Unlike stratovolcanoes, shield volcanoes never are visually impressive except for their sheer extent as shown in this photo of Medicine Lake Volcano (Julie Donnelly-Nolan)
A repost from 2016, written by Henrik and part of our series on volcanoes of the American west. There is enough there to make any nation proud! This follows on from the post on Mount Shasta and on Tehama.
The more you read about volcanism in North America, the more confused you become by the immense complexity of eruptive phenomenae and sequences. As will be clear from my previous article about Mount Tehama (Lassen), it is not always a question about a single central volcano such as Vesuvius or Etna, but about a multitude of volcanic vents and events tied to an area.
Just 50 km (30 miles) northeast of Mount Shasta lies the largest volcano of the entire Cascadia arc, the half-a-million years old Medicine Lake Volcano and on its Northeast flank, the associated Lava Beds National Monument. The Medicine Lake Volcano and the Lava Beds National monument is a great example of how complex and varied volcanism in the Cascades Arc is. That the volcano itself, despite being the largest volume-wise in the USA, does not have a proper name but is named after the lake inside its summit caldera is another example of how shield volcanoes are often overlooked.
Medicine Lake Volcano is a shield volcano that in main has erupted dry HAOT (high-alumina olivine tholeiite) and hydrous calcalkaline basalts simultaneously, but also some andesitic magma. It rises about 1,200 m (3,900 ft) above the Modoc Plateau and under the centre of the volcano, the underlying rock has been pushed down by 0.5 km (0.3 miles). On average, the shield is only about 1 km (0.6 miles) thick, but as the extent of the shield is a massive 35 km (22 miles) east to west by 45 to 50 km (28 to 31 miles) north to south, it covers more than 2,000 km2 (770 square miles). The total volume is estimated to be in excess of 600 km3 (140 cu miles), which makes Medicine Lake Volcano almost twice the size of Mount Shasta.
Unlike most other South Cascade volcanoes where a shield has first been deposited before one or more stratovolcanic cones were built on top, there has been no such development at Medicine Lake Volcano. It is believed that the Medicine Lake Volcano is “unique”, having many small magma chambers rather than one large one. Regular readers of this blog will recognise this line of reasoning as many volcanoes are believed to have a magma reservoir consisting of a system of chambers, sills and dykes rather than a single, large magma chamber and that such a magma reservoir may develop from sills and dykes into one or more larger magma chambers.
Medicine Lake, the collapse caldera structure at the summit of Medicine Lake Volcano with Mount Shasta 50 km away in the background. (kitezombies.com)
On top of the volcano lies Medicine Lake, a 7 by 12 km (4.3 by 7.5 miles) caldera structure that is thought to be the result of collapse after a large volume of andesite erupted from vents along the caldera rim. Also, there is a system of ring fractures associated with these vents, it is thought that they were there prior to the caldera collapse. As the only eruption to have produced an ash flow tuff occurred in late Pleistocene time (~200 to ~180 ka), and this eruption was too small to account for formation of the caldera, it is thought that the caldera may have formed in a similar manner to that of Kilauea.
Eruptive activity during the Holocene has been episodic and includes numerous rhyolite and dacite lava flows from vents at high elevations inside and outside the caldera. Eruptions at vents on the flanks of the shield have resulted in cinder cones and associated lava flows of basalt and basaltic andesite. Most vents are aligned along lines of crustal weakness that trend North East to North West. About 10,500 years ago, eight eruptions within a time interval of a few hundred years produced about 5.3 km3 (1.3 cu miles) of basaltic lava. After a period of dormancy of about 6,000 years, there was a small andesitic eruption about 4,300 years ago. The most recent eruptive episode lasted between 3000 and 900 years BP, when another eight eruptions produced approximately 2.5 km3 (0.6 cu miles) of lava ranging in composition from basalt to rhyolite. While the late Holocene lava compositions include basalt and andesite, silicic lavas ranging from dacite to rhyolite dominate.
