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dgavin
2010-Feb-06, 07:28 PM
Crater Lake (Mt. Mazama) had a small micro swarm of earthquakes this week lasting about 8 hours. These were very weak quakes, < 0.1 in magnitude, and nothing to be concerned about. It's considered normal background activity for volcanic regions.

However in 7 years of watching the webicorders for volcanoes, this is the first event like this I have noted at Crater Lake, so posting about it.

Also attaching the webicorder images for a permanent record here.

hhEb09'1
2010-Feb-06, 07:48 PM
Those little blue (and red) squiggles?

Squink
2010-Feb-06, 11:55 PM
Those little blue (and red) squiggles?Yup. Looks like Llao may finally be emerging from his time in the Below-World.
(http://oregonexplorer.info/craterlake/history.html)

dgavin
2010-Feb-07, 02:33 AM
Yup. Looks like Llao may finally be emerging from his time in the Below-World.
(http://oregonexplorer.info/craterlake/history.html)

I wouldn't go that far yet.

This is such weak activity that it is likely only a deep achient and empty lava tube collapsing. Still fairly cool to see when usualy you only see avelanches and rock falls on the siesmographs for Crater Lake.

EricFD
2010-Feb-07, 03:05 AM
It's fun to catch the first activity like this after seven years. Thanks for the webicorder thumbnails.

Eric

dgavin
2010-Feb-11, 08:25 PM
The webicorders been down for a few days, got a change too look back at them and it appears...

That there might have been a harmonic tremor around the Crater Lake region on the 8th, about 9am, and lasting for around 20 minutes. This was also picked up at Roseburg siesmographs as well as a few others.

I still think this isn't anything to be concerned about. But with Yellowstone quieting down, it's definantly got my intrest piqued.

dgavin
2010-Feb-12, 03:22 PM
Wow, and another harmonic tremor at around 3pm yesterday lasting a bit over an hour. I am not certain these at located at crater lake exactly. As they are also picked up at Shata's stations, Roseberg Stations, and the stongest signal at Grantspass station.

All on slow period siesmographs. Definately not a man made signal as it's too wide spread, and I don;t think it's wind. It's too consitant on the stations it shows up on, to be wind.

dgavin
2010-Feb-12, 08:03 PM
I Just got word that there /was/ a EQ swarm at the MT. Lassen area on the 10th, however that only might cover the siesmograph readings I saw on the same day, but not yesterdays longer event.

May or may not be related events.

dgavin
2010-Feb-24, 08:51 PM
Nothing new here since.

I'm still fairly certain that the swarm was more likely from a lava tube collapse. It has some distinct oodities to it that are vaugly similar to those of a sink-hole collapse on seismographs.

The other events looking like tremors, actualy were, but i've nailed down the location best as I could of those (minus the Mt Lassen events), as to being somewhere around Mt. McGloughlin (about half way between crater lake and grants pass). It's about as accurate as I can get without direct access to the seismograph datasets.

So they are unrelated events to the swarm at Crater Lake.

BigDon
2010-Feb-24, 11:40 PM
Yup. Looks like Llao may finally be emerging from his time in the Below-World.
(http://oregonexplorer.info/craterlake/history.html)

Still, it's better than the Great Horror trapped under there in the Shadow Run millieu. Which was the first thing I thought.

Great Horrors are uniquely bad news as no two are the same. And they didn't get that name by cheating at tiddlywinks.

And collapsing lava tubes are a very bad sign in this instance. It means what occupied them does so no longer.

I shall pay close attention to further developments.

dgavin
2012-Feb-28, 07:55 PM
USGS has produced a new way to list volcanos (instead of acvtive/inactive/dormant) based on threat assement. Very High Risk, High Risk, Moderate Risk, Low Risk, Negligable Risk.

Taking the number 1 Very High Risk postion in Oregon, is Crater Lake.

-What?- Was my main reaction to this, but I've read up on papers behind this new rating scheme and can summerize why, in order of thier value to risk from highest to lowest.


Lack of Adaquate Monitoring
Indications of Thermal Heating at bottom of Crater Lake (crater lakes bottom is 3-6C warmer then water 100 feet above bottom)
Potential of Lake's release of Supersaturated CO2, with potential of additonal Methanehydrates, and other gasses inundated into the water at depth.
Potential of Lake Wall Weakening (collapsing) and Massive Flood
Potential for Eruptions
Potential for super explosive Hydromagmatic Eruptions (Megaton range if magma intrusion into lake occures at same time as lake wall collapse)

korjik
2012-Feb-29, 09:29 AM
Sounds more like USGS has produced a new way to get a bigger budget.

