Taking a closer look at the Yellowstone earthquakes over the last week

There has been a ... ahem ... healthy discussion of Yellowstone's current earthquake swarm on Eruptions as of late. We've now reached ~1,500 measurable earthquakes over the last 11 days. The latest reports of the continuation of the swarm isn't going to make anyone happy, but still, there are no signs that (a) this is out of the ordinary and (b) indicates magma making its way to the surface. In fact, if you plot the earthquakes since the 22nd of January, the depth appears to getting, well, deeper:


This plot shows the earthquakes listed on the USGS earthquake page since January 22 (oldest to left, youngest to right) plotted against depth. If anything, the earthquakes seem to be becoming more restricted in their depth around 10-10.5 km and definitely not heading upwards. This is not to say that they won't, but with the evidence right now, the earthquakes seem to be pretty stably around 10-11 km depth. That, to me, seems to back up the USGS/YVO assertion of a tectonic origin - faults at depth (more or less) - rather than magma/liquid moving towards eruption (combined with the fact that the earthquakes are staying approximately the same magnitude range ~ 1-3).

However, you never know with a system like Yellowstone - nothing can really be considered "unrelated" to the caldera and we don't have a lot of evidence of how large caldera systems might behave before an eruption. However, remember, Yellowstone is just a big caldera - and we have experienced other caldera-related eruptions like Katmai/Novarupta in 1912 and Chaiten in Chile in 2008 - we're definitely not working with no idea what to expect. We can also model the potential types of behavior of a caldera if it were headed to eruption to at least give us an idea of what might happen, seismically speaking, if an eruptive sequence was beginning.

This earthquake swarm is clearly fascinating and well worth our time and attention. However, delving into conspiracy theories and fear is definitely not the way to go. I'll try to stay on top of the unfolding events, so watch this space if anything changes!

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Thanks, Erik. Seems like most agree that Yellowstone could erupt, but it doesn't look like it right now given the data. I have been trying to say that we can enjoy the experience of keeping tabs on Yellowstone and any other caldera or volcano out there and learn from it. We can also be prepared for emergencies. The usual ones we know about and then maybe be aware of the forces that move terra firma which isn't so firma. Like I said, I live near volcanoes and faults and in a fire prone area. Things to think about and have some idea what I would do in any of these cases.

BTW, my computer didn't register the plot you posted. I'm not sure why, but it didn't. The number of quakes reminds me of Long Valley when it was going to town. I remember checking the quake map and there were over 1000 for a week there at one time. I don't remember the year, but it was in the mid '90s. I remember, too, all the hullaballoo it created because of the resurgent dome area. It is still 80cm higher than it was in the '70s.

Seems like both of the calderas have acted simularly in recent times though Yellowstone is more active.

Let's keep watching and waiting for the next event and hope it doesn't do any harm to anybody.

BTW, which is the largest caldera? I though it was Toba and Yellowstone had the largest or next to the largest magma chamber.

How is the current swarm effecting geyser activity in the park? Any changes?

How many square miles of earth are ejected? Would not the pressure to blow 10 cubic miles up have to be below 10 cubic miles down?

By Harlow Stephenson (not verified) on 28 Jan 2010 #permalink

To answer my own question and postulate an idea, could someone use air pressure under clay or buried plastic to mock a super volcano eruption to give us a better idea of what to watch for as a warning sign?
Have any man-made test been done like on Myth Busters or in any Collages or Battle Test Grounds maybe?

By Harlow Stephenson (not verified) on 29 Jan 2010 #permalink

in most explosive eruptions a large percentage of the erupted material is the erupted magma itself and not any overburden. The volumes from the truly large eruptions we see in the geological record are direct reflection of the amount of magma involved and not the amount surface material it blasted through.
If magma was behind the swarm we would see rapidly ascending quake foci prior to the eruption. Anything larger than a localized event would start producing quakes in other locations.
Erik, I think this would be a good time to recommend some books for the non-geologists that explain a range of volcanic activity.