Glass Mountain, a rhyodacitic obsidian flow and most recent activity at Medicine Lake Volcano. (rhysw.com)
The most recent eruptive episode at Medicine Lake Volcano occurred around 1,000 years ago when rhyolite and dacite magmas erupted at vents near the caldera’s eastern rim and led to the formation of Glass Mountain and ten smaller domes. Glass Mountain consists of a steep-sided rhyolite and dacite obsidian flow that erupted just outside the eastern caldera rim and flowed down the steep eastern flank of Medicine Lake Volcano. The tephra pumice deposits that preceded the flow have been dated to less than about 1050 years before present while radiocarbon dating of a cedar tree indicate an age of about 885+/-40 years BP.
Recent exploratory geothermal drilling has identified a surprisingly silicic core mantled by mafic lavas. This result is unexpected and very different from the long-held view derived from previous mapping of exposed geology that MLV is a dominantly basaltic shield volcano. It was found that while < 6% of the ~2000 km2 of the mapped Medicine Lake Volcano lavas are rhyolitic and dacitic, drill holes on the edifice penetrated more than 30% silicic lava. It seems as if the andesite – dacite lavas that built most of the nearby Cascade stratovolcanoes never did erupt to form the usual stratovolcanic edifice on top of a basaltic shield at Medicine Lake. Since Medicine Lake Volcano is still an active volcano, even if presently dormant or between eruptive episodes, future large silicic and probably effusive eruptions are likely.
Illuminated lava tube cave. (wikimedia commons)
The Lava Beds National Monument covers some 190 km2 (74 sq miles) to the northeast of Medicine Lake Volcano. It has one of the World’s greatest collection of different volcanic features such as lava tubes, cinder cones, spatter cones, hornitos, pit craters, maars, fumaroles, lava flows and volcanic fields. Most of the lava tube caves were formed by basaltic lava flows dated to about 30,000-40,000 years ago. 90% of the lava flows are basaltic and of those the smooth, easy-flowing and ropy Pahoehoe are the most common. The remainder of the lava flows are andesitic in nature. The park is also home to numerous cinder and spatter cones ranging in age from 114,000 to 3,025 years. The lava fields range in age from the two million years of Gillem Bluff to just under 1,000 years of the flow that created Glass Mountain.
The petroglyphs, Native American rock carvings at Petroglyph point (WikiMedia Commons)
One of the most intriguing features of the Monument is Petroglyph Point which formed about 275,000 years ago when cinder erupted through the shallow water of Tule Lake and violent explosions of ash and steam formed layers upon layers of tuff. Petroglyph Point is named for the Native American rock carvings, one of the most extensive in North America. Another interesting feature of the park is Captain Jack’s Stronghold, a natural fortress of lava tubes named after Captain Jack, a Native American who led a group of 53 fighting men and their families of the Modoc tribe that held off US Army forces for five months in spite of being outnumbered ten to one in the Modoc War of 1872-3.
(At the time of writing (2016), most sites containing information were shut down on the order of the President of the USA and only allowed to announce the fact while denying access to all information. Most regrettably, to say the least, the petroglyphs had been vandalised which has led to access to Petroglyph Point being denied.)
Henrik
My favorite US volcano is Vulcan’s Throne, which erupted so close to the edge of the Grand Canyon that lava flowed down into it. I’ve always been interested that it didn’t take the shorter course and go sideways into the canyon directly.
Thanks in peace Henrik!
Why was the Medicine Lake Volcano baptized Medicine Lake Volcano? Was there a Medicine man or a native American cure for a disease?
The name Medicine Lake derives from the fact that local tribes held rites at the lake. The name was in use already in the 19th century
Cf. also “Medicine Line”.
Readers might like to read this small report from the USGS https://www.usgs.gov/volcanoes/medicine-lake/science/hazards-summary-medicine-lake as it has a nice map of past activity.
It resembles a bit Taal, but without an island in the lake and without an island carrying the caldera. Many locations for eruptions are possible and many different types of eruptions.
