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Sure. The constant settling of this island, and all volcanic islands, generate earthquakes.
But odds are more in favor of liquid earth creating them beneath the Kilauea Caldera. No one really knows the actual size & depth of our local magma chambers, but an earthquake nine miles down is not far when magma reservoirs and their conduits run deep into the earths crust. Most earthquakes under Kilauea volcano are associated with magma movement within the vast reservoirs themselves: from deeper supply conduits, collapse of magma chambers (creating caldera’s), or from movement of magma through the rift zone branching out from them. Magma forces deep earth cracks to push apart and or fracture more brittle surrounding rock at any depth below, alongside or above the pressurized magma. When the chambers and their associated conduits become more pressurized, as they have been for the last few days under Kilauea, then this will often generate both shallow and deeper tremblers.
You seem very interested in volcanic geology, you might like this simplified explanation the USGS offers: http://pubs.usgs.gov/gip/hazards/earthquakes.html
And also this page explaining the basics of how the tiltmeters are recording magma movement: http://hvo.wr.usgs.gov/howwork/subsidenc...flate.html
~~ Leigh
quote:
Originally posted by dakine
quote:
Originally posted by PunaLeigh
@ Dakine:
A high or rising rate and volume of magma pressure being pushed up within the magma chambers, as we are seeing now, deforms the surrounding earth and literally bends & cracks it; creating numerous earthquakes....
wow! interesting indeed! but might there be another reason? considering that earthquake was almost nine miles below the surface could there possibly be a different set of forces involved?
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quote:
Originally posted by PunaLeigh
No one really knows the actual size & depth of our local magma chambers...
actually I think a lot more is known than you might be aware of. I was asking my initial question (how was the earthquake at the base of the volcano related to the shallow deformation we are witnessing at the summit's surface) because, when one considers the model of the summit's magma plumbing system, as described by Peter Cervelli and Asta Miklius in "The shallow magmatic system of Kilauea Volcano" the abstract of which can be found at:
http://adsabs.harvard.edu/abs/2002AGUFM.V71A1251C
and begins as follows:
"Geodetic leveling and Global Positioning System (GPS) measurements image a deflating magma reservoir in the southern part of Kilauea caldera. This reservoir, centered about 3.5 km below ground level, has been slowly deflating (~ 2.5 x 106 km3 per year) since the beginning of the Pu`u `O`o eruption. Electronic borehole tiltmeters reveal a secondary, much shallower magma chamber located just east of Halemaumau Crater at about 750 m below ground level. This secondary reservoir produces episodic deformation events, many of which share striking similarities that suggest a corresponding similarity of process...."
it is hard to see as direct a correlation as you imply. though I love your enthusiasm.. it's great!
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@ Dakine:
I had a feeling you were just leading me on with all of this... But in fact I am well versed on the subject and even the Harvard boyz are speculating -- no one knows exactly the dimensions of our magma chambers and are also still making educated guesses based on ongoing research here and elsewhere. I do not appreciate you playing with me on the subject. Feel free to write your own blog on the subject sighting all you sources.
I provide a free source of local information and utilize local geological studies as needed. You can attempt to answer your own challenge as to why a tremor at nine miles deep under an active volcano is NOT related to magma pressures, but do so for your own learning curve. My inference to the relationship is a logical.
quote] Originally posted by dakine
quote:
Originally posted by PunaLeigh
No one really knows the actual size & depth of our local magma chambers...
actually I think a lot more is known than you might be aware of. I was asking my initial question (how was the earthquake at the base of the volcano related to the shallow deformation we are witnessing at the summit's surface) because, when one considers the model of the summit's magma plumbing system, as described by Peter Cervelli and Asta Miklius in "The shallow magmatic system of Kilauea Volcano" the abstract of which can be found at:
http://adsabs.harvard.edu/abs/2002AGUFM.V71A1251C
and begins as follows:
"Geodetic leveling and Global Positioning System (GPS) measurements image a deflating magma reservoir in the southern part of Kilauea caldera. This reservoir, centered about 3.5 km below ground level, has been slowly deflating (~ 2.5 x 106 km3 per year) since the beginning of the Pu`u `O`o eruption. Electronic borehole tiltmeters reveal a secondary, much shallower magma chamber located just east of Halemaumau Crater at about 750 m below ground level. This secondary reservoir produces episodic deformation events, many of which share striking similarities that suggest a corresponding similarity of process...."
it is hard to see as direct a correlation as you imply. though I love your enthusiasm.. it's great!
