Earth Tipped on Its Side 84 Million Years Ago, New Evidence Suggests

Posted: November 14, 2021 by oldbrew in Analysis, Geology, Geomagnetism, History, paleo, research, solar system dynamics
Tags:

Diagram showing solid-body rotation of the Earth with respect to a stationary spin axis due to true polar wander. [Credit: Wikipedia]

The researchers say their finding ‘challenges the notion that the spin axis has been largely stable over the past 100 million years.’
– – –
We know that true polar wander (TPW) can occasionally tilt whole planets and moons relative to their axes, but it’s not entirely clear just how often this has happened to Earth, says ScienceAlert.

Now a new study presents evidence of one such tilting event that occurred around 84 million years ago – when dinosaurs still walked the Earth.

Researchers analyzed limestone samples from Italy, dating back to the Late Cretaceous period (100.5 to 65.5 million years ago), looking for evidence of shifts in the magnetic record that would point towards an occurrence of TPW.

Bacteria fossils trapped in the rock, forming chains of the mineral magnetite, offer some of the most convincing evidence yet of true polar wander in the Late Cretaceous – and it may help settle a scientific debate that’s been going on for decades.

“This observation represents the most recent large-scale TPW documented and challenges the notion that the spin axis has been largely stable over the past 100 million years,” the researchers explain in their paper.

Earth is made up of a solid metal inner core and a liquid metal outer core, with a solid mantle and crust (the surface) moving slowly around on top of the liquid metal. Earth’s magnetic field, generated by the outer core, is recorded in rocks like the ones studied here.

True polar wander is when the geographic poles shift substantially, so the outer wrapping of Earth tilts over. Nothing actually changes in terms of Earth’s magnetic field, but the shifting rocks will record different paleomagnetic data as they move.

That data reveals the distance to the North and South geographic poles, enabling researchers to plot where these poles actually are. A fully vertical field means a rock was at the pole, while a fully horizontal field indicates it was at the equator.

“Imagine looking at Earth from space,” says geologist Joe Kirschvink, from the Tokyo Institute of Technology in Japan. “True polar wander would look like the Earth tipping on its side, and what’s actually happening is that the whole rocky shell of the planet – the solid mantle and crust – is rotating around the liquid outer core.”

According to the study, there was around a 12 degree tilt on Earth around 84 million years ago, which was corrected relatively quickly – within about 5 million years, the equivalent of a “cosmic yo-yo” in the words of the researchers.

What that means is that these rocks – and Italy itself – took a journey towards the equator before tipping back.

Full article here.

Comments
  1. Jim says:

    Interesting, but incomplete, and off kilter suppositions manifested. This assumes no expansion, subduction, or scum wandering. Earth, is and has always been this way. Err, no. The poles wander, as do the continents, a little east west or north will throw off his statement. But an interesting read,

  2. oldmanK says:

    Now I had to look a second time at this article – but ‘no comment’ in general.

    However it is evident that tectonic rotations, especially in the Med, are now being an accepted concept. In paper – here: https://www.nature.com/articles/s41467-021-23803-8.pdf last para “Local tectonic restoration of northern Umbria.” indicates that evidence of tectonic rotations exists. There are a good number of other papers relating to Med tectonic rotations.

    It is, IMO, not an easy matter to work out paleomagnetic records from what is a continuous/repetitive tectonic process which is widespread in the Med; and then so far back in time.

    But tectonic rotations is a very evident process in the axial orientation of megalithic calendars that need to be axially aligned to equinox sunrise. Those give clear evidence of rotation, with a relatively recent date. Additionally they also give a clear indication that it is not polar wander but axis tilt change.

  3. Curious George says:

    And a geomagnetic reversal means that the whole Earth shifts upside down 🙂

  4. oldbrew says:

    According to the study, there was around a 12 degree tilt on Earth around 84 million years ago, which was corrected relatively quickly – within about 5 million years, the equivalent of a “cosmic yo-yo” in the words of the researchers.

    Obviously other ‘corrections’ must have occurred since, as the tilt range is about 22-24.5 degrees now.

  5. JB says:

    “Earth is made up of a solid metal inner core and a liquid metal outer core, with a solid mantle and crust (the surface) moving slowly around on top of the liquid metal.”

    Well we know this just isn’t true. That documentary movie that came out in the 1950’s, Journey to the Center of the Earth, proved there were dinosaurs living down there! With sunlight no less!

    With all the various pole shifts throughout history (e.g. Noel, M, and D H Tarling. 1975. “The Laschamp Geomagnetic Event”, Nature, voI 253, pp705-706; see fig 2 on p705.), I’m trying to figure out the significance of this is latest “finding.”