Klyuchevskoy finally calming down after six days of continuous ash emissions above 30,000ft. Must be its largest eruption in a long time, VEI 3?
The one in Oct 2023 was almost an intense and maybe somewhat longer (looking at MIROVA), but overall this one was probably larger.
Here’s a very interesting paper that purports a very high correlation between solar activity/solar storms and earthquakes due to electrical currents within the earth’s crust that can heat a fault.
Note though that fault heating from reverse piezoelectric effect-induced currents, though plausible, would be just like the straw that broke the camel’s back. The quakes following the solar storm would need to be right on the brink of failure anyway, so it’s not like the storm created the earthquake.
What I find interesting though, is the apparent 1 day latency between peak currents and the eventual failure of the fault. That implies there must be some sort of “activity” going on in the time period between the the quake and the electrical heating maximum. Too bad that despite massive attempts (like Parkfied) we have yet to detect what that pre-quake activity might be. One possibility is the fault/crystal is first heated, then cooled and it’s during the cooling stage that the crystal cracks from thermal shock that leads to complete fault failure…not unlike hot glass getting fractured as it rapidly cooled. If we do figure out how to measure/detect what is happening, it would be a holy grail for earthquake prediction.
https://www.nature.com/articles/s41598-020-67860-3
Note that this paper is an old one…dating back to 2020, so it’s not news…but in light of the recent widespread uptick in activity that hit the Aleutians and Kamchatka in the last month or so, is a bit curious.
That fails my initial ‘sniff test’ – the lead author is described as an ‘independent researcher’ and has only published a handful of papers, on two subjects: earthquakes, and covid!
My bogometer is pinging at this point.
Kilauea’s south flank had a relatively high number of quakes recently. Is there a risk for a large tectonic event?
The large tectonic event was in 2018 its still moving from that. Mag 5 might happen, even a 6 if magma starts pushing into the rift and stays going that way for a while. But a 7 or close is something decades apart. Mauna Loa might be more likely, if its next eruption goes southwest or far east, though I havent seen much evidence Mauna Loa is close to erupting again yet.
While aftershocks from the M8.8 continue to slowly subside, a new wrinkle in the pattern has emerged. which is a couple of deep/ultra deep-focus earthquakes under the Sea of Okhotsk. So far these are only minor shocks…but their location immediately downrift of the main slip zone and extreme depth is suggesting stress has been added along the entire width of the fault to 525km.
Deep-focus earthquakes in this area are known to happen, with an M8.3 event as recently as 2013. That shock was well west of the northern tip of the M8.8 aftershock zone, with not as much activity south. Not sure if this apparent seismic gap at the tip of the subducting Pacific Plate under the SoO and running parallel to the Kamchatka Trench is due to the fault being locked or the crust is too malleable to support much stress buildup i.e. a pseudo creep pattern?
Will be interesting to see if there are any more DF EQ’s in the near future.
https://earthquake.usgs.gov/earthquakes/tectonic/images/kuril_tsum.pdf
https://earthquake.usgs.gov/earthquakes/map/?extent=45.05801,-219.06884&extent=58.66552,-186.26367&range=week&listOnlyShown=true&showUSFaults=true&baseLayer=ocean&timeZone=utc&settings=true
https://www.universetoday.com/articles/the-jwst-found-evidence-of-an-exo-gas-giant-around-alpha-centauri-our-closest-sun-like-neighbour
Not totally certain yet, but Alpha Centauri A probably has a saturn sized planet orbiting about 2.5 AU, slightly further than Mars but well within its habitable zone. Its no doubt such a planet has moons, which would be potentially habitable. Although, a moon the size of Earth would be very big compared to the planet, only our own moon has a less than 100:1 ratio of mass compared to the parent and is suspected to have unusual formation circumstances.
Also, Alpha B would be very bright, but not hot. From the planet, there would be a significant part of the orbit that there would be no true dark of night, as the other star would probably keep the sky a twilight brightness. I dont know if it would be bright enough to be dangerous to look at.
