Long period waves and their decay signature makes me suspect "water hammering" of a large volume of magma came to an abrupt stop inside a magma chamber or tube.
Tangent, but this place, which I knew basically nothing about before just now, appears to be stunningly beautiful, judging from the somewhat random sample of images on Wikipedia:
It's humbling... I feel like a bad citizen of the world for my ignorance of Mayotte. But also optimistic... the world is full of so many amazing places, there's always going to be some next amazing place to learn more about.
Pretty much every island near the equator looks like a tropical paradise. But appearances can be deceiving. A lot of these places are poverty stricken because of their distance from economic centers of the world. And many of these island paradises ( especially in the pacific ) have suffered ecological disasters due to introduction of invasive species by european explorers.
I think Attenborough did a documentary a while back on how the introduction of invasive cats, rats, snakes and even spiders would wipe out local fauna on these islands because the local fauna weren't used to predation. Pretty interesting stuff.
Also, the local population of these islands are suffering extreme health issues ( primarily obesity related ) due to all the junk food they are eating.
The nature is beautiful for sure, but it isn't all paradise. And we haven't even touched on the impact of global warming on these islands and the fact that some of these islands might have to be evacuated in the next few decades.
Listen to RNZI news (it streams), and you'll be surprised how many visually idillic Pacific Islands are wrought with military dictatorships, poverty, violence (gun, domestic, military), and worse.
There was one recent article about how a mission to distribute life-saving vaccines had to be abandoned because of a lack of infrastructure and trucks able to get to the villages that need it.
I spent a lot of time a few years back reading some Russian world traveller's photo blog (he looooved taking photos of signs and fire hydrants and such, which I wasn't super into but was sometimes interesting, but also posted plenty of other things—I misplaced the URL long ago or I'd link it) and the rule for off-the-beaten-path tropical paradises seemed to be that they were incredibly poor and absolutely covered in litter and improvised garbage dumps. If there were touristy sections it'd be every square meter of the place off the tourists' beach that looked like this.
Mayotte is a French oversea territory. And like almost all french oversea territory it is very poor, but less than the average neighbor countries leading to a lot of immigration which are difficult to control (even though Mayotte is an Island which make it a bit more controllable than Guyana for example). This usually end up in a increasing poverty and unemployment, leading to criminality, aging infrastructure, and public services not being able to handle the demand.
Like a lot of oversea territory, it has some beautiful landscape, but is crippled by the problems above. Living there is very difficult.
EDIT: Note also that I am not blaming immigrant. The problem being that adding more poor people in an already poor territory doesn't solve the problem of poverty. And France unwillingness to treat its oversea territory fairly and really invest in them is the main root of the problem.
The specific issue with Mayotte is that the other half of the archipelago has chosen to remain independent [1].
So on a very small territory you have a third world country, Comoros, and a piece of the European Union, where, even if it is not on par with continental Europe, has a much higher quality of life.
So there is a quite large influx of immigrants from Comoros, and this is hard to manage for such a small island.
[1] In 1974, France organized a referendum for self-determination in the archipelago in which the population except in Mayotte voted overwhelmingly in favour of independence. Following the unilateral declaration of independence in 1975, France maintained sovereignty over Mayotte. The three remaining islands formed the Etat Comorian, which later became the Federal Islamic Republic of the Comoro Islands.
This sounds a lot like Haiti. I was there on vacation for a couple of weeks. In general, Haiti dirty and poor, but there were some truly beautiful places. Unfortunately, only a few of them are actually available if you aren't there on either a cruise, or are friends/connected with the local 'bourgeoisie'.
One of the places that stuck with me the most is Kay Winnie in Seguin. It's a house, built by a man who moved there from the city in order to protect one of the last forests in Haiti. He grows and plants saplings to grow the forest. Unfortunately, you need to hike quite far or drive through incredibly rough terrain to get there.
