6.8 Mag Earthquake Strikes Myanmar

A 6.8 magnitude quake struck Myanmar today near the volcanic Singu Plateau, a trachyandesitic lava field fed by fissures near the fault line in question.  So far 13 people have been confirmed dead. The epicenter of the quake was about 15-20 miles NNW of the volcanic center, and multiple aftershocks of 5.0-5.8 have now occurred at the volcanic center, less than 2 miles away at depths of about 10km.

Screenshot of Google Earth with USGS real-time quake overlay.

The quake occurs as newly re-elected US President Barack Obama is scheduled (in about a week) to arrive in the war-torn nation formerly known as Burma for talks with their newly elected president Aung San Suu Kyi in regards to helping the fledgling democracy improve their country and better interact with the international community.

It is unclear at this time whether this quake will spur any activity at the Singu Plateau, but as it has not erupted for several millenia, it is probably not likely, although it is remotely possible. The Singu Plateau is not a closely stidied volcanic system. It exists on the fault line that extends South through the region, and consists of fissure vents that tend to send lave West of the vents. It is not clear the last time it had an eruption, although the Smithsonian Global Volcanism Program characterizes the Singu Plateau as Holocene in age:


"The Singu Plateau volcanic field, also known as Letha Taung, is a Holocene basaltic trachyandesite lava plateau in north-central Burma, north of the city of Mandalay. The lava flows originated from fissure vents and cover an area of about 62 sq km"

No age is given for the last eruption.

A post from volcanologist John Seach is quoted as saying:

"A magnitude 6.6 Earthquake hit 36 km north of Singu volcano, Burma on 11th November 2012. Two magnitude 5.0 aftershocks occurred 8 and 13 km from the volcano two hours later. The last eruption at Singu volcano is unknown but probably occurred in the past 10,000 years, which makes it an active volcano on a geological timescale."

As of now there have only been 4 major aftershocks, a 5.8, a 5.6, and two 5.0 quakes. Three of these have occurred within the volcanic region.

Magnitude 7.4 Quake Strikes Guatemala

A Magnitude 7.4 earthquake has just struck off of the coast of Guatemala in another Pacific subduction quake. There were no immediate reports of damage, and the inland appears to have been spared major shaking due to the mountain ranges that seem to have served as a buffer. The quake occurred off of Guatemala's west coast at a depth of 41.6km, which is also why the surface intensity must have felt a bit lower (shallower quakes are typically a lot more damaging).

Google Earth snapshot with USGS real time quake plugin.

There are no immediate detailed reports for this quake. A blog on CNN is the most up-to-date at this time. There was no threat of a tsunami according to the Pacific Tsunami Warning Center, who's statement is below:

"TSUNAMI INFORMATION STATEMENT NUMBER 1
NWS PACIFIC TSUNAMI WARNING CENTER
EWA BEACH HI 643 AM HST WED NOV 07 2012
TO - CIVIL DEFENSE IN THE STATE OF HAWAII SUBJECT - TSUNAMI INFORMATION STATEMENT
THIS STATEMENT IS FOR INFORMATION ONLY.
NO ACTION REQUIRED.

AN EARTHQUAKE HAS OCCURRED WITH THESE PRELIMINARY PARAMETERS ORIGIN TIME - 0636 AM HST 07 NOV 2012 COORDINATES - 14.0 NORTH 92.2 WEST LOCATION - OFF THE COAST OF CHIAPAS MEXICO MAGNITUDE - 7.5 MOMENT EVALUATION

BASED ON ALL AVAILABLE DATA A DESTRUCTIVE PACIFIC-WIDE TSUNAMI IS NOT EXPECTED AND THERE IS NO TSUNAMI THREAT TO HAWAII. REPEAT.

A DESTRUCTIVE PACIFIC-WIDE TSUNAMI IS NOT EXPECTED AND THERE IS NO TSUNAMI THREAT TO HAWAII. THIS WILL BE THE ONLY STATEMENT ISSUED FOR THIS EVENT UNLESS ADDITIONAL DATA ARE RECEIVED. "

There are many volcanoes int he area, as this epicenter lies along the so-called Pacific Ring of Fire. Volcanoes in the area include (from NW to SE):

Tacaná
Tajumulco
Santa Maria (currently erupting)
Almolonga
Santo Tomás
Tolimán
Atitlán
Fuego
Acatenango

Quakes of this magnitude can affect seismicity in active volcanoes, especially ones that frequently erupt, or have a very pressurized magma chamber. It is unclear at this time whether or not this will be the case.

Very Large 7.7 Mag Quake Reported Off Of Canada

A magnitude 7.7 Earthquake has struck off of Canada's West Coast near Graham Island Queen Charlotte Island. The depth was a shallow 9km deep, along the Pacific subduction zone. It is unclear if there was any damage or if a tsunami has been generated. The quake occurred at 8PM which is only a few minutes after I am writing this. Below is a screenshot of the epicenter location.

Google Earth/USGS snapshot of location of 7.7 mag quake.