But still,
Actually, Mars is only 1.5 AU, so Alpha Centauri Ab would be in the asteroid belt if placed in the solar system. Apparently the orbit might be pretty eccentric, but hasnt been confirmed. Alpha Centauri A is 50% brighter than the Sun but at 2.5 AU it would only be about 60% as bright as the Sun looks on Earth, so more than Mars (43%) but not much, and probably pretty cold though not anything like our own gas giants either.
Alpha Centauri B is half the brightness of the Sun, and closest it ever gets to the planet is still 8 AU or more. So it would be about as bright as the Sun at 16 AU, or where Uranus is, and 1/400 of what it does on Earth, and at its max distance of over 36 AU it would be the same as looking at the sun from 72 AU, where it is 1/5000 as bright. So about as bright as on Sedna, and a lot dimmer than the Sun looks at Pluto. But still 80x brighter than a full moon, so the sky wouldnt really be dark.
So basically any serious astronomical observation of the sky would only be possible when both stars can be eclipsed by the planet, and for most of the planets year the sky would never be completely dark. Only possibly close to the polar circles on Earth are comparable conditions met but still very different.
Any life on one of the moons would have a very different circadian rhythm, if even possible, and might well favor either extremely short or extremely long lived aliens, to avoid the slow but significant change a roughly human lifetime would show. Avatar having seemingly normal day night is inaccurate, or at least means it was very specific in the location in orbit. Although, having the life be so vividly bioluminescent might also be a consequence of having no true night most of the time, visual information being very important, and thus selected. Even if bioluminescence is often seen in opposite conditions on Earth.
The purported planet has an average distance to alpha Cen A of 1.5-2 au, but in an elliptical and quite unstable orbit with large fluctuations in ellipticity and orientation. Although in the habitable zone, it would not meet conditions to be considered habitable and that would also be true for any moon.
I am not fully convinced by the finding. They saw the planet once but two follow-up observations to confirm the object did not show it. They claim that the orbit of the planet put it too close to the star to be seen at either of those times. We also have limits on possible planets from velocity measurements, and the finding here are only just compatible with those (that is in fact where the reported mass many comes from). And finally, although they claim that the orbit would be stable over a million years, in view of the large fluctuations of the parameters over time, I expect it would eventually be flung out. Wait and see whether it is detected again – until that time, this planet remains unconfirmed.
Problem is, it will take years to confirm it, requiring 2-3 years per orbit and probably at least two full orbits to be certain. If it is real, the orbital data will probably resolve to be much less unstable, as it wouldnt be there otherwise in a star as old as Alpha Centauri, even older than the Sun by 500 million years. More stable doesnt necessarily mean less eccentric, though.
Its still a good example of how inefficient the transit method really is. Its simple and reliable, but only a few percent of planets are visible. And none of the methods are very good at seeing any planet with an orbit of less than about 15 years, or small planets. Hence why hot Jupiters dominate early exoplanet discovery despite being pretty rare. And probably also why we apparently think super Earths and mini Neptunes are more common than planets the size of the Moon or Mars, easier to see.
Its also very likely why an exoplanet system bigger than our own solar system hasnt been found, it would be basically impossible to completely confirm all 8 of our planets in a 30 year interval viewed at a aistance externally. Probably only Earth, Venus and maybe Jupiter would be seen quickly.