    I am so astonished at how people believe they know for a surety about the ancient past when they can’t make up their minds about the climate in this century yet to unfold.

  6. Phoenix44 says:

    Oldbrew, I believe your numbers refer to the celestial tilt rather than an axial tilt.

  7. John MacDonald says:

    The tilting diagram would look better if the long ago glide picture reflected the tectonic plate arrangement in place at that time. At least the Atlantic was much narrower.

  8. oldmanK says:

    There appears to be a confusion of terms and their effect.

    From first line in paper (link to pdf above in my prev post), thus “True polar wander (TPW) is the reorientation of a planet or moon in order to align the body’s greatest nonhydrostatic principal axis of inertia (Imax) with the spin axis”

    There is the spin axis (oldbrew’s 22 to 24.5deg) tilt or ‘obliquity’ with respect to ecliptic plane, and separately, according to paper, the crust+core? Imax vector.

    However there is also the magnetic axis which is different than the geographical axis. Maps give this difference for correcting between compass reading and the geography.

    Then there is also crust drift, which is likely not linked to any of the above, and dependent on tectonic plate movements.

    Then add the fact the earth is not a homogeneous body, see video after 10:00 https://www.youtube.com/watch?v=5CdlOKpJUyQ

  9. oldbrew says:

    Paper: Although TPW for the past 100 Myr may be of smaller amplitude than earlier TPW shifts, our high-resolution palaeomagnetic study would suggest that one cannot rule out the possibility of rapid TPW shifts of small amplitude (<20°) in the most recent past.
    – – –
    Phoenix – see here…
    https://en.wikipedia.org/wiki/Axial_tilt

  10. hdhuffman says:

    Again, yet another example of science fundamentally corrupted, down to its false uniformitarian, meaningless Darwinian roots.

    I have long ago informed you all of the “Great Design of the ‘gods'”, and when it occurred (the Design’s central, governing image tells us exactly, in terms of a constant precession: 15,128 BC, +/- 20 years. It also tells us precisely the celestial position of the former ecliptic axis, with supporting details in ancient myths.

    It was not “accidental”, it was not an uncontrolled world change, and it was not millions of years ago. The whole Earth and Solar System were re-formed and re-oriented.

    And oldbrew, the obliquity is 23.5°, long-term and stable. See my 2016 blog post on Milankovitch theory

    Why I Don’t Believe in Milankovitch

  11. attisToCy says:

    Reblogged this on attis.

  12. oldmanK says:

    Harry: you have put your trust in two unreliable people.

    One was Simon Newcomb. He asserted that “the obliquity is 23.5°, “long-term and stable”. No proof of that; in fact the evidence points otherwise. J F Dodwell had discerned the obliquity change of 2345bce, and evidence of that is now mounting. Milankovitch had assumed that Newcomb was correct.

    The other is Ptolemy. See link http://dioi.org/jm02.pdf
    and
    https://www.jhuapl.edu/Content/techdigest/pdf/V06-N02/06-02-Newton.pdf last page

    “In the course of these studies, Newton became a superb scientific
    detective, analyzing both internal and external evidence to determine
    the probable reliability and accuracy of ancient observations.
    He discovered numerous errors and discrepancies in both observations
    and analysis and, most notably, was forced to the conclusion
    that Claudius Ptolemy had fabricated all the data he claimed to have
    measured himself and much of the data he attributed to others. That
    shattering conclusion-for Ptolemy was the most distinguished name
    in astronomy prior to Copernicus and his work had been thought
    to be both the summary and epitome of Greek science-was
    thoroughly documented in The Crime o/Claudius Ptolemy (1977),”

  13. oldbrew says:

    From Wikipedia: ‘The Gnomon of Saint-Sulpice is an astronomical measurement device located in the Church of Saint-Sulpice (Église Saint-Sulpice) in Paris, France. It is a gnomon, a device designed to cast a shadow on the ground in order to determine the position of the sun in the sky.’
    . . .
    Obliquity of the ecliptic

    ‘Le Monnier further used the gnomon from 1744 to establish the variations of the ecliptic, or the variations in the obliquity of the Earth’s axis.[5] The endeavor is recorded on the plaque at the southern end of the meridian, in the South transept: “Pro nutatione axios terren. obliquitate eclipticae” (“for the nutation of the earth’s axis and the obliquity of the ecliptic”).[5]