Aside from the linked article above, this quake is so fresh that nobody yet knows the implications. I will update this article as more info becomes available.

.

Image from USGS.gov detailing the shake strength of the quake.

UPDATE: According to WFAA a tsunami alert was issued from Vancouver Island, British Columbia to Cape Decision, Alaska. Residents are urged to move to higher ground. This is likely a precaution but if you are in the area please do not hesitate to seek higher ground.

A mag 5.8 afterschock occurred a few miles SW of the epicenter.

The island is lightly populated by what appear to be logging towns. Looking at Google Earth reveals several towns in the area nearest the epicenter. Those towns are:

Sewell Inlet
Skedans Village
New Clew
Sandspit
Skidegate
Queen Charlotte
Tlell
Port Clements

It is likely that these towns sustained some damage, but reports will likely be slow to come from the region.

Here is an update from the Tsunami Center:

From: tsunami-information-ioc@lists.unesco.org
Date: October 27, 2012, 11:14:14 PM EDT
To: IOC_Public_Lists@ptwc.noaa.gov
Subject: [Tsunami Message - IOC] Tsunami Information Bulletin
Reply-To: tsunami-information-ioc@lists.unesco.org

TSUNAMI BULLETIN NUMBER 001

PACIFIC TSUNAMI WARNING CENTER/NOAA/NWS ISSUED AT 0313Z 28 OCT 2012 THIS BULLETIN APPLIES TO AREAS WITHIN AND BORDERING THE PACIFIC OCEAN AND ADJACENT SEAS...EXCEPT ALASKA...BRITISH COLUMBIA... WASHINGTON...OREGON AND CALIFORNIA. ... TSUNAMI INFORMATION BULLETIN ... THIS BULLETIN IS FOR INFORMATION ONLY. THIS BULLETIN IS ISSUED AS ADVICE TO GOVERNMENT AGENCIES. ONLY NATIONAL AND LOCAL GOVERNMENT AGENCIES HAVE THE AUTHORITY TO MAKE DECISIONS REGARDING THE OFFICIAL STATE OF ALERT IN THEIR AREA AND ANY ACTIONS TO BE TAKEN IN RESPONSE.

AN EARTHQUAKE HAS OCCURRED WITH THESE PRELIMINARY PARAMETERS ORIGIN TIME - 0304Z 28 OCT 2012 COORDINATES - 52.9 NORTH 131.9 WEST DEPTH - 10 KM LOCATION - QUEEN CHARLOTTE ISLANDS REGION MAGNITUDE - 7.1 EVALUATION A WIDESPREAD DESTRUCTIVE TSUNAMI THREAT DOES NOT EXIST BASED ON HISTORICAL EARTHQUAKE AND TSUNAMI DATA. THE WEST COAST AND ALASKA TSUNAMI WARNING CENTER WILL ISSUE INFORMATION REGARDING ANY LOCAL TSUNAMI THREAT TO COASTS NEAR THE EARTHQUAKE EPICENTER.

THIS WILL BE THE ONLY BULLETIN ISSUED FOR THIS EVENT UNLESS ADDITIONAL INFORMATION BECOMES AVAILABLE. THE WEST COAST/ALASKA TSUNAMI WARNING CENTER WILL ISSUE PRODUCTS FOR ALASKA...BRITISH COLUMBIA...WASHINGTON...OREGON...CALIFORNIA.

The information provided on this email service does not originate with UNESCO. UNESCO is transmitting this information on an unofficial basis. The official warning messages are sent by governmental authorities through the Tsunami Warning Focal Points (TWFP) and the designated national authorities. UNESCO does not warrant, guarantee, or make any representations regarding the timeliness, currency, correctness, accuracy, reliability, or other aspect of the characteristics or use of the information available through this email service.


UPDATE:

CNN is now covering the story and has a live blog of all developments at http://news.blogs.cnn.com/2012/10/27/quake-with-a-magnitude-of-7-7-strikes-off-canada-coast/?hpt=hp_t1

UPDATE

so far 13 aftershocks ranging from 4.0-58 have occurred. Likely aftershocks will continue for up to a week or longer, with diminishing magnitudes.

Large And Shallow Earthquake Swarm Near Aniakchak Volcano

Aniakchak volcano in Alaska is one of the largest, and most active volcanoes in the Aleutian arc. The volcano contains a 10km wide caldera, with multiple cinder cones occupying the ~3400 year old caldera floor. The last eruption of Aniakchak occurred in 1931, which marked the only known historical eruption of the volcano.

A large earthquake swarm struck approximately 25 miles NE of Aniakchak on August 3-5, centered between Aniakchak volcano and the lesser-known Yantari volcano (which apparently had a very Mt. St. Helens like eruption in pre-history). The largest quake was a 4.7 magnitude quake at a depth of around half a kilometer (which is very shallow). Many other shallow quakes, some with similar magnitudes have occurred (see the below image) since.