https://browser.dataspace.copernicus.eu/?zoom=15&lat=-1.40883&lng=29.20522&themeId=DEFAULT-THEME&visualizationUrl=U2FsdGVkX19CxnJNhPa33FlmIcq%2FO%2FLhIdb0r9CElhj%2BsekQRiKPcAZsw%2BE0vhQw07pbGUCBgQDt5Cf8ExPX3lLy0UbpG4%2Fu5RAuYVQEV%2FOq3WVvj1FU6JlfA8hC41Cz&datasetId=S2_L2A_CDAS&fromTime=2025-02-14T00%3A00%3A00.000Z&toTime=2025-08-14T23%3A59%3A59.999Z&layerId=6-SWIR&demSource3D=%22MAPZEN%22&cloudCoverage=30&dateMode=MOSAIC
Latest satellite from Nyiramuragira the huge lava lake is in full overflow mode, overflowing its shore sides and its still feeding internal lava tubes down the flanks this is massive thermal radiation thats likely blocked from space alot by cumulus clouds and the eruptions large condesation plumes. Its a scenario for Kilauea is well in a few years time and even more crazy with its even higher supply.
https://www.youtube.com/watch?v=eDnIssGti0I current lava lake sizes, once Kilauea gets a rift vent and the summit collpases into the chamber like it did in 2008 then it maybe very well able to beat Nyamuragira in size of lava lakes simply due to Kilaueas huge supply and massive magma chambers indeed the 2018 overlook lava lake where still growing before it was destroyed
I think some sizes are wrong, though. No way Yasur has a 150 m lava lake and Masaya doesn’t even have one anymore, unless it hidden in an overhang or something, but the sat shows nothing..
Coud be the thermal radiation bleed in space imagery that he missreads…
Nyamuragira’s lava lake is insane. The image below shows the same Sentinel band visualization of Nyamuragira current lake (left) and Nyiragongo’s pre-2021 lake (right). Nyamuragira’s is not only bigger than the old lakes of Kilauea and Nyiragongo but its surface is much hotter, and the southern corner seems to be churning as violently as Ambrym’s lakes whenever the satellite gets a view through the clouds. The lava lake is covered in clouds most of the time, but it’s likely radiating 2,000,000,000-3,000,000,000 Watts of heat all the time, judging from the MIROVA emissions reported from time to time..
Just the radiated heat alone of Nyramuragira’s lake should be more than enough to power a city of 1 million people in an industrialized country, according to Google AI’s estimate on how much a city would consume…
Does that compare to heat energy required for the city or electricity? There is a factor of about 3 difference between them
I’m not really sure, but as an orientative figure I hope it’s accurate enough.
Yes, that is a difference (for green energy) everyone chooses to overlook.
Doing otherwise would be too much of a challenge. “They” wouldn’t be able to do enough and “WE” might have to forgo things, perish the thought.
You can recover the difference with a heat pump – but only for applications using moderate heat.
Farmeroz every square km gets 1 GW of solar irradiance at peak too, and we capture about 1/4 of that in panels for electricity, but heat could be near 100% using the right setup. Burning stuff is totally unnecessary.
Also, the average house in the UK is apparently about 75 m2, and even in winter this would generate about 40 kW of heat, which is way more than required to heat a home. Most other places in the world have more. Paint the roof black and use it to heat something up, free geating no burning required. Or heat pumps, which are 300% efficient at heating a room vs the power draw they demand.
I wont even go into how every diesel car probably uses more electricity indirectly than a similar EV to go an equal distance… Not equivalent efficiency in the fuel but actual electricity used to refine the fuel that could have been used to charge an EV or similar instead. The grid problem would basically be solved just by not making fuel…
Its BS that we need fossil fuels for anything, we never have, we just scaled the tech quickly and most people dont care. At this point is just money and scale.
Heat is hard to keep or transport. You also forget about the angle of the Sun. In midwinter, your UK house will generate 13 kW of heat at peak, assuming clear weather. (We occasionally have that in winter.) The average UK house uses around 100 kWh/day during winter. So no, your heat panels won’t get anywhere near that. Of course, we could improve insulation, but people in the UK appear to enjoy outside air in their homes.