If the monitoring stations are detecting earthquakes at a small fraction of a point in magnitude, then is seems to me that the rest is mostly covered.

jlhredshift
2012-Feb-29, 02:01 PM
I am curious to know if anyone knows of a confirmed exposure of a collapsed magma tube that was at one time at a great depth?

Swift
2012-Feb-29, 04:26 PM
Sounds more like USGS has produced a new way to get a bigger budget.
BAUT has no geology exception to the no-politics rule. Let's not take the conversation in that direction. Thanks,

dgavin
2012-Feb-29, 08:29 PM
Sounds more like USGS has produced a new way to get a bigger budget.

If the monitoring stations are detecting earthquakes at a small fraction of a point in magnitude, then is seems to me that the rest is mostly covered.

Actualy from what I gathered out of the papers, the most prevelent danger (and most likely) at Crater Lake is a disruption of the lake water by an avalanche, landslide or quake, that causes a explosive release of all the supersaturaed CO2 at depth. The papers did not give an amount of estimated CO2, but it did mention that a complete release of all CO2 would cause massive fatalities in the Klamath Basin, with elevated CO2 consentrations reaching as far as Bend and parts of northern california.

That inidcates to me that the CO2 buildup in Crater Lake, is complete Orders of Magnitude greater than the one in africa that released a lethal dosage some years ago.

*edit, spelling and to add*

This sort of event would likely have no seismic forwarning to it, or very minimal seismic warnings.

korjik
2012-Mar-01, 05:40 AM
Actualy from what I gathered out of the papers, the most prevelent danger (and most likely) at Crater Lake is a disruption of the lake water by an avalanche, landslide or quake, that causes a explosive release of all the supersaturaed CO2 at depth. The papers did not give an amount of estimated CO2, but it did mention that a complete release of all CO2 would cause massive fatalities in the Klamath Basin, with elevated CO2 consentrations reaching as far as Bend and parts of northern california.

That inidcates to me that the CO2 buildup in Crater Lake, is complete Orders of Magnitude greater than the one in africa that released a lethal dosage some years ago.

*edit, spelling and to add*

This sort of event would likely have no seismic forwarning to it, or very minimal seismic warnings.

If that was a likely threat, showing it would not be all that hard. Fixing it would not be all that hard either.

dgavin
2012-Mar-01, 09:31 PM
If that was a likely threat, showing it would not be all that hard. Fixing it would not be all that hard either.

Showing it in real time is not hard, no, giving adaquate warning that such an event might happen, is near impossible, again as there is no precursor activity.

Fixing it is a lot harder then you think, take a good look at picture of crater lake from the rim looking down, then ask yourself, "How the heck do I get all the heavy equipment down the crater rim without Polluting the lake or Casusing man made landslides durign road construction that triggers the CO2 release anyway."

Even then, if release wells are someone constructed, releasing the C02 in the amounts that would change danger levels, would take many well's a few centuries of operation to have any effect on reducing the danger. It would be a most excelent source of power generation however, if you could get around the national park status (which would be very unlikely to happen) to build release well's and power plants.

dgavin
2012-Mar-01, 09:42 PM
I am curious to know if anyone knows of a confirmed exposure of a collapsed magma tube that was at one time at a great depth?

While these were never at 'Great Depth' and they are not that old, Sawyer Caves in Oregon is about as close as you'll get I think. The caves are still largely unexplored, though I've been inside the bigest one, you can't go back to far as it

http://oregoncaves4u.com/sawyers_cave.html

http://paultower.wordpress.com/2010/10/10/sawyer%E2%80%99s-caves/

jlhredshift
2012-Mar-02, 03:20 AM
While these were never at 'Great Depth' and they are not that old, Sawyer Caves in Oregon is about as close as you'll get I think. The caves are still largely unexplored, though I've been inside the bigest one, you can't go back to far as it

http://oregoncaves4u.com/sawyers_cave.html

http://paultower.wordpress.com/2010/10/10/sawyer%E2%80%99s-caves/


Thanks

dgavin
2012-Dec-07, 09:06 PM
A New crater lake siemograph is online. And it's picking up a lot more then the old one's did, as this baby is on the peak of Scott's Moutain, (which is a small mountain thats on Mt. Mazama itself half way up the east slope).