Google Earth plugin with USGS real-time overlay enabled showing the location of the quake swarm

The depths of most quakes in the area are usually some hundreds of KM deep, as this is a subduction zone where one plate slides underneath the other. Occasionally this process generates a magma vein, that results in dike intrusions and the birth of most of the world's stratovolcanoes.

This quake swarm is curious due to its location and the very shallow depths. New volcanoes have been born in Alaska in the past, sometimes with disastrous results such as the eruption of Novarupta, the largest eruption of a US volcano in recorded history. While it is likely that this is a magma dike intrustion into the crust, it is impossible to say what might occur if the swarm does not return, or no new magma is injected into the crust. Most dike intrusions do not result in an immediate eruption, and some times they never do.

In any case, I will be keeping a close eye on this, and possibly email AVO about the swarm and see if they were aware of it (which I am sure they were) and whether they might be able to shed some light on it for our readers. Stay tuned!

*****UPDATE 8/9/2012*****

Another single quake at a depth of 5km measuring 2.5 occurred today in the area. This is the first aftershock/tremor in a few days. I have contacted AVO requesting information on the current swarm, and hopefully will hear back from them soon!

*****UPDATE 8/10/2012*****

AVO responded to my email with the following response:

"They're regional tectonic earthquakes. We have no indication that these earthquakes have anything to do with volcanism.This series of earthquakes, at this time, is not alarming to us."

So it appears that there may be several faults criss-crossing the Aleutians that occasionally have these shallow types of quakes occur, even very near active volcanoes.

Swarm Of Quakes Rattle Los Angeles, CA

A series of moderately sized earthquakes and associated aftershocks hit the Los Angeles (Yorba Linda) area in California today and yesterday, with two quakes registering 4.4 and 4.5 on the Richter scale being the largest tremors. Residents as far south as San Diego County reported feeling the quake, and near the epicenter it was reported to feel quite strong. The quake depths were from 10km-8km for the largest tremors. Many shallower aftershocks, most at or around M2.2 (but some at 2.9) have occurred, and are still occurring as of now.

Los Angeles is no stranger to earthquakes, and as such, has building codes that normally prevent any damage. In California, most buildings must be built to be able to withstand up to a magnitude 8.0 quake as a building standard.

Interestingly enough, the quakes did not occur on the famed San Andreas fault line that extends from Baja California, Mexico, to central California in the US. These quakes occurred some 35 miles SW of the nearest point to the fault at Cajon Junction. These quakes occurred on a smaller fault that runs under Yorba Linda. This fault line is quite small compared to its larger, more violent neighbor, the San Andreas, running only tens of miles in a NW/SE direction. (Given that this is a volcano blog, I should note that these quakes are in NO WAY related to any type of volcanism).

It is likely that more smaller aftershocks will follow for a few days in the area as the fault settles down. It is possible that these quakes may destabilize other faults in the area, however at this time this is only a 'maybe', as scientists still struggle to really figure out how parallel faults affect one another. Earthquake dynamics are highly complex with many factors that go into causing them, and even more factors in the aftermath to consider. 

Another 6.3 Quake Hits Mexico

A magnitude 6.3 quake struck the Oaxaca region of Mexico today, near the area where the large mag 7.6 quake hit a couple weeks ago. This is the largest aftershock thus far from the 7.6 tremblor. Housing and property were damaged by the large quake, however injuries and fatalities were thankfully very low due to citizens being well prepared for evacuating. Mexico, like the West Coast of the US, is part of the Pacific Ring of Fire, an arc of subduction faults and volcanoes spanning the rim of the Pacific plate.

The quake was centered in the Western corner of the state of Oaxaca, approximately 2 miles away from the epicenter of the 7.6 quake. The quake was felt as far away as Mexico City due to the composition of the earths crust (a mix of clay sediments, and volcanic ash), which is a good conductor for seismic waves.

No volcanic unrest has been associated with these quakes. Several rumors were circulated that Popocatepetl might have been 'disturbed' by the shaking, however the volcano continues to act normally, only occasionally puffing our steam, or small amounts of ash.

Mexico is very familiar with earthquakes and volcanic eruptions. Central Mexico is home to thousands of cinder cones, vents, stratovolcanoes, and calderas. Popocatepetl is Mexico's most active volcano, having erupted fairly regularly in historical time.

The current seismicity is associated with the collision and subduction of the Pacific Plate and the North American plate, and is not volcanically related. Some quakes can and do disturb volcanoes, and can destabilize magma chambers, but most volcanoes in Mexico are long dormant, or too far from the quake epicenter to be affected in any serious way, so there is probably no risk of heightened volcanic activity as a result of the recent quakes.

*****UPDATE*****
The quake was downgraded to a 6.0 later by USGS. No reports of damage or injuries have been made apparent.

Magnitude 7.6 Quake Strikes Mexico [UPDATED]

A Magnitude 7.6 earthquake occurred in Southern Mexico today, with the epicenter between Guerrero and Oaxaca. The quake was felt as far North as mexico City, which is approximately 200 miles from the epicenter. Shaking was extremely violent at the epicenter, and for a radius of around 100 miles.

