[HN Gopher] Forces deep underground seem to be deforming Earth's...
___________________________________________________________________
Forces deep underground seem to be deforming Earth's inner core
Author : walterbell
Score : 49 points
Date : 2025-03-06 07:46 UTC (2 days ago)
(HTM) web link (www.newscientist.com)
(TXT) w3m dump (www.newscientist.com)
| cmrx64 wrote:
| https://archive.ph/J776a
| admissionsguy wrote:
| That's a great headline. Maybe not for a non-fiction article, but
| a great headline nonetheless.
| xg15 wrote:
| Yeah, gotta admit, had to think of Lovecraft for a second.
|
| Would also fit the weird events in Italy's Campi Flegrei and
| Greece's Santorini island recently.
|
| No, I'm not serious :)
| knighthack wrote:
| The underground lizard people doing their thing, of course.
| jb1991 wrote:
| The headline only needs one minor twist also to give some
| political entities a reason to blame climate change on
| something other than the burning of fossil fuels.
| amelius wrote:
| If you like that headline, you will love this movie:
|
| https://www.imdb.com/title/tt0298814/
| Zigurd wrote:
| A title like: we can detect forces inside the Earth that deform
| it, even though the Earth overall is smoother than a ball
| bearing, just wouldn't get enough clicks.
| neonsunset wrote:
| Geothermal drilling has awakened the deep ones
| buryat wrote:
| dug too deep and awakened balrog
| 47282847 wrote:
| Interesting choice of words. De-formation implies that it was
| well-formed before. Not every change of form however is a de-
| formation. It includes judgment from "better" to "worse".
| marky1991 wrote:
| I don't think so, 'deformation' can also just mean any
| arbitrary change of shape, and in a physics/engineering
| context, that's usually all it means.
|
| From websters: 1. alteration of form or shape
| also : the product of such alteration 2: the action of
| deforming : the state of being deformed 3: change for the
| worse
|
| so it's just sense 1.
| PaulDavisThe1st wrote:
| In english, the word is almost always used to refer to
| "alteration of form or shape" _away from the default form or
| shape_.
| kergonath wrote:
| Not really in mechanics (or geophysics). Most of the time
| there is no sensible default, and we talk about reference
| instead. But then that's just muddying the waters. Here,
| "default" is utterly meaningless, for example.
|
| The long and short is that deformation means just that the
| shape of something changes.
| jofer wrote:
| The article kind of glosses over a key point about how all of
| this works and why "rotation" vs "shape changing" are difficult
| to distinguish. That's all because of anisotropy of seismic
| velocity in the inner core.
|
| In other words, sound (seismic waves) travels much faster in one
| direction than the other through the inner core. That's true of
| most rocks to some degree, and it implies that the crystalline
| iron in the inner core is mostly aligned in a similar direction.
| But that is at the core (pun intended) of all of this.
|
| So the "fast direction" has subtly changed over time based on the
| data we have. That's the "the Earth's inner core rotates
| differently than the rest" part. But we're mostly basing that on
| travel times in each direction (it's more complex than that -
| more in a bit). The differences "more fast stuff" and "less
| slower stuff" are hard to distinguish precisely, though they can
| be distinguished because of effects that occur at the boundary
| between different velocity + density bodies. It's also harder
| because the outer core is liquid and removes a key source of
| information coming from wave interactions at those boundaries
| (shear waves).
|
| This is basically doing a lot of clever reprocessing of old data
| to carefully look data after corrections for the moderately-well-
| constrained rotation of the inner core. Rotation of the inner
| core can't explain all of the differences, so another thing that
| might cause it is changes in the shape of the boundary between
| the inner and outer core. It's also possible it's noise, though
| presumably the authors investigated that part carefully (haven't
| read the scientific article, but the primary author is a very
| well known person in the field, so the analysis is likely very
| sound).
|
| There are always alternate explanations, though. Changes in shape
| on the order called for here do need an explanation via
| geological processes. Kilometer scale changes in a decade are
| difficult to immediately explain, though not impossible. I have
| no doubt the analysis is sound, but from a geologic perspective,
| this (and previous) work raises a lot of interesting questions.
| jofer wrote:
| On a side note,
| https://www.science.org/content/article/scientists-probing-s...
| is a good pop sci article on the context.
| Andys wrote:
| Additionally, the magnetic shape and location of the poles are
| also shifting, which I think suggests the core is also shape
| changing.
| awinter-py wrote:
| not now, forces deep underground
| zoomzoom wrote:
| This correlates (in a scary way) with some interesting
| hypothesizing I've seen about possible cataclysims from earth's
| core changing within human history:
| https://theethicalskeptic.com/2024/05/23/master-exothermic-c...
| lofaszvanitt wrote:
| newscientist is full of shit, just like wired
___________________________________________________________________
(page generated 2025-03-08 23:01 UTC)