Numbers I saw were 600w at directly above in winter Albert, which I rounded a bit. I assume that doesnt include weather but fossil fuels are equally as variable. Even if insufficient it is still a very large portion in the worst case and
Also, 100kWh a day is almost unbelievably bad efficiency, or people there are very lazy with heat. My old house that I got the bill for directly (not the case presently) used 9 kWh in summer and 14 kWh winter, daily, of electricity, so roughly 30 kWh of heat going on the ratio you brought up, though all our heating was ultimately electric so this is very likely a significant overestimate. And the house much bigger than 70 m2. Granted also under 10 years old but still.
UK is also much less sunny than the rest of Europe, and basically everywhere else people live. And other places as far north are much more renewables heavy and independant already. Its a worst case scebario and still works out most of the time. Energy storage and insulation would go a long way if the numbers above are true…
That 600 W is presumably peak power per square meter, but it needs to be multiplied by the sine of the angle of the Sun above the horizon which in mid winter can be 10-20 degrees at mid-day. It is also possible that you quote to the total generated for 1m2 of roof over one a day, in which case it should be 600 Wh which would be reasonable for a good day.
The average energy used for space heating in the UK is 12000 kWh per dwelling per year. The large majority is used over the three winter months when average peak temperature is below 10C. So divide by 100 days to get the value of 100 kWh/day for heating.
The European standard for heating of a ‘passive house’ (ultra-low energy building) is 15 kWh per square meter of floor area per year. The UK has on average 130, and most European countries are similar. Portugal which has a mild ocean climate has 16 and Spain 48 – this shows the impact of milder winters. In my experience when measuring daily use, it is mainly about number of days with peak temperature above or below 10C.
Interesting, but it still shows a pretty terrible efficiency to be honest. Tasmania isnt quite so cold but is only barely over 10C in winter, and often under 5 C overnight. So probably 5C warmer than the UK. Thermal storage and insulation would be a very big help.
That, and also only heating occupied rooms.
Tasmania has a variety of climates. Hobart is considerably warmer than the UK, certainly by more than 5C
“Tasmania isnt quite so cold but is only barely over 10C in winter, and often under 5 C overnight. So probably 5C warmer than the UK”
Well for me that lives in arctic latitudes ( which UK also borders Albert is just warmed by the gulf stream) well Tasmania sounds like a Tropical paradise for me its at least very mild subtropical
I sometimes imagines Nyiramuragira growing in the the sea faults in the Baltic Sea, forming a nice 60 km long uninhabiated Island 100 kilometers north of Gotland with lava flows flowing down into the murky shallow waters. Its a nice place right between Estonia and Stockholm and you can take tourist ferrys out there and watch the volcanic activity of course something thats impossible in a Craton
Russia would claim them immediately
https://www.youtube.com/watch?v=WiPZyOuBgHY
13:17 – 14:08 Its always a stunning sight seeing the whole earths ocean boil under a superhot rock vapor atmosphere, even sillicate clouds are rendered in the hot sky. During an impact as large as this the whole ocean starts to boil in the extreme heat. Its the only good animation that shows what woud happen IF a dwarf planet hit out planet, which was a common thing during the hadean era.
It woud not take a long time to completely boil away the baltic sea in souch a hot “rock vapor photosphere” after souch a large impact, only place livable for humans is the deepest mine in Africa where the terrible heat cannot reach, you wait for decades decades for the atmosphere to completely cool and the oceans to re – condense rain back
An impact as big as this is so bad, so extreme is the atmospheric heat pulse its enough to turn all the sand in all earths deserts into seas of molten glass…imagine all the sand dunes on the planet melting into white hot seas of liquid goo…. the imaginary impactor is 50 times wider than the KT impactor for comparison here
Mostly ( ONLY ) a thing during the Hadean era luckly!
An extreme enviroment indeed is a rock vapor atmosphere, real hot clouds of iron and magnesium condensing high up in this hot post impact rock gas atmosphere, there may rain iron and lava, but that evaporate as virga before it hits the hot lower atmosphere. After many years the atmosphere thats radiating like a star starts to cool, and the rock vapor starts to condense and dissipate raining out as lava glass leaving a global layer of of melt tektites 100 s of meters thick, the oceans rains back when the atmosphere drops below 100 c
Somewhat OT: Nasa just published a nice satellite view of the Klyuchevskoy eruption:
The accompanying short article can be found here:
https://earthobservatory.nasa.gov/images/154670/ash-streams-from-klyuchevskaya-sopka
They are speculating that the big quake may have helped to trigger the bigger eruption / enhanced a previously ongoing small eruption.