No current reports of damages or injuries, however news is slow to come out of the region, and there will likely be many follow up reports on this.

*****UPDATE*****

As expected, reports have started to flood in from Mexico (keep in mind, I wrote this post the second the quake popped up on my Google Earth USGS plugin), and the damage is striking.

Many hundreds if not thousands of homes have been damaged or destroyed. 11 people have so far been confirmed dead, which is actually very good considering the magnitude of the quake and the area that it struck. This number will likely rise however, but at this time it does not appear that as many people were hurt or killed. In 1985, a very large and shallow 8.0 quake hit Mexico City, killing up to 10,000 of its citizens.

The quakes in central and Southern Mexico are especially damaging due to the composition of the ground... volcanic ash and clay deposits. These materials conduct seismic waves with ease, and when an earthquake hits, can liquify the ground, sinking buildings. This liquifaction effect was very apparent in video from Japan when the 9.0 quake and tsunami (oh yes, throw int hat nuclear disaster at Fukushima too...) struck. One video showed black water spouting out of sidewalks and lawns.

The 7.6 (some news organizations are incorrectly reporting the magnitude as 7.9) quake has spawned many aftershocks. At this point in time, 17 aftershocks, all ranging from 4.1-5.3, have struck near the area of the initial quake. As a Southern Californian, used to many quakes, I can say from firsthand experience that a 5.0 quake is still no joke, especially if you're near the epicenter. I was present in San Diego when a magnitude 7.2 quake hit Mexico near Mexicali/El Centro (I happened to be camping not 20 miles from the epicenter that day, and had planned to explore the mud caves out there... thankfully my friends and I couldn't find them, or we might have been the ONLY casualties of that quake on the US side of the border!!), and saw the ground ripple. Where I was when the quake actually hit was near the coast, and USGS says that would have felt like a mild 6.0 quake.... nothing mild about it.

Thankfully, Southern California has great construction codes that allow our buildings to nearly shrug off anything up to an 8.0... anything larger would be pushing it. The same is not true in Mexico, which is a very poor country. Most buildings are built without strict adherence to earthquake code, are very old, or are built illegally, making earthquakes that much more dangerous in the region.

Aftershocks and other quakes will happen in the area for a while. The 7.2 quake of Easter 2010 has left the entire Southern California/Northern Baja California fault system in a state of perpetual flux, generating tens of small quakes every day. In another blog post I talk about the recent spate of activity at the Salton Sea, which looks like magma dike intrusion, which began to occur after the quake. Not many people know it, but the entire area from the Salton Sea to Cerro Prieto is a spreading fault, and will erupt in the future *(the newly minted California Volcano Observatory lists the area as a high threat for future eruptions).

Anyhow, welcome to the Pacific Ring of Fire. Subduction quakes are simply a fact of life out here!

Golden Trout Creek Volcanic Field Experiences More Earthquakes

The quake swarm at Golden Trout Creek in California has added several new tremors today in what is looking more and more like magma dike intrusion. The quake area (as shown in a previous post) is less than a mile away from two separate hot springs; Joran Hot Springs, less than 1 mile from the swarm area, and a thermal area to the West of the quake region (or what appears to be one on satellite). The quakes started out at depths of around 8KM, and in the course of one day have progressed to a magnitude 2.3 at a depth of 3.8KM.

There were four magnitude 2.0 or greater quakes today in the area, with many smaller tremblors dotting the area. Aside from the obvious trend in quakes getting shallower, the area being very near thermal hot springs begs the question, "Is this Pleistocene/early Holocene volcanic center having a magma intrusion"? My guess at this point is yes, however the newly minted CalVO (Formerly LVO) has yet to publish any analysis. This area does have active fault lines, and it could be that this is only tectonic, however the area is known for at least 4 monogenetic cinder cones, and a random cone building event may not be out of the question.

I do try not to speculate, as many other bloggers have done, in the name of good journalism and science, but the trend is starting to look very convincing.

Image from Google Earth with USGS overlay detailing the location, magnitude, and depth of the most recent quake. 

If this does turn out to be an eruption (keep in mind, if this is magma, it still has around a mile or so to go before it breaches the surface), it would be the first in California in nearly a century. The last eruption of any kind occurred at the Lassen Volcanic Complex in Northern California in 1915, when one of the Sierra Nevada range volcanoes entered into a two year long eruptive cycle. To my knowledge, that is the only eruption in California you can actually find (black and white) pictures for.

This could easily turn out to be nothing, and the area is so remote, people would not be in harm's way whatsoever. If anything, this might turn out to be a nice tourist attraction for thrill seekers, much like the tourist who flew to Iceland during the April 2010 eruption of Eyjafjallajokull (I'm too lazy right now for the umlauts, sorry Nords!). This would be pretty great for California, as my home state depends heavily on tourism for a lot of its revenue. However, wishful thinking does not an eruption make, and only time will tell.

