Where's the lava gonna flow?

[Kelena]

The lava at the summit has been sinking out of sight for the past few days. The plume is still big and fluffy. In my mind I keep thinking of a kind of pistonning action with the summit and Pu'u O'o being individual pistons. But right now there is a sort of stillness.

[PaulW]

I know where Pu'u O'o is, but where's "the summit"?

[Royall]

quote:

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Originally posted by PaulW

I know where Pu'u O'o is, but where's "the summit"?

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The Helema'uma'u pit lake.


Royall

Hale O Na Mea Pa`ani

[Lin W]

This is probably a terribly ignorant question but, I’m going to ask it anyway. Considering all the major earthquakes occurring recently along the edges of the Pacific plate (Chile, New Zealand, Indonesia, Japan, Alaska, et al), with the Japanese quake alone enough to slow the rotation of the earth, could the plate have shifted sufficiently to affect our hot spot and perhaps alter the eruption patterns of our volcanoes? I have no idea if such a thing is even within the realm of possibility…just wondering.

blessed are the cracked for they let in the light

[Carey]

Movement in the Pacific plate does effect where the STATIONARY hot spot is on the Pacific plate....but we would probably not notice the effect here, as this island is no longer on the hot spot....the new island of Lo`ihi is over the hot spot...all of the magma here is mostly residual...even Maui has had active flows in the 1790's, long after it was even near the hot spot.

Oh, and the true summit of Kilauea is slightly away from the Halemaumau crater rim....

Has anyone noticed the amount of fumes that have been coming from Pu'u O'o crater the last couple of days, and no glow at the Halemaumau crater hole??? wonder what THAT means...

[Midnight Rambler]

quote:

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Originally posted by Carey

Movement in the Pacific plate does effect where the STATIONARY hot spot is on the Pacific plate....but we would probably not notice the effect here, as this island is no longer on the hot spot....the new island of Lo`ihi is over the hot spot...all of the magma here is mostly residual...even Maui has had active flows in the 1790's, long after it was even near the hot spot.

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There are "rejuvenated stage" eruptions that take place after the island moves off the hot spot (Punchbowl was only 4,000 years ago, so it could still happen in downtown Honolulu!), but Kilauea is still over it. You can think of it as a broad plume of hot magma that's burned it's way up close to the surface, and then gets the rest of the way by probing around until it finds a stable channel that then forms a volcano.

Also, ever since Molokai, the hot spot has been divided into two separate lines, on the east and west side. Most of the ones on the west have been smaller; Mauna Loa is the first one to get really big. Loihi is the successor to Mauna Loa, but while it's approching its maximum, Mauna Loa still has access to the hot spot. Kilauea still has a long way to go before it maxes out.

quote:

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Oh, and the true summit of Kilauea is slightly away from the Halemaumau crater rim....

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It's just about on the rim, just north of Jaggar Museum.

[missydog1]

I ran across what I think is a fascinating lecture on Kilauea's eruptive cycles. It's a lecture from a geology 205, a course given at UHH. Lots of diagrams too.

I had never heard of "cow patty" lava bombs before.

http://hilo.hawaii.edu/~kenhon/GEOL205/k...efault.htm

This lecture may be familiar to students of the volcano like Carey, csgray, dakine, and all you others, but for me it had some new history and observations beyond what I have read in the USGS histories.

It talks quite a bit about correlations between east rift zone eruptions and dropping of the summit lava lake. I am curious what take others have on what it says.

There is also discussion of how little rift zone activity had occurred in the current century at the time the Puna subdivisions were created.

Good stuff on the 1955 eruption as well, and how that magma may have been stored ever since the 1923 events, over 30 years.