900-mile mantle pipeline connects Galápagos to Panama | Hacker News Reader

900-mile mantle pipeline connects Galápagos to Panama

news.cornell.edu

54 pointsPaulHoule11 comments

A little cringe... as someone who listens to geology podcasts, the idea of "hot spots" apparently doesn't hold much scientific scrutiny any more. This will probably take another decade to be phased out since everyone is taught in school Hawaii etc. are created by hot spots/mantle plumes.

The newer explanation is actually simpler and explained by plate tectonics... deep extensional faults in the middle of plates (generally at stress change boundaries, since the plates are stressed differently at opposite margins) is sufficient to get these island-forming magma extrusions.

EDIT - by request, my favorite geo podcast is Oliver Strimpel's Geology Bites.

Off-topic, but can you recommend some geology podcasts, either science-centric or for the layperson?

An acquaintance of mine is a big fan of Nick Zenter's videos on Youtube.

https://www.youtube.com/user/GeologyNick

I liked Dick Gibson's History of Earth podcast https://historyoftheearthcalendar.blogspot.com/

And Dr. Christian Shorey Earth and Environmental Systems podcast https://geology.mines.edu/sygn101-podcasts/

Interesting, could you point at some further reading?

My wife studied volcanology, I helped her with some of the maths involved, seems like a fascinating subject!

I'm also curious about this change in terminology. I used Google Scholar for papers in 2021 and easily found geology papers using the term "hot spot".

> Hot spots are the surface expression of plumes of hotter and lighter material upwelling from the Earth’s mantle. The current number of hot spots is estimated to range between 45 and 70: these are mostly in intraplate settings, especially on oceanic lithosphere, and along divergent plate boundaries. - https://link.springer.com/chapter/10.1007/978-3-030-65968-4_...

> Regardless of the nature and origin of hot spots and whether they are fixed or mobile, the fact remains that there is a major thermal anomaly under Iceland, commonly referred to as the “Icelandic hot spot”. - https://onlinelibrary.wiley.com/doi/abs/10.1002/978111985092...

> The Cape Verde Islands are considered as the surface expression of a mantle plume at 500–800 km west of the African continental margin. The spatial and chronological evolution of volcanic activity, from East to West, is consistent with the slow progression of the African plate over the hotspot since at least the Oligocene - https://www.nature.com/articles/s41598-021-96897-1

> Mantle plumes were discovered almost 50 years ago by Morgan and Wilson. They are long-lived (up to ~100 Ma) jets of hot matter rising from the bottom of the mantle and burning through moving lithospheric plates and continents in hot spots, forming large magmatic provinces. - https://link.springer.com/article/10.1134/S1028334X21090191

To be clear, this only shows that some geologists use the term. It may be a small and decreasing minority found only because that's the specific search term I was looking for.

The hot spot versus plate movement/stress debate has been going on for many decades. Some hot spots are likely mostly caused by tectonic stress differences, but others seem likely to be from plumes. Scientists get published for novelty more than correctness, so if a theory is around for awhile and another can explain something in a different way, it is more likely to be published. Isotopic chemical data does suggest some volcanic sources come from the mantle (deep in the earth) where others are more likely crustal melting, which can be caused by tectonic decompression. I would be interested if you have a source of a review paper on the current ideas on hot spots, if you have it.

I understand the article to be saying that there is a water spring in Panama that is fed by a source in the Galapagos Islands. Is that correct?

The way I read it is, the water spring is fed from whatever lies under Panama. However, there are a lot of helium isotopes in the water from that spring. It is theorized that the helium isotopes come from the magna flow from the Galapagos, which gets into the water. IOW, the water is from Panama, but the magma (as thus, the helium isotopes) come from the Galapagos. Regardless, the interesting part is that no matter where that water comes from, magma can apparently spread out laterally rather than just making islands and volcanoes.

But that's just my reading, I'm probably just as confused.

No.

[Remainder to understand my explanation: When "lava" is under earth, it's called "magma". I had to look at Wikipedia because I never remember. https://xkcd.com/903/ ]

There is a big mantle plume under the Galapagos islands https://en.wikipedia.org/wiki/Mantle_plume . Imagine a lot of magma, and some part of it escapes and goes to the volcanoes and you see it as lava.

They discovered that there is a "river" of magma that goes from the plume of magma under the Galapagos to Panama.

In Panama the magma meets some underneath water, an some of the gas disolved in the magma goes to the water. Then the water colds down, and after some time it appears in a few springs in Panama.

They realize this, because they analyzed the gases disolved in the water of the springs.

There is no water traveling from the Galapagos to Panama.

"There is no water traveling from the Galapagos to Panama."

Thank you.

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