 *****UPDATE 2/15/2012*****

A 2.3 magnitude quake occurred today at a depth of only 3.8KM (*2.36 mi) indicating a strong, and rising source of seismicity. If more quakes occur in the same location at even shallower depths, I would start thinking that this is definitely volcanic related activity.

*****UPDATE 2/24/2012*****

Another round of tremors hit the same region today, this time at a LOWER depth of 8.0 km (down from 5.0). Three quakes ranging from mag 1.7-2.1 occurred within a 24 hour period in the same location as the previous quakes.

Large Earthquake Swarm at Reyjanes Ridge, Iceland

A large and long duration earthquake swarm hit the Reykjanes ridge of the SW coast of Iceland today, and is ongoing. The largest events were slightly above 3.0 magnitude, with many smaller events. The Reykjanes Ridge is part of the underwater seafloor spreading system that occurs between the North American plate, and the European plate, and is prone to frequent submarine eruptions and seismicity. It is unclear at this time from reading bad Icelandic translations from Ruv.is whether they are saying this is an eruption, or simple seismicity (I suspect the translated word "eruption" is misplaced in this article, and might mean "swarm", but as I do not speak the language, that's a guess!).

Tremor Graph from Reyjanes Ridge. Image copyright Iceland Meteorological Office.

Locations of the earthquake swarm (SW). Image copyright Iceland Meteorological Office.

Judging from the placement, location, and size of these quakes, it could be reasonable to assume that an underwater eruption might be occurring, however the depths, weather, and other factors could easily prevent direct observation, and volcanologists would have to infer an eruption from instrument readings (which can sometimes lie). At this point, nothing has been confirmed nor denied.

The GVP characterizes this area as such:

"The submarine Reykjaneshryggur volcanic system off the SW tip of Iceland is part of the Mid-Atlantic Ridge, which is exposed subaerially in Iceland. Numerous submarine eruptions at Reykjaneshryggur dating back to the 12th century have been observed during historical time, some of which have formed ephemeral islands. Basaltic rocks of probable Holocene age have been recovered during dredging operations, and tephra deposits from earlier Holocene eruptions are preserved on the nearby Reykjanes Peninsula."

There are no volcanoes on the Reykjanes ridge that have breached the sea surface in historical time. There is a small 'chunk' of an island along the ridge that was formerly (most likely) a volcanic feature that has since been eroded to a steep walled 'plug', named Eldey, which has the sad distinction of being the last known location of the 'great auk', a penguin-like bird that was hunted to extinction, and the last known living specimens strangled and their eggs squashed by careless hunters. The Wikipedia article on this bird is particularly sad.

I will keep my eyes peeled on the Reykjanes ridge for the time being, and post updates if anything new develops.

Tremors at Eyjafjallajökull and Katla (Iceland) Today

Several small quakes struck Eyjafjallajökull today, as the seismic swarm continued at Katla caldera in Iceland. Two small flank tremors and one at the summit hit Eyjafjallajökull within the last 12 hours. Numerous other small tremors have also continued under the Mýrdalsjökull glacier capping Katla's caldera system. Several volcano moitoring scientists, agencies, and bloggers have noted the unrest under Katla, and suspect that minor dike intrusion is occurring under the volcano.

The quakes and tremors under Eyjafjallajökull are small, but four have occurred within the last 12 hours. Numerous tremors can be seen under Katla. None of these quakes exceed magnitude 3.0.

In the case of Eyjafjallajökull, it is entirely possible these are not volcanic quakes, rather they could be structural adjustments to the volcano due to it having had a recent eruption (April 2010), and further settling of the volcano on the crust. GPS deformation charts are not available to look at at this time, so it is unclear if inflation or deflation is occurring. Looking at the Iceland Met Office website, all GPS data looks flat on all sites, so their equipment may not be functional at this time (I blame the weather). It will be interesting to keep an eye on, nonetheless.

Eyjafjallajökull caused havoc for air travel to and from Europe during its eruption that began in April of 2010. It was a fascinating eruption to watch, as it started out with a somewhat benign and beautiful fissure eruption on its NE flank (in an area known as Fimmvörðuháls) between the main summits of Eyjafjallajökull and Katla. This eruption lasted around a month, and became quite a tourist attraction, with a great webcam view for a time. After the cone ceased to erupt, there was a short lull in activity from the volcano, before it erupted suddenly and powerfully from its main summit caldera. The eruption was actually rather minor for an Iceland volcano, but due to prevailing winds, and the latitude of the eruption, Europe and Europe's airspace was choked with ash.

This resulted in a months long ban from air travel, while Europe and other parts of the world bemoaned Eyjafjallajökull and the severe inconvenience it brought upon them. Celebrities were stranded, industries were paralyzed, and in the end, Eyjafjallajökull caused billions of dollars to be lost due to economic damage.

Iceland volcanoes have a violent history. Some of its eruptions have been devastating on a global scale, especially the famed Laki fissure eruption that covered a large part of Iceland in volcanic basalt lava, and unleashed incredible amounts of sulphur dioxide into Earth atmosphere for years. This caused a worldwide famine, global cool down, and some say it was actually responsible for sparking the French Revolution! And eruptions from Hekla are famed for the terror they caused to ancient Vikings, who referred to it as "The doorway to Hell".

