these low magma pressures are manifesting as a lessening of eruptive lava from the Pu`u O`u fissure field and corresponding surface flows of molten lava makai (toward the sea) of there. Reports from those looking mauka (inland) from the Kalapana Gardens area after dark last night confirm a lessoning of surface lava in the areas I photographed and posted yesterday.

The five days of strong inflation of magma that was recorded between January 15 & 20th was strong enough to also be registered on the USGS GPS graphs (scroll down on that site to see it).
The above chart is an interesting record provided by USGS and is their Global Positioning System (GPS) that is graphing the change in distance between two stations located on opposite ides of KÄ«lauea's caldera. A rapid increase in distance can be interpreted as inflation of the summit magma reservoir. This graphs is from today, and note the two up-tics; one in July 2008 and the other right now – both indicate rapid and strong inflation.
July 2008 was when we had some of the most intense lava explosions entering the ocean at Waikupanaha. Below are two images I took from the County viewing area on July 14&17th 2008:

And Static lighting flashing inside the plume July 17th, 2008:

And a zoomed in shot the same night:
I wonder if this pronounced up-tic on the GPS graph indicates what we were watching, until the 20th -- the strong surface flows of lava this week -- was the beginning of a similar episode of extra strong eruption with the potential of the dramatic results we witnessed during July’s 2008 episode. The new surface flows of molten lava came downhill fairly fast and in several areas of the mountain at once. Deflation has ended, for now, the chance to know for sure how those flows would play out.

Video: Shot from a helicopter January 7th & 13th, this Quicktime movie clip, using a thermal camera, shows the entire floor of the Halema`uma`u vent and the spectacular lava movement. USGS:“The first half of the video shows observations on January 7, when a dome fountain on the floor of the vent cavity was feeding a wide, vigorously flowing lava stream towards the north. The second half of the video shows observations on January 13, at which point the lava stream had disappeared and two degassing holes were active.”

Lava activity within the Kilauea Crater pit vent has also lessened; glow from there last night was greatly diminished from previous nights this past week.

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