Where will the lava go?

[TomK]

The question was how magma would return to the summit of Kilauea from the east rift zone, not from underneath Kilauea.

Which could move magma from the East Rift back towards the central magma chamber, and ultimately to the surface itself.

But that's what I was saying in the first place. Sigh...

"I assume what they really mean is that magma underneath the eastern rift zone is returning to a lava chamber well below the summit of Kilauea. I'm having a hard time picturing a fluid going uphill."

And before we go around in circles once again, I've already said I should have said magma chamber rather than lava chamber.

[VancouverIslander]

What happens if or when the lava overflows the crater, where will it go?

South, over Hilina Pali.

To help visualize this see the "Geologic map of the summit region of Kilauea Volcano, Hawaii" by Lockwood and Neal, here:

https://ngmdb.usgs.gov/Prodesc/proddesc_68315.htm

The finer point to note is an eruption, seen in orange in the center bottom (south) side of the caldera, and labeled 9/82, which before it stopped had flowed out of the caldera and began going to the south. There is no pail or caldera wall, or other substantial barrier as there is on all other sides of the summit, in this region. 

This may take a while, in that there is a slight dip of the entire caldera floor towards the north, but all told the south side of the volcano's summit is wide open.

Thank you for posting that information.  I've seen that graphic many times, but without the elevation data.  I'd always wondered about this question since our cottage is near one of the openings to Kazamura Cave and given the location of the Thurston Lava tube.  It concerned me that a summit eruption could one day roll down through Mountain View.  This makes it clear that a summit eruption wouldn't do it.  Something covered that area a few hundred years ago.

[Obie]

What happens if or when the lava overflows the crater, where will it go?

South, over Hilina Pali.

To help visualize this see the "Geologic map of the summit region of Kilauea Volcano, Hawaii" by Lockwood and Neal, here:

https://ngmdb.usgs.gov/Prodesc/proddesc_68315.htm

The finer point to note is an eruption, seen in orange in the center bottom (south) side of the caldera, and labeled 9/82, which before it stopped had flowed out of the caldera and began going to the south. There is no pail or caldera wall, or other substantial barrier as there is on all other sides of the summit, in this region. 

This may take a while, in that there is a slight dip of the entire caldera floor towards the north, but all told the south side of the volcano's summit is wide open.

Thank you for posting that information.  I've seen that graphic many times, but without the elevation data.  I'd always wondered about this question since our cottage is near one of the openings to Kazamura Cave and given the location of the Thurston Lava tube.  It concerned me that a summit eruption could one day roll down through Mountain View.  This makes it clear that a summit eruption wouldn't do it.  Something covered that area a few hundred years ago.

If the caldera gets that full, a rift zone eruption would probably result first. No one is safe !

[MyManao]

If the caldera gets that full, a rift zone eruption would probably result first...

Actually, that might not be the case. You will recall that the entire summit caldera, in its current configuration, is only a couple of hundred years old. Yes, the entire caldera, not just Halemaumau crater.

Think about that. Before 1790 there was not a large, miles in diameter, caldera. And, the mountain was sending lava flows to places we don't consider under the threat of future inundation, like, for instance, Volcano Village and the Volcano Golf Course subdivision. Sheesh the entire park entrance and visitor center area, KMC, are all on very recent flows, 250- 400 years old.

All things considered, I believe there is every reason to think the caldera could fill up, and as I pointed out it would initially spill towards the South as it is filling. But over all, with the way the vents fan flows in all directions over time, and create perches to defy what we would otherwise think should happen, the sky's the limit. 

Of course, we do not have much of a historical perspective. What percentage of the time does the mountain reoccupy its rifts verses build the summit? We don't know. And with Kilauea, which pretty much covers itself every 750 - 1000 years, we can't learn everything from what we see around us.

To see, and appreciate how this is, go back to the summit map I referenced in my last post and study the distribution of flows on the different sides of the caldera. It's an incredibly dynamic mountain. And our's, in a single lifetime, a very limited window into what is really going on here. But, OMG, is it fun to contemplate.

[AaronM]

Any wild chance that it flows towards Pahala?

[Obie]

Pahala is in Mauna Loa's lava zone. It could flow toward Pahala but is blocked from getting to Pahala.

[MyManao]

Pahala is in Mauna Loa's lava zone. It could flow toward Pahala but is blocked from getting to Pahala.

Wow wait a minute. Technically, you are right, Pahala is on Mauna Loa. But in reality? It should be noted, Pahala is very very close to the contact between Mauna Loa and Kilauea, with only a few feet (less than 20 in some instances) of vertical relief that would not prevent flows from Kilauea from inundating the area.

This can most graphically be seen on the Geologic map of the Island of Hawaii, which is here:

https://pubs.er.usgs.gov/publication/i2524A

And on Plate 3 specifically, which encompasses the Southwest side of the island, and is directly accessed here:

https://pubs.usgs.gov/imap/2524a/plate-3.pdf