Recently read 'The Comedians' by Graham Greene, which is set in Haiti during the rise of Duvalier. Those people have been through some terrible shit for a long time now.
> Those people have been through some terrible shit for a long time now.
Yup. And having been there and having spoken to locals and people from the UN, MSF, etc. I don't feel like it's going to change soon. A lot of the economy is driven by NGO's and that money all ends up in the pockets of the rich home, hotel and restaurant owners. Meanwhile the poor sell each other mangos and meat in the streets. It's like there are two completely separate economies. And whenever a politician wants to make a change, tribalism seems to end up ruining it because (often realistic) fear of preferential treatment of some groups.
>A lot of the economy is driven by NGO's and that money all ends up in the pockets of the rich home, hotel and restaurant owners. Meanwhile the poor sell each other mangos and meat in the streets.
Sounds eerily similar to the situation things rapidly deteriorate from at the start of the book, which was set 60 years ago now.
> Mayotte is the newest of the five overseas departments having changed from an overseas collectivity, with OCT status, on 31 March 2011. It became an outermost region and thus part of the EU on 1 January 2014.[8]
Yes. Some of the oversea territory had a weird status in the past (see openplatypus comment), but nowadays they are almost all DROM which mean, it is part of France, and being born there makes you French (and makes you a EU citizen).
I just saw a documentary about Réunion yesterday, an island in the vicinity with a unique culture & cuisine (a fascinating mixture due to colonization history) paired with great tropical nature due to (now inactive) volcanoes that created some beautiful hiking trails in craters and calderas. All those little islands around Madagascar seem to be really lovely and beautiful, they are certainly on my ToDo travel list now.
Been there some years ago for two weeks of paragliding. One of my best memories for sure, beautiful island, very clean waterfalls.. There's an active volcano though [1]..
What do you mean, 'though'.. that's another plus! It's monitored so it won't go off and kill people without warning and time for evacuation.
And it's Hawaiian style, which means very fluid and low ash, which is the most fun style of volcanoes because it won't really explode (the gas can escape steadily instead of building up pressure) and you can get pretty close during an eruption.
Worst case, your flight is delayed or cancelled and you cannot stay in a specific village. Best case, you get to see an awesome and safe display of natural forces!
I think "though" was in reaction to the GP saying that the volcanoes on the island are inactive. I was going to say the same thing, the piton de la fournaise is very much active.
Thanks, guess I misinterpreted the documentary, they were only talking about huge calderas from former eruptions. Or I missed the part where they talked about the active volcano (multitasking, meh ...).
I live there, it's a bit exagerated. But I wouldn't recommend coming in the forecoming month. If you really want to come feel free to ping me if you need some advice.
my favorite:Good questions! A simple body wave M may underestimate and simple surface wave M may overestimate, but a waveform-based moment-tensor inversion type M for the surface waves may confirm shallow depth and produce a usefully accurate M...
Thanks for those links. Some of the commentary speculates that a magma chamber emptied a bit and its roof collapsed as a result of a quake, and that collapse is the source of the low-frequency waves. Fascinating.
Seismologists invented FFT signal processing. Rumors circulate at oil companies that many companies discovered it independently and were using it internally years before the method was openly published. It would be hard to underestimate the value of FFT processing to that industry.
Clearly, the wave is from movement and noise generated by a large (multi-mile long) subterranean hard drive or processor or machine spinning to life after having been given the "wake on LAN" (or some other SSH/RDP-like) signal from Oumuamua [1] - who just got into wifi range earlier this year. The signal is just too clean for it to be natural; it must be artificially generated. So, its either aliens returning, or some Earthly code recently got deployed for Earth 2.0. (Oh, did you think we were living in Earth 1.0...Hmmm, interesting. Do you also think that's air that you're breathing?) ;-)
I have some requests I'd like to see in the next update:
1. nerf mosquitoes
2. are hemorrhoids even necessary? I think we can just trash that feature.