A second article describes a satellite view of the tsunami that was triggered by quake:
Accompanying second article here:
https://earthobservatory.nasa.gov/images/154666/swot-spots-tsunami-wave-after-kamchatka-quake
Kilauea: SDH station is a bit faster inflating than the other three summit tiltmeters. Is the next episode going to move more towards the new southern vent?
Probably just means the supply rate into the deep main magma chamber is higher than the flow from that chamber to the one under Halemaumau, slightly. Its pretty common that they would do this, and the reverse be true at times too.
The glow is still weak at the main vents, and UWD is still about 5 microradians lower, with a recent daily rate of 1.5-2, over the 3+ earlier. If SDH is ready then it might rebound quick but E31 is probably still at least 2 days away. But E31 will.also be a large volume and its not unlikely flank vents will open again. The south fissure was probably a satellite of the existing vents not a new dike intruded up from the magma chamber so it reactivating is uncertain but possible.
Quiet lava flow on Etna’s west side. Purely effusive. https://www.youtube.com/watch?v=1qBlVJwKHd4
Drone video:
https://www.youtube.com/watch?v=Huemt54sv80
That’s an ideal tourist eruption. You can watch the lava source nearby without the risk of sudden lava bombs.
One of the new images of the Ep. 30 fissure. Note the bathtub ring where the lava drained back into the fissures once they stopped. The helicopter just puts into perspective of how big they are…
It will be interesting to read that it is independant of the main vent. Its not what is likely, but its still an option. The fact the main vent was no different to E29 despite the new fissure might indicate more than it appears.
http://www.mounts-project.com/static/data_mounts/kilauea10/2025/kilauea10_20250808T161534_20250814T161632_VV_ifg.png
New interferogram, strongbinflation but centered in the caldera more generally, though this is probably normal and just harder to see earlier.
Iceland. Trölladyngja seems to be rattling a bit, today. Low activity up to 3.1km, and probably rock cracking.
if u plot the quakes in https://skjalftalisa.vedur.is for the krisuvik area it does look like activity has picked up a lot since june compared to the previous year (unfortunately can only plot 365 days or i get an error otherwise)
Probably is because geothermal exploration drilling for a new power plant at that area. https://www.thinkgeoenergy.com/hs-orka-commences-geothermal-exploration-drilling-at-krysuvik-iceland/
Piton de la Fournais is probably doing a longer break. During the beginning of the year the volcano left an eruption cycle. The scientists assumed that Piton has to fill the magma reservoir first, before next eruption can begin. The last eruption was two years ago. The next eruptive cycle may begin with an above-average event like 1998. 1998 the eruption lasted for 196 days with a volume of 0.06 km³.
Last major break was 2010-2014. The last eruption cycle lasted for nine years (2014-2023). How long are the typical cycles? Often the eruptions are dense enough (in time) to be called episodes. 2018 were four episodes, more than probably 2025 on Svartsengi.
https://earthobservatory.nasa.gov/images/154666/swot-spots-tsunami-wave-after-kamchatka-quake shows satellite recording the Kamchatka tsunami from the 8.8 mag quake. I am surprised to see that it apparently originates well to the south of the epicenter.
I am not surprised by that!
Please share more.
For one, I had seen this before so that took the surprise away. But my reasons to expect this were that (1) in the 1950’s the tsunami was focussed further south, and (2) the rupture extended south from the epicentre and not much north, so the earthquake mainly occurred further south
Thank you, Albert, for the reply.
New post is up! “The Awakening”, by Tallis
https://www.volcanocafe.org/the-cerro-negro-problem/