This has made any news about Iceland volcanoes hot topics for tabloid news, and the usual rabble like Fox or the BBC/Daily Mail. Eyjafjallajökull is NOT currently erupting, nor is it expected to again any time soon. However, volcanoes do have a habit of reminding us that they cannot be predicted in the first place, so vigilance is important with volcanoes, especially the ones that have erupted in historical time. So to be clear, there are NO eruptions currently going on in Iceland, and nothing is imminent. It looks like Katla might be reloading, as well as Grímsvötn (American name). But neither has erupted yet this year.

Possible Dike Intrusion at Golden Trout Creek

A minor earthquake swarm is ongoing south of the main peak of Golden Trout Creek volcanic field in CA, USA. The largest event so far has been a mag 2.9 tremblor (curiously with a depth of 0.0 KM), with aftershocks or other independent quakes registering from 1.1-2.3 magnitude. Due to the locations and magnitude of the quakes, this could be related to minor dike intrusion. If it is, there can be an expected die-off of indigenous trees in the area due to CO2/SO2 release similar to what happened at Mammoth Mountain in the 1990's.

This area does not produce frequent earthquakes.

The quakes have been recorded in a longitudinally linear fashion, with most occurring at or near the same depths, indicating a localized source, with the exception of the 2.9 tremblor at surface depth, which could be depth read error. This area is not highly known for much tectonic volcanism.

The Golden Trout Creek volcanic field is a Holocene volcanic center, listed on the GVP as an active volcano. While no historical eruptions have been recorded at Golden Trout Creek, the last eruption has been carbon dated to be around 5-10,000 years old, post dating glaciation at the site. In short, this volcano has erupted when humans were present on North America, and probably will again.

This current cycle will NOT likely result in any eruptive activity, however, as with all active, or slightly active Holocene volcanoes, there is always that possibility.

The Golden Trout Creek volcanic system is not near any large population centers in California. If it did erupt, it is likely that news would be slow to come out of that area, if at all. The area is known for producing about 5 different volcanic cinder cones, which are monogenetic (erupting only once) in nature. The last volcanic eruption produced a ~6km flow down a river gully.

The below picture is from Google Earth with the USGS overlay added, and the largest earthquake highlighted.

 

5.2 Mag Earthquake Strikes Near Santorini, Greece

A 5.2 magnitude quake struck approximately 30 miles Southwest of Santorini Island today at 4:42 UTC. The quake was followed by 4.1 and 4.2 aftershocks. 

Image from Google Earth with USGS overlay.

Santorini volcano was last active in the 1956 when a large earthquake and subsequent volcanic eruption resulted in the demolition of buildings and evacuations. An island was formed in the middle of the caldera, and thermal activity still occurs. While these quakes are not near the magma chamber, they do have the potential of destabilizing the region. More than likely a few aftershocks will continue to be recorded in the quake area.

*****UPDATE 1/27/2012*****

Another earthquake registering mag 5.2 has hit the same area, slightly SW of the original quake. This seems to confirm a statement from Greece's geologists that the Santorini fault is now in motion, and we could expect more quakes. Whether or not the quake activity affects nearby Santorini/Thera volcano remains to be seen, but scientists are being very cautious at this point in regards to statements. They are however closely monitoring the situation. Likely this will cause more fault slips and afterschocks. It will be interesting to see if there is a cascade effect up the fault to Santorini, but at this time it appears the activity may be moving away from the caldera. I will post more updates if anything new occurs.

*****UPDATE 2 1/27/2012*****

A 4.7 aftershock has hit near the epicenter of the first 5.2 quake.

3.8 Magnitude Quake in Clear Lake/Geysers California

A magnitude 3.8 quake hit Clear Lake today at around 4:30am north of the normal seismic swarm region. Typically, the Clear Lake geothermal prospect can cause up to 50 small quakes a day, many ranging from 1.0-4.0. 3.8 is a bit larger than the area usually sees, and this quake is different due to its location and size. The area where this quake occurred is at the SE shore of the lake, not near any geothermal drilling or activity. This is most likely a tectonic event and not magma movement, although the area is considered to be an active volcano.

Above image from Google Earth with real-time USGS layer added.

Waveforms of the quake from USGS website.

The Geysers Geothermal Field/Clear Lake area has had an ongoing quake swarm since geothermal power plants were installed on the mountain range south of the lake. This has been going on since the late 1990's. While information on this activity is hard to come by, and the science papers released mostly being from corporate scientists with interests to protect, it is anyone's guess what's going on in this area. The wave forms do appear to be tectonic from this quake (above), so it's probably not a cause for concern. As always though, I will keep my eyes peeled on this location to see if anything new develops (but I'm not going to lose any sleep over it).