3. human ingestion is quite buggy. often times nutritional data gets routed incorrectly. plz fix
During recent sprint retrospectives, product owner continues to battle for the need to include hemorrhoid features, hence the constant addition of user stories. Needless to state, none of us is a fan of this set of hemorrhoid features...but product owner is quite, er, um, powerful. But the nerf mosquitoes; yeah we can put that one in! For human ingestion, we'd need a little more details for a user story there. :-)
"For human ingestion, we'd need a little more details for a user story there. :-)"
well, I was attempting to route some potato data to my food decompounder for processing and it was mistakenly sent to the air intake vent. suffice to say this disruption of the norm caused a break in workflow.
Thanks, this is clear now; and will be added as a user story for the next sprint.
By the way, i figure i should caution you that I've heard other users leveraging a temporary hack - while awaitjng this feature to be built/deployed - of routing potato (and other such) data via other intakes. In fact i think there was a SouthPark episode related to this hack; in that case using turkeys as the routed data.
This happened before, i had forgotten about it. But it was posted on some forum, and they could track the seismic waves as they traveled from the eastern US to the western US - and they were exceptionally fast... but the interesting thing of when that particular event happened was that the speculation was it was the detection of secret underground high-speed transports, between DUMBS...
Other than it being an interesting fanciful thought to imagine if such a thing could be, i didnt think much of it.
But this is interesting in that the waves were also tracable from seismometer to seismometer...
You should know that there was a patent filed in the late 60s for a tunnel-boring-machine which used a nuclear reactor as its power source, but also used the heat-output of the reactor to melt the earth surrounding the tunnel it was boring so as to make a structurally sound tunnel
I'm always concerned when people use an acronym as if everyone knows what it means, when it is in fact a fairly niche acronym. It shows people maybe haven't talked about their ideas to folks outside of a certain group with preexisting notions.
"Mayotte is on the move. Since mid-July, GPS stations on the island have tracked it sliding more than 2.4 inches to the east and 1.2 inches to the south."
If this isn't a mistake, it's also very interesting. 2.7 inches in four months is very fast. That's 20 cm/year. The fastest techtonic plates move about 10 cm/year. Also this island does not appear to be near a plate boundary, so what could make it move? The article didn't say what it was moving relative to.
That is a large amount. I don’t think the rate of tectonic plate movement relates to the amount of land movement very well though. New Zealand is shuffling around all over the place in silent quakes by about that much, and in the not-at-all-silent quakes it’s been metres of movement. The last decade has been rather wobbly.
Local geology can play a pretty big role in observed velocities, but I agree these are pretty quick. The velocity changes in the figures are really interesting, and I agree much faster than plate motions. I'd wager that there is some kind of slow or aseismic slip happening. Slow slip events
There are notes on the displacement time series though they are in french.
> [After the 2010 Chile earthquake] A research collaborative of Ohio State and other institutions have found, using GPS, that the earthquake [...] moved Concepción at least 3 metres (10 ft) to the west. [...] Several cities south of Cobquecura were also raised, by up to 3 meters.
Just because one uses GPS to measure position does not mean one is calculating position in WGS84, the GPS native geodetic datum.
For instance many survey instruments use Differential GPS to obtain a more precise location by using corrections from a receiver at a well-established survey mark. When using DGPS the coordinate system becomes that of the reference mark, not the GPS system.
So I think the question is relevant, and takes note of the context in which ground motion is studied.
This was my understanding from the article; there's probably a magma chamber shifting in some way, and resonance of pressure waves inside that chamber is causing outward waves to be projected around the earth. The metaphor I imagine is a boat in the middle of a lake having a sudden (non-explosive) hull breach that causes it to fill with water and rock rhythmically side to side. As it rocks, ripples from the boat extend outward in the lake at the same slow frequency that the boat is rocking, eventually spreading out through the entire lake.