The link i'm posting show winds storms, ice fracturing, and glacier movement tremors on the one day. Not sure how long these url's will be good for, as they are from the new PNSN website as well.

http://www.pnsn.org/seismogram/2012/12/4/clms/ehz/cc/ (http://www.pnsn.org/seismogram/2012/12/4/clms/ehz/cc/)

dgavin
2013-Aug-01, 07:03 PM
Two more siesmographs are now active at Crate Lake. One directly upon Wizard Island inside the caldera, and another on the lake shore next to the Boat Tour docks along the North Rim.

CJSF
2013-Aug-02, 12:12 PM
Active, as in newly activated/installed, or active as in recording new tremors?

CJSF

dgavin
2013-Aug-03, 02:25 PM
Recently installed and brought online. There is a lot of noise on these two and Scott's peak station, that appear to be ice and snow breakage, but nothing unusual I've seen so far.

dgavin
2013-Aug-09, 07:16 PM
All Seismograph transmissions form the Crate Lake Region were lost on Aug 5th.

The two new stations should be fine, but it looks like the transmitter near Mt. Scott was taken out, likely by a fire activity in that region. No Offical word of the loss of these signals from USGS yet, but fire is the most likely reason.

John Mendenhall
2013-Aug-10, 02:07 AM
Enjoyable posts. Gavin, thanks.

dgavin
2013-Aug-18, 04:40 PM
The three seismograph stations at Crater Lake are still down. I took a look at some recent arial photo's of Mt. Scott. There doesn't appear to be any hint of fire damage around the mountain. It's possible a lightning hit took out the radio transmitter, or it's solar panels. Nothing on it from USGS in weekly reports yet, so I have no solid explanation as to why the feed was lost.

dgavin
2013-Sep-06, 06:45 PM
Crater Lake Seismographs came back into service on Aug 20th. Nothing from USGS about the failure, so it must of just been a standard equipment failure.

BigDon
2013-Sep-13, 11:59 AM
Wait a sec!

Crater Lake is a carbonated lake? Why is this the first time I've heard of this? (After doing a report on the Lake Nyos disaster I've been fascinated by the subject.)

and why doesn't Crater Lake naturally turn over twice a year with the season changes like other temperate lakes? That's one of the reasons "most" lakes don't do that.

And I thought lakes that were at risk for limnic eruptions required cold water bottoms?

If Crater Lake were saturated then that 6F to 12F bottom warming should have the whole area primed to blow.

A suffocate everybody from Bend, Oregon to the California border...

BigDon
2013-Sep-13, 12:12 PM
Showing it in real time is not hard, no, giving adaquate warning that such an event might happen, is near impossible, again as there is no precursor activity.

Fixing it is a lot harder then you think, take a good look at picture of crater lake from the rim looking down, then ask yourself, "How the heck do I get all the heavy equipment down the crater rim without Polluting the lake or Casusing man made landslides durign road construction that triggers the CO2 release anyway."

Even then, if release wells are someone constructed, releasing the C02 in the amounts that would change danger levels, would take many well's a few centuries of operation to have any effect on reducing the danger. It would be a most excelent source of power generation however, if you could get around the national park status (which would be very unlikely to happen) to build release well's and power plants.

Ummm, Lake Monoun, the first known killer lake has been completely degassed and rendered safe. Four one meter diameter fountain pipes keep Lake Nyos at equilibrium, matching input with output.

And matters of concern about polluting the lake are absurd when weighed against the prospect of a million human beings suffocating in a matter of hours.

Were you really considering that as an obstruction? It's not like the place will still be pretty after an event like that.

dgavin
2013-Sep-14, 03:48 PM
BigDon, all good questions.

The main reason the lake doesn't turn over is it's depth and low temperature. Its very stable, and the information I read is it might have enough pressure for hydrates to forms as well as CO2 saturation. That is still being investigated. It would take a very serious landslide to cause a mass release of it's built up C02. Likely something on the order of part of the rim actually collapsing, would be my guess.

Any effort to harvest or release the CO2 would in effect pollute the lake. It is the purest lake in the work, that has no inlet or no outlet, with a visibility factor recently measured to 148 feet deep. They are likely not going to attempt something like that, until more assessment of the stability of the CO2 and other gasses can be made.

