#seismology

[todays-xkcd]

At least people who make religious predictions of the apocalypse have an answer to the question 'Why didn't you predict any of the other ones that happened recently?'

Earthquake Prediction Flowchart [Explained]

Transcript Under the Cut

[Caption above a flowchart:] Someone is claiming to predict the exact date of a future earthquake. Should you listen?

[At the top of the flowchart is a wide diamond with the following text:] Start

[An arrow points down to a rectangle with the following text:] NO (There are big earthquakes constantly, so if anyone ever does figure this out, it will be immediately obvious that their method works and the world's seismologists will not shut up about it. You won't need this flowchart.)

[miamaimania]

"3-D Seismology" (1981) ⧗ Fifty Fingers, Inc. ⌘ Before photorealism, the earth was a grid

[sepdet]

Youtube post of that Myanmar quake vid shown at different speeds and zoomed to highlight changes.

This really is the first time a side-strike rupture (sideways, as opposed to a head-on collision like Japan's) has been caught on video.

I will never again be confused what they mean by "right lateral" side-strike.

(I keep yammering on about it since I live 80-100 miles from the San Andreas fault, which has and will move the same way.)

[noosphe-re]

Displacement characteristics of body waves: (a) P wave, (b) S wave, and (c) Rayleigh (surface) wave.

Nam, Boo Hyun & Kim, Jinyoung & An, Jinwoo & Kim, Bumjoo. (2013). A Review on the Effects of Earthborne Vibrations and the Mitigation Measures. International Journal of Railway. 6. 10.7782/IJR.2013.6.3.095.

[longreads]

The Rip in the World

“At one point, we paused to take in the site of the 2021 eruption: a cooled lava sheet extending nearly to the horizon. Far in the distance, well beyond the marked trail, a few hikers took wide, delicate steps across the jagged basalt. Old lava is brittle; it tends to form hollow tubes, the insides of which can remain somewhat molten for months. Absentmindedly, our guide told us about an acquaintance of hers, a geologist, who once stepped on a section of lava he thought entirely cooled, only for his legs to break through the crust into the hot bubble below. She even described the smell. Then we were off walking again, keeping strictly to the trail.” 

As Jonah Walters recounts visiting Iceland to witness volcanic activity and his move to an earthquake-prone region of the United States, he wonders why humans are attracted to disaster. Check out The Rip in the World.

[mindblowingscience]

Scientists discover 'sunken worlds' hidden deep within Earth's mantle that shouldn't be there

A new way of measuring structures deep inside Earth has highlighted numerous previously unknown blobs within our planet's mantle. These anom

Potential patches of Earth's ancient crust, sometimes called "sunken worlds," may have just been discovered deep within the mantle, thanks to a new way of mapping the inside of our planet. However, these mysterious blobs appear in places they should not, leaving researchers scratching their heads. For decades, scientists have been building up a better picture of Earth's interior by using seismographs — 3D images created by measuring how seismic waves from earthquakes reverberate deep within our planet. This method has helped scientists identify ancient sections of the planet's crust, known as subducted slabs, that have been pulled into the mantle through subduction zones where tectonic plates meet. For example, in October 2024, researchers announced the discovery of a section of seafloor that had sunk deep into the mantle below Easter Island.

Continue Reading.

[scienceguy22]

The wobble that cannot be contained.

As I promised yesterday, today I will let you know the rest of the story of this fascinating dessert, Jell-O. Yesterday I told you about the new "Jello-O Meter" that measures sound & its intensity at concerts & stadiums. It all has to do with plain physics, actually. It has a sound-pressure sensor that uses a wobbly plate instead of a microphone diaphragm. When any crowd gathers, there is usually a lot of cheering, yelling, shouting & noise. The Jell-O contains a metal plate under which lies a metal plate that has piezoelectric motion sensor films & a mechanical actuator that jiggles the Jell-O. This is the physics of vibration analysis. The rowdier the crowd, the more it jiggles. It's already been used at a professional hockey game in NY that registered a 5.8 on the Jell-O Meter, which is normal cheering.