Activity Strong Today At El Hierro

The Canary Islands volcano does not seem to want to quit. Despite reports around the web and other blogs that say "El Hierro Eruption Stops", it seems again that El Hierro is making fools out of those who try to predict this volcano. Today the activity is quite high, with more lava balloons (gas filled lava that floats on the surface of the water) visible day and night, and a very strong "jaccuzzi" area present during the afternoon at El Hierro (below).

Picture from Movistar/Telefonica webcam.

El Hierro has been in a sort of on-off-on-off-on pattern with its eruptions, probably due to structural adjustments and dome collapse underwater. Once magma pressure builds again, activity resumes. This is probably indicative of a large magma chamber beneath the island. My guess is that the volcano probably has plenty of life in it yet, and that we can't expect it to stop anytime soon.

Pictures posted on Earthquake-report.com from the local scientific expeditions show that there are now two vents active underneath the water. The main vent, lovingly referred to as "Bob", and a nameless vent closer to the shore, but much smaller. The dual jaccuzzis can be seen in the image above. 

The main vent is now a mere 30-50 meters below the sea surface, and if activity continues, we will most likely bare witness to a surtseyan eruption within a couple months. Just last month a similar eruption created a new island in the Jebel Zubair chain in Yemen. Since that area isn't closely watched, and is rather deserted, that eruption was a surprise only identified by local reports and satellites. Scientists did not witness the start of the eruption underwater, and thus only knew of the eruption once it breached the surface, so we have no way of knowing how long Jebel Zubair erupted for. 

We are fortunate with El Hierro to see the precursors to the eruption in the form of a vast amount of earthquakes, along with the underwater cone building phase, and hopefully the surtseyan island forming phase. This will have been a complete record of an eruption, and will no doubt be invaluable to science.

6.2 Mag Quake Strikes Chile Near Bio-Bio

A 6.2 magnitude earthquake struck today near Bio-Bio in Chile, off the coast. No tsunami warning was issued (at least according to the few reports I read). The quake was at a depth of 29.7KM, and was followed by a 4.9 aftershock. The town of Tome' was the hardest hit, with shaking in the area characterized as strong-very strong on the USGS scale. The quake was felt further inland.

Chile is prone to frequent earthquakes and volcanic eruptions, and resides entirely on the rim of the Pacific Ring of Fire, the tectonic plate boundary where the majority of Earth's active volcanoes are located.

Chile has seen some very strong quakes in recent years, with an 8.8, and 9.0 striking last year alone. The 9.0 quake did cause a tsunami, that resulted in only one fatality (a guy from my hometown no less!) where a man was taking pictures of the wave at his own risk, and got swept up the West Coast from California and ended up in Oregon. Some damage was caused by the tsunami in various ports where boats got knocked together, and a minor wave also 'hit' Hawaii, although this caused little damage as well.

There is no word yet on whether or not the current quake caused any damage or injuries. 

Chile's Lascar Volcano Alert Level Raised

The Smithsonian GVP and Chilean media report that Lascar volcano has been raised a level on their alert scale due to increasing seismicity and volcanic tremor. There is a great article on Wired.com that details the latest unrest and provides plenty of great links to other info and a webcam for you volcano-voyeurs.

Lascar Volcano is one of Chile's most active volcanoes. Situated amongst many other young and old stratovolcanoes in the Andes range, many of them also considered to be active, it has produced some very large eruptions in our recent history, the largest of which occurred in 1993 when pyroclastic flows traveled more than 8KM from the summit, and ash fell as far away as Buenos Aires. Current activity would likely consist of explosive eruptions, although probably not as large as the 1993 event.

The volcano is located about 70KM southwest of the town of San Pedro de Atacama. The volcano, due to its remoteness, is not considered a threat to anyone, or anything (except perhaps aircraft due to ash), and is not close (within 20 miles or so) to any population centers.

You can read the article on Wired.com for yourself, and enjoy going down the rabbit holes (links). Its always fun to get to really know a volcano!

Sierraville, CA Quake Swarm Returns

A quake swarm has again occurred (and is possibly ongoing) under Sierraville, CA at approximately the same depth as the previous quake swarm. The previous swarm was determined to be minor magma dike intrusion, which is also likely the case here. There is still no risk of a volcanic eruption, the intrusion is taking place at around 30-40KM beneath the surface, so it is still quite far.

The Sierraville swarm is an interesting one to watch. The area does not have any recent eruptive history, however hot springs and fumeroles can be found near the area.

The current continuation of the quake swarm occurred between December 29th, and January 3rd. Two quakes of mag 1.4 and 1.2 occurred today at a depth of 33KM.
                            

The Sierraville swarm has been felt by residents unaccustomed to frequent quakes. Given the fact that we know these quakes are volcanic intrusions, I'm sure the residents may be a bit nervous. But this swarm will likely never result in an eruption due to its depth. Indeed many magma dike intrusions never result in a surface eruption. It does not mean it's impossible, but I'd try your luck at the lottery first if I were a betting man.

Anyhow, something interesting to watch.