Isn't this EQ swarm possibly related to HAARP? I've been monitoring their Magnetometer Induction graph and it eerily coincides with these events.

Funny thing about HAARP. I have a HAARP baseball cap because my dad has done work on HAARP with the Air Force. Does that mean I'm part of the conspiracy. I hate to burst people's bubbles, but I doubt HAARP does anything in the way of causing tectonic events.

The real issue that all HAARP conspiracy theorists fail to grasp is that the RF out of HAARP just doesn't have the energy to move rocks. Radio is a very poor way to transmit energy to rocks, and it is very clear, no mater what the Induction Magnetometer shows (which is actually quiet during this period), that HAARP is not causing any tectonic activity.

A question for Erik: could the current earthquake swarm be caused by moving hydro-thermal fluids rather then moving magma or regional tectonics? Do we know what the focal mechanisms are for these earthquakes?

It is well known that the RF is just the carrier.
MANY understand what they are really doing.
YOU need to go do your homework !

By OLgreyhair (not verified) on 29 Jan 2010 #permalink

@OLgreyhair: About HAARP; What are your references?

Thanks, Erik for posting about books on volcanology. I don't have a book on that subject yet and I want to read about it since it has been more than 30 years since I took geology and need to get something up to date. Then I will have a better idea of what everybody is talking about. :-)

Here is one for you: when I took geology, the teachers had the class go to a road cut and take a good look at it. There was a dike in it and I saw a rock that was part of that dike and I took it for my collection. I still have it and they told me that it was metamorphic and I took it out of an ignious dike! I told them that and I wish you could have seen the puzzled look on their faces! Rather comical, but sometimes you get things like that. Who knows? Maybe there was some heat and stress on that dike just at that spot where that rock was. That is all they could come up with. Leave it to me to find something totally out of the ordinary as far as they were concerned.


Quantum energy transfer has been an ongoing research model for the military for years now. This technology is only recently been in it's infancy of develop in the civilian world. HAARP uses RF to TRANSMIT the energy. RF itself is useless against hard targets, but the energy it CARRIES, much like a soprano shattering a glass across the room, the energy waves can likewise damage strata...

Very interesting. I wonder, do you have similar data from any past periods? Also, the data in your graph look like they could be indicative of a sawtooth waveform. I'm not a geologist, but I think I remember reading that magma flows and oscillations between gas/magma interfaces can cause sawtooth patterns in their seismic output. Is there any chance that your data are showing magma flowing deep under the ground at yellowstone?

By Graham Lau (not verified) on 30 Jan 2010 #permalink

Olg, Stew: dont worry about HAARP, we have WAY scarier stuff than that. PS ----ALL energy transfer is quantum.

I think the biggest caldera is the Island Park Caldera which is the Yellowstone eruption from 2.1 Mya, which measures 40 x 58 miles. It only ejected 2500 cubic kilometers of stuff tho, so officially the Largest Eruption was La Garita in Colorado, only 22 x 47 miles of collapsed caldera, but it ejected 5000 cubic kilometers (1200 cubic miles) of ash, etc.

I've yet to hear conclusively whether these are primarily huge single vent volcanics, followed by various collapse mechanisms into the depleted magma chamber, or if the stuff comes out of multiple vents which help cause the fracturing and collapse. A lot of times the collapse caldera re-fills with magma after the initial large eruption.

Fitz, great question. I always wondered the size and location of the Yellowstone Vents. I can't imagine a vent tens of miles in diameter.

By Dasnowskier (not verified) on 31 Jan 2010 #permalink

I can imagine a lot. Once the magma chamber collapses, any further erupting (which is normal I gather) comes from the perifery and whatever is left of the original vent or vents. And then later it can slowly fill with lava.

I've seen a lot of diagrams and cross sections of various collapse mechanisms. Some caldera collapse in a radial pattern. Some collapse more on one side, some split down the center like a trapdoor.

