Thursday, January 23, 2014

WAITING TO INHALE: Recent changes in Kilauea's eruptive activity

After a period of relative stability and quiet, instruments on Kilauea's flanks signaled the beginning of what could mean changes - a big deflation.

Changes in pressure in the magma beneath the summit and Pu'u 'O'o vent cause the ground to rise or fall minute amounts, as if the volcano is breathing. Scientists monitor these changes to try and understand what's going on beneath the surface.

Inflation is caused by magma moving up closer to the surface and deflation occurs when pressure drops and magma recedes or erupts. The significance of these cycles is not yet well understood by science.

This week we saw the very first Deflation/Inflation cycle in over a month begin with a big deflation. The green line on the chart below tracks deflation at Kilauea summit, which dipped dramatically on the 18th. The blue line tracks deflation at Pu'u 'O'o cone. The cone, which is fed by magma from the summit, followed the summit's deflation about 5.5 hours later.
Changes we've seen so far include the collapse of the northeast spatter cone within Pu'u 'O'o crater which has fed the Kahauale'a 2 flow (the island's only active surface lava flow at this time). The spatter cone collapsed, presumably due to reduced pressure. For the last few days it appeared that the cone complex still fed the Kahauale'a 2 flow, however the flow has dramatically weakened.

The lava lake within Halema'uma'u crater at Kilauea summit dropped more than 65 feet in response to the deflation. You can see in this screenshot from the webcam the lake deep within the cavity.


Yesterday, after 4 days totaling more than 5.5 microradians of deflation, a cycle of inflation began at the summit. Scientists from the Hawaiian Volcano Observatory expect an increase in eruptive activity with inflation over the next few days. It will probably occur on the Kahauale'a 2 flow field or somewhere else within or near Pu'u 'O'o crater.

Below is a screenshot of spattering at the margin of the lava lake within Halema'uma'u.


These changes are exciting to us and we're watching closely to see what happens.
Check out our DAILY LAVA ACTIVITY UPDATE to find out what's happening!