[/quote]
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Thank you for the explanation, Leigh. I have been wondering about the relationship between the summit and Pu'u O'o. Today the tiltmeter for Pu'u O'o went up (inflation) pretty dramatically while the tiltmeter at the summit remained fairly stable (but elevated over previous periods). Is there a sort of pistoning that goes on between the two vents --when one is inflated, the other is deflated?
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quote:
Originally posted by PunaLeigh
...even the Harvard boyz are speculating...
Just a small correction Leigh. At the time of that paper's writing both Peter and Asta were on HVO's staff (the Harvard link only comes to play in that it is one of the places I found that had the abstract online).
And, as I said.. I love your enthusiasm.. it's great!
btw.. that paper.. "The shallow magmatic system of Kilauea Volcano" was published as part of a USGS book titled "The Puu Oo - Kupaianaha Eruption of Kilauea Volcano, Hawaii: The First 20 Years" and is highly recommended reading for anyone with a serious interest in Kilauea.
from what I know of dakine's background, he has years or decades of experience in the Park and in studying Kilauea. PunaLeigh, you are clearly intelligent and into the same subject. It would be nice to see you guys working together to edify us. Hopefully, no more prickliness is needed ...
I was enjoying the learning opportunity reading both of you until a little friction erupted.
Last two times I went to Jaggar it was a total fizzle and it's a bit of a trip for me. If anyone cares to share in advance when conditions look good up there, I would love it. It's disappointing to drive an hour each way only to hit fog, drizzle, and no glow.
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Kathy, just check the halemaumau webcam before you go:
http://volcanoes.usgs.gov/hvo/cams/KIcam/
It was really glowing a minute ago, & now is dimming.
Dory
That's an idea, Dory ... although I would only start out in the daylight. I guess I can see the weather on the webcam, huh? Last time it was gorgeous weather in Hilo and I got to Volcano and it was raining, nothing to see.
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Since Leigh would not share this himself, here is his very informative blog:
http://hawaiianlavadaily.blogspot.com/
Kathy I would expect that this might help in deciding about a trip up, along with a look at the live cam. I think it is great stuff! I am nominating him for the FBI Blogs right now!
Aloha au i Hawai`i,
devany
www.myhawaiianhome.blogspot.com
www.eastbaypotters.blogspot.com
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Kathy,
This is based on my limited, but extraordinary experience. I went to the plume only twice, and each time was quite dramatic. The second time made it onto my top 20 most extraordinary experiences of my life, and the top 10 of those I can mention.
Viewing tips:
1. Check the music calendar and see if something ELSE is taking place on the volcano in the evening at Kilauea Music Camp (John Keawe played there, for example, in early December).
2. Find someone special and get tickets to the event.
3. Before the event, go outside. Are the trade winds blowing? Good. You must have tradewinds to see the plume. At the moment, the plume is a mess, that is filling the caldera and not going away from the camera. It must be going away from the camera.
4. Before you go to the event, check the overlook vent webcam. See any ripples in the image? Good. That's the lava welling up in the vent within the vent within the caldera.
5. Pack a flashlight and a light jacket.
6. Go to the musical or cultural event, which should end around 10:00 or so.
7. Check the sky. Clear? If not, go home.
8. If the sky is clear and you can see stars, slowly make your way over to the Jagger Museum overlook.
9. Walk down path to overlook using flashlight.
10. Here, luck is required. The plume is not always illuminated. However, even when not illuminated, the plume is impressive on a starry night, and there are few better places to see the stars without eskimo clothing than from the Kilauea caldera.
I didn't do any of this when I had my most memorable plume experience. I was coming back from Kona the southern route late at night. My friend was asleep in the car. I drove to Jagger just a few minutes before midnight. Sky was very, very clear and it was a little warm. Woke her up, we walked down the path using the light from our cell phones. Plume was very white against the dark sky. We watched it for a few minutes and gazed at the stars. Then it noisily exploded with a light that completely filled the caldera and surrounding area. It then glowed a bright red. It was thrilling. Hard to recreate and I probably won't try.
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