The energy is measured on an algorithmic scale, with 1 jiggle roughly equivalent to a microwave, while 10 is supposedly the same as a small earthquake, the equivalent of Taylor Swift's Seattle Eras Tour, where seismometers recorded ground motion equivalent to a 2.3 earthquake, dubbed a "SwiftQuake," caused by 70,000 fans jumping in rhythm. In Dublin (2024), seismic waves from "Shake it Off" were detected up to 60 miles away. Undoubtedly, those events would register a 10 on the Jell-O Meter. These registered 110-120 dB; however, they were nowhere near the loudest roar of the Arrowhead Stadium fans, which occurred in 2014 when the Kansas City Chiefs' roar registered 142.2, the loudest roar ever of any event that earned a title in the Guinness World Records. That's equivalent to the sound of a jet taking off; nevertheless, there was no seismic activity that shook the earth as in Swift's concerts because the Chiefs fans produced air pressure through sound—they weren't hitting the ground with their feet.

Jell-O was created by cough syrup & laxative maker Pearle Bixby Wait in 1897, but he knew he could make more money with similar ingredients, making a gelatin dessert, as they were expensive & were a luxury food for the rich in most of Western society. Jell-O only became "everyday" once industrial chemistry caught up. Pearl Wait's invention made gelatin cheap, pre-flavored, pre-sweetened & dissolved instantly, fast becoming a mass-market food, a kid food, a church-basement potluck food, a hospital food & a favorite 1950s housewife staple. It appears that noise levels are not the only thing Jell-O can measure. On March 17, 1993, technicians at St. Jerome Hospital in Batavia, NY, hooked an EEG machine to a bowl of lime Jell-O. And you know what? They found that the Jell-O produced brainwave-like electrical patterns identical to those produced by adult humans.

Does that mean that humans have the intelligence of a bowl of Jell-O? For most of us, the answer is no. EEG machines are extremely sensitive to electrical noise, vibration & electrode drift. A bowl of gelatin is a homogenous electrolyte gel, so electrodes can pick up ambient electrical interference that looks like human EEG rhythms. Jell-O has even been made in space. Shannon Lucid, a university student who eventually became an astronaut for NASA, flew to the Russian space station Mir aboard Space Shuttle Atlantis in 1996 and made weekly Jell-O in space. To make it in space is not easy since you can't safely boil water. Instead, they have a rehydration station where water is heated in a sealed pouch. That is sufficient to set gelatin, which sets between 59 and 77°F (15 and 23°C).

In the 1990s, Jell-O was used to predict the stock market after Kraft noticed that lime Jell-O sales rose during recessions. In the 1920s, Jell-O was used to smuggle alcohol into U.S. Navy parties, as alcohol was not permitted. It worked because gelatin traps ethanol in a semi-solid matrix, making it harder to detect. Teachers (including myself) use it to demonstrate wave propagation, resonance, vibration modes & seismic wave analogies. Clear Jell-O was used in photography in 1871 when photography companies began mass-producing gelatin plates with silver halide. After light enters a camera, it hits the gelatin layer & triggers chemical changes in the silver crystals, which turn into black metallic silver, & the ones that weren't hit stay unchanged. The gelatin acts as a fixer, keeping everything from washing away. Without gelatin, the picture would literally slide away. Jell-O is popular in college campuses, where they use it to wrestle in.

America went through a phase of tuna Jell-O, ham Jell-O, tomato aspics, and mayonnaise-gelatin snacks. But since the 1950s & continuing today, the #1 top flavor has consistently been strawberry.

[venomwrites]

Look i’m not really a numbers obsessed person on ao3 (i’m a comments obsessed one) but Seismology hitting 1k kudos right before these vows has me very emotional.

Thank you to everyone whose sent the fic some love.