From my understanding the lake may be deep enough that the C02 saturation is potential stable (except during an eruption), but that it would take more research with deep water probes to make sure of that. They don't send research probes into it very often, once per decade or so, as even that minor activity causes pollution. So a lot of you question I think will not have good solid answers until more research is done on it.

profloater
2013-Sep-16, 09:16 PM
question about crater lake; I understand it is only rain and snow melt, is there any route for salts to enter? Salt stabilises by surface concentration with evaporation and then sinks. A salt profile can overcome convection and the natural turnover, but I thought crater lake to be exceptionally pure water?

dgavin
2013-Sep-17, 02:03 PM
Best sources I could find.

In summary, The dissolved-solids concentration is about 80 ppm, made up mostly of silica, calcium, sodium, and bicarbonate (table 13). However, Crater Lake also contains significant concentrations of sulfate and chloride (about 10 ppm of each) not usually found in the surface water of humid mountainous regions.

There also are areas that are iron rich and sport bacterial blooms, where the water is typically 15c warmer, indicating hydrothermal activity.

http://www.craterlakeinstitute.com/online-library/crater-lake-hydrology/chem1.htm

http://chemoc.coas.oregonstate.edu/~bobcollier/CLhydrothermalSite/ (http://chemoc.coas.oregonstate.edu/~bobcollier/CLhydrothermalSite/)

profloater
2013-Sep-19, 08:23 PM
many thanks, reading through that it is clear there is a source down there and its salty nature will (or may) keep it low down. I surmise the densest water at 4 C in winter does not actually reach the bottom but falls to the salty zone. What a fascinating place!

dgavin
2013-Sep-20, 02:19 PM
Deep Lakes, are fascinating just on their own. It's amazing how many small but distinct areas of chemical, biological, and thermal nature form in them. Put a deep lake on top of a huge volcano, and yeah, it really sort of is like the icing on a cake.

And you are right about the 4c water not reaching the bottom. The bottom of the lake is up to 6c warmer, then the area's above it. That's also another indication that Mt. Mazama is still Hydrothermally active. It's also the reason they are not sure it forms hydrates. The water is cool and deep enough barely for hydrates to form, but, as those hydrates form, and then settle into warmer waters at the bottom, they may actually then dissolve.

BigDon
2013-Sep-24, 08:01 PM
Mr. Gavin, one of my friends who is a regular lurker here informed me that some of my earlier post in this thread came off a little hostile.

I apologize if that was what came across. I was merely distressed by the notion of the hazard a carbonated lake represents, and one so close to home to boot.

I've always appreciated your volcanic posts and updates since you began doing them.

dgavin
2013-Sep-26, 02:49 AM
It didn't bother me, I'm just a amateur Vulcanologist, and not involved with USGS. Crater Lake is just one of those environmentally touchy area's. They technically could send in a lot of probes to find out what's going on quickly. But it would totally ruin the pristine nature of the lake. So I don't see that happening unless the lake chemistry starts altering subtly first. That's really how someone will know there might be a issue there that needs attention, is the lake chemistry will start to change in subtle ways. More Sulfurs, silicates, iron and copper.

dgavin
2013-Oct-25, 07:21 PM
3 confirmed quakes today at crater lake, the largest being only .8 mag (point 8 mag not 8.0 mag), the other two less then .1 Mag. They only showed up on 2 seismograph stations, so no percise location is posible, thus they are not on the USGS or Google map based EQ spotters.

Examining the webicorders myself, I was able to determine the strongest and earliest seen signals were at the Wizard Island seismograph station. Then next on the Cook Cove Seismograph station inside the north rim at lakes edge. The Mt. Scott station on the south flank did not show the events.

So best guess puts them inside the caldera someplace, likely near Wizard Island.

dgavin
2013-Oct-26, 10:56 PM
Two more quakes today at crater lake, unconfirmed, and again on the less then .1 Mag range. These only showed up on the Wizard Island station as the other two stations were saturated by wind storm readings.

dgavin
2013-Oct-28, 07:12 PM
There may have been one more quake here yesterday, similar as a less than .1 Mag, however it was hard to pick out as the seimographs are saturated by wind readings, and this one is more likly a miss reading on my part. Wind saturation has continued through today, so not sure how many more updates there will be on Crater Lake. The very tiny quakes could be over with by the time the storms settle down.

dgavin
2013-Oct-30, 07:45 PM
There was nice looking rock slide signature on Cook Cove Seismograph station today, but it's been quiet otherwise. Don't really expect much more to report on Crater Lake in the next few weeks. The stations are still fairly wind saturated.

dgavin
2014-Apr-14, 06:56 PM
From USGS friday report:
A swarm of approximately 20 very small VT-type earthquakes occurred in the southeastern part of the Crater Lake caldera over the space of about 5 hours on April 8th.