New Volcanic Monitoring Tech Under Development

Scientists are close to deploying en masse a new technology that could greatly improve our knowledge about the inner workings of volcanoes, possibly leading to a method in the future to determine how, when, and for how long an eruption might occur. Last night on PBS (here in the States), Nova produced an excellent show about volcanoes and what is being invented to monitor them properly. This is a two fold solution to a problem that has vexed mankind since our earliest days on the planet.

First, there are many technologies that can 'map' a volcanoes inner workings. The most common is seismic monitoring through low-velocity zones. What happens here is that deep earthquakes around a volcano (such as Yellowstone) are recorded by multiple instruments around the area. The data is timed so that computers can analyze exactly how fast, and at what portions, the waveforms slow down, or travel unimpeded through the crust. A slower wave form denotes molten, or semi-molten rock. This is called a low-velocity zone, and computers can now produce rather accurate images of underground magma chambers, which was recently done to Yellowstone.

But a far greater technology is in the works, and one that will not require thousands of seismic recorders, and is independent of earthquake data. Cosmic rays have been observed to produce particles called muons. Muons travel at near light speed, can easily travel through objects such as mountains, buildings... us. Scientists have figured out a way to place muon sensors around a volcanic summit to not only map the inner magma tube that feeds volcanic summits, but can tell where the magma is, at what pressure, and produce a very detailed 3D image of the inside 'guts' of a volcano.

This technology coupled with seismic extrapolation of underground magma reservoirs will GREATLY reduce inaccuracies in predicting or assessing eruption risks. This technology is now currently being used on Italy's Mount Vesuvius, which most scientists agree is currently the worlds most potentially lethal volcano, with a large population (in the millions) living around its base. Vesuvius is most famous for the 79AD eruption that destroyed the town of Pompeii, but it has had many many eruptions in the last 2000 years. It erupted during WWII, and again in the 1960's in recent history, but has since been oddly quiet.

The second volcano to be monitored is another potential killer. Mount Shasta on the West Coast of the US is a silent monster, looming over the Washington state skyline like an American Mt. Fuji, it is structurally weak, and has a record of historical activity. The main threat from this volcano is flank collapse that would result in landslides and lahars, however elevated thermal temperatures and chemicals in surrounding creeks suggest that the volcano is also slowly heating up. Nova pointed out that the eruption of Mt. St. Helens in 1980 was preceded by reports of discolored and high temperature river water weeks and months before the actual eruption. This has prompted the muon analyzing tech to be deployed around Shasta to get the real story on what's going on.

In any case, the technology for volcanic monitoring and prediction is improving by leaps and bounds as technology improves day by day. It is entirely possible that with these combinations of technology that getting caught off guard by a volcano erupting may soon be a thing of the past... at least for countries that can afford the investment. Areas that are remote, and inconsequential to humans, like the Aleutian Island volcanoes of Alaska, would probably be a low priority area for deploying this technology. However urban centers near these volcanoes would certainly benefit.

If you weren't able to see this Nova presentation last night, I'd see if you can find it online, or maybe order it from PBS. It was a great special, and brings a lot of food for thought.

Sierra, CA Earthquake Swarm Resumes

Sierra CA has experienced another minor swarm of earthquakes in the same region as the previous swarm. The previous swarm was determined to be magma dike intrusion by geologists, although the intrusion is at a fairly deep depth and has very little if no chance of breaching the surface.

The below screenshot from Google Earth with the USGS KML file enabled details the locations of the quakes. They all occur at a depth of approximately 30KM or deeper.

                                  

The Sierra swarm is of little consequence to the community aside from the periodic shakes, however if the quakes do become shallower, they will be felt more strongly. There is very little chance of a new volcano or vent opening up (but as always, it is not impossible). While this event series is NOT tectonic in nature, the depth at which it is occurring does nto signal a volcanic eruption.

There are to my knowledge, very few news agencies reporting on this, so don't hope to find anyone else on the 'net!

Mono Lake Earthquake Swarm Ends

There has been no renewed activity at Mono Lake since the last post. The swarm at this time appears to be over. If the area does have some more earthquakes, they will likely be small and shallow (~5km) and become less frequent. This could have been magma dike intrusion, or even cryptodome intrusion, as the area does have a history of that. However given the seismographs I've reviewed in comparison to past tectonic events, this event was likely purely tectonic/structural and will likely not result in any eruptive activity.

Mono Lake has not had an explosive eruptive event in human history, but has a rather unique geological past. The last activity to occur in the area resulted int he intrusion of a rhyolitic cryptodome, which in turn created some hydrothermal activity resulting in the extrusion of the famed tufa towers. The lake has since been of particular interest to astrobiologists (those that study the biology of potentially extraterrestrial life forms) due to the presence of bacteria that thrive on the element arsenic.

The area is an extension (as some claim) of the Long Valley Caldera, a dormant supervolcano (similar to Yellowstone) that has experienced long periods of uplift and subsidence since the 1970's. Long Valley Caldera is monitored by the USGS at the Long Valley Observatory (http://volcanoes.usgs.gov/lvo/) but the observatory does not often keep up to date with Mono Lake.