Yellowstone has calderas inside older larger calderas, same for La Garita. I guess a lot of the Snake River Plain is a chain of old lava and ash covered calderas. I cant find much info on those, or on the likely numerous small eruptions from YS since the last big eruption 600,000 yrs ago.

@Fits: I think the Snake River plain is from several vent systems that erupted the last time about 2000 years ago. I have been to the Craters of the Moon and you may find more info on that area if you haven't checked. On the plain itself are three cinder cones (I thinkthat is what they are) and you can see them from miles. The lava flows go for miles and miles. I don't remember the milage, but it is quite a ways.

I am going to have to study some more about Yellowstone because at the moment, I just know that it is a hot spot and there are craters or calderas that have come before the current one.

Where is La Garita and what is the nearest town? I am not familiar with that.

Seems that if I keep coming back to this blog I will become a geologist. LOL

La Garita is a part of the San Juan Volcanic field in Colorado. It is on the west edge of the San Luis Valley about 40 miles or so east of Creede. There are a huge number of Calderas in that area including Silverton. It is also the location of extremely valuable mineralization, Creede, Lake City, Silverton, and Telluride were mining camps. (Also one of the most beautiful parts of the US)

@Lyle: Thank you for letting me know where these calderas are. I had no idea there were calderas in Colorado. I should have know that, but I haven't studied Colorado geology. I am going to have to take a look at that. I have been to Colorado a few times in Bolder and drove over the summit in Rocky Mt. National Park out of Estes. It is beautiful. Got to see the mountian goats one time and the big horn sheep on another trip. There was a rarity out of Estes as there was a herd of the big horns of about thirty sheep. I was happy I got to see them.

@Fitz: Yes, I know about the torment of a rookie rockaholic. I have been a rockhound since I can remember!

Thanks for taking the time to look that stuff up. It put things in perspective for me. I knew about Long Valley and how far they have found the Bishop tuff. The Lava Creek ash sure spread a long ways. Was that the eruptions ~600,000years ago? And Mazama wasn't that small, either. Makes Mt. St. Helens look like a minor burp in the earth's digestive track.

I have looked at the new Yellowstone "Plume" articles published in 12-09. It shows the plume extending downward to the northwest towards Montana from around 40 miles to a depth of 410 miles. The geologists that published the plume document think it goes to the core/mantle boundary. The magma chamber below Yellowstone is around 4 miles to 10 miles deep and is fed by "blobs" of hot rock breaking off the plume and rising upwards to the chamber at 10 miles deep.

The below UTAH http site shows that the 2/2-2010 earthquakes are now at a depth of around 5 km, which puts the most recent quakes in the magma chamber. In your most recent 1-28-2010 entry above, you state that the quakes are around 10 km and don't seem to be moving up to the chamber.

How do you read the data from early February that shows the quakes possibly moving upwards to the magma chamber around 5 km?

Earthquake info below


yellowstone magma plume article below


burma plate, earthquake, haiti earthquake,middleeast plate movement,the ground is rumbling in the great rife valley of africa the alantic sea floor is unstable due to the burma plate uplife 2004.seeing a quake / volcano near spain
cause a land slide into the alantic the wave would be so large to cause a weight shift of earth!this will cause the the caldaro of yellowstone to flow.Its only waking up after a long sleep.the ENTIRE caldaro is shaking.something is to come of it californa is a floating bough on water waiting for a quake to break it off sliding into the bay of mud. stay close to god and pray. 2012 watcher 2012
The Earth Is Angry

The fault may be feeding the magma reservoir. But, in order for an imminent eruption you need three things. Ground deformation, increased SHALLOW magmatic quake swarms and increase in volcanic gasses. So far its just like adjusting your position while you're sleeping. Somewhat soundly. Just watch it close and shhhhhhhhh! Avoid waking it up.

By Grace Messenger (not verified) on 19 Nov 2010 #permalink