I don't know a thing about fluid dynamics. This is just a layman's understanding. But the idea is that as water rushes in from the hull breach, it then sloshes from side to side. It's rhythmic based on the size of the boat and how long the water takes to slosh back and forth.
I don't like feeling like a conspiracy theorist, but those signals look really clean [0]. Not necessarily the military, but... it's so intentional-looking.
> “They're too nice; they're too perfect to be nature,” she jokes, although she quickly adds that an industrial source is impossible, since no wind farms or drilling are taking place in the deep waters off Mayotte's shores.
And
> For now, though, the lack of data makes it tough to say more about the wiggly forms. Hicks' preliminary models hinted that the waves emanated from subsurface inflation, rather than a magma chamber draining or collapsing. But with a little additional data, the model flipped and pointed to chamber deflation instead.
Does lend a grain of salt toward the military theory.
"“They're too nice; they're too perfect to be nature,”"
Nature does on occasion surprise us with nice clean signals; for instance, the history of pulsars, where the initial signals were so clean that people couldn't help but suspect they were artificial (and I do not mock them for that, it was a reasonable thing to put on the initial pile of theories): https://en.wikipedia.org/wiki/Pulsar#History_of_observation
The universe is still low-entropy, and will remain so for the forseeable future. Things like this can still naturally happen.
I wonder as polar ice melts and the weight distribution on earth changes because of it if the planet wouldn't twist a little bit while spinning and cause earthquakes, even if just small ones.
The abstract on this [1] makes me think something similar could be happening here: low attenuation implies the resonance would take quite a number of cycles to die out like the one discussed in the article.
Here’s another abstract [2] describing resonance with periods near 10 seconds lasting a long time.
I have essentially zero knowledge of how all this stuff works but I wonder if this is from something going on much deeper in the Earth, like perhaps the very core itself just gurgled on a chunk of Earth that fell in or something.
> “They're too nice; they're too perfect to be nature,” she jokes, although she quickly adds that an industrial source is impossible, since no wind farms or drilling are taking place in the deep waters off Mayotte's shores.
Today I learned that seismologists have to take in to account wind farms when filtering noise.
Tracked down this reference to: N. K. Jemisin - the first in the series being The Fifth Season, winner of the Hugo Award for Best Novel 2016. Thanks for the reading tip!
I wonder if it has to do with activity in the Great Rift Valley to the northwest? A continent being split in two must cause some odd behavior for an entire region.
Not a nuclear test because there's no initial transient.
This is more like a forced resonance - the geological equivalent of an organ pipe.
So I'd guess there's a pipe-like feature or a chamber in the area (an old magma tunnel? - it doesn't have to be empty, it just needs to have a constant density significantly different to its surroundings) and "noise" from moving magma made it to ring.
With a 17s period and 6km/s velocity, for lambda/4 resonance the pipe/chamber would be around 30km long - which looks not-completely-insanely-wrong, possibly.
As you can see, there are seismic station for detecting underground tests (the signal differs from earthquake signals if you look at stations around the world), acoustic and hydroacoustic stations for detecting tests in the atmosphere and oceans, and isotope detection to differentiate between any kind of explosion and a nuclear one (which leave the same signal in the other detectors).
The stations have a fantastic global coverage and have been measuring for quite a while. The data set is now also given to the scientific community for all sorts of purposes.
The comments here so far are one reason I prefer HN. If this was reddit the first post undoubtedly would have been a meme pic with the phrase "Aliens!!" :)
>>The comments here so far are one reason I prefer HN. If this was reddit the first post undoubtedly would have been a meme pic with the phrase "Aliens!!" :)
Sometimes you need to tell the truth, right away. :)
From the article looks like a large body of magma is trying to see the daylight
They talk in real life how hackers talk only in movies. Very jealous.
https://twitter.com/matarikipax/status/1061590953876582402
https://twitter.com/ALomaxNet/status/1061637338709790721