    As mentioned on a brass plaque that covered the stone plaque, the obliquity of the ecliptic was 23°28’40”.69 in 1744.[5] From 1745 to 1791, Le Monnier visited Saint-Suplice at each summer solstice and, focusing the light with a lens fixed to the opening in the stained-glass window so as to produce a sharp image of the sun on the floor, noted the exact position of the image at noon. From these observations, he calculated a variation of the obliquity of 45″ per century (the exact figure is 46″.85 per century).’

    https://en.wikipedia.org/wiki/Gnomon_of_Saint-Sulpice#Obliquity_of_the_ecliptic

    the exact figure is 46″.85 per century – presumably the mean value as it’s not a constant rate.
    – – –
    The plaque at the southern end of the meridian, mentioning the work on the obliquity of the ecliptic

  14. stpaulchuck says:

    John MacDonald says:
    November 15, 2021 at 6:37 am brings up an interesting point. Did the moon or a close passing mini planet cause tectonic shifting that “lumped” too much crust at one point causing a nasty wobble that caused a shift and then scattering of the crust to a more even distribution…??

    You’ve seen ceiling fans that are off balance dancing around. If the blades could move around they would tend to either completely fly off or redistribute to a more balanced mode from models of this sort of behavior I have seen.

    An interesting conjecture.

    Also, did we have an impact (or two) that we have not discovered yet?

  15. Paul Vaughan says:

    This otherwise interesting presentation appears to ignore (or perhaps deliberately misrepresent?) clearly observed Milankovitch spatiotemporal pattern (at precession timescale) :
    https://wattsupwiththat.com/2021/11/14/global-water-cycle/
    (I’ve stopped my years-long boycott on monitoring the site.)

  16. Paul Vaughan says:

    The gameplan there appears to be: get people to look somewhere other than where observations clearly point — the usual trick — same one as with 66, 96, & de Vries. The optics: I suspect some influential folks who know better (tongue-in-cheek privately) direct people to look 99% credible and leave out the “control” ingredient (left for a small group of billionaires …or whatever).

    Pay careful attention to where the author looks for the precession signal …and wonder why the author doesn’t even mention where it is CLEARLY OBSERVED.

  17. Paul Vaughan says:

    Supplementary

    + censored animations retrieved from wayback:

    column-integrated water vapor flux with their convergence

  18. Paul Vaughan says:

    Another classic for review:

    supplementary:

    Egregious Milankovitch misrepresentation appears widely encouraged. It has the smell of a very strongly coordinated effort — one of the most suspicious things I’ve observed on climate blogs. It must be considered important by someone with big influence because simple, BIG blunders keep getting pushed. Another possibility I’ve considered: it’s just being done on purpose to stir the pot – or maybe just to get people to learn more – so they can know better privately but expect rude censorship if they speak up.

  19. Paul Vaughan says:

    Equally suspicious: the “global water cycle” article mentions neither EOFs nor interhemispheric throttle.

    Leaving it there for now.

  20. oldmanK says:

    PV appears concerned about “Egregious Milankovitch misrepresentation”. On a personal level, I have an issue with that guy, in somewhat the same manner as Claudius Ptolemy and Simon Newcomb. In theory Milankovitch is correct, but the application of that theory is very wrong when it ignores other factors.

    Dynamic systems are subject the secular cyclic forcings, but more important are the ‘step’ (read abrupt) short duration forcing signals that alter the mean or parking point of the secular continuous signals.
    Milutin Milanković (28 May 1879 – 12 December 1958) would have heard [or maybe not] of George F. Dodwell (1879–1963). The question of the discrepancy between Newcomb’s calculations and the old measurements of obliquity was known to some extent, because Axel Wittmann also produced a paper in 1979 that studied those discrepancies.

    No one to date explained why today’s mean of the obliquity variations’ is parked at some(?) 23.2deg. Or for that matter the tilt of the other planets doing the rounds in the ecliptic plane.

    One would expect that ‘most’ forcing signals to be evident in some proxies, however that explains little. It is discontinuities that are of greater concern. Dodwell pointed to a possible discontinuity at 2345bce (for which there is now sound evidence). The result of that is the 4k2BP event that ravaged humanity. An earlier one that was very elusive, but now better known, was the 5500BP that desiccated the Sahara. The latter has never to date regained its original value as a habitat for man and beast.

    The dogma circulating around those three people imo has been more of a curse than a blessing.

  21. Paul Vaughan says:

    oldmanK has repeatedly and correctly stressed the point that there is a next level of modeling — i.e. subtract out observed Milankovitch (to be neither confused nor conflated with theory), then study the residuals …which contain a large proportion of the variation where discrete material factors challenge next-level perception.

    This is just like with solar cycle deceleration (interhemispheric throttle) and ENSO being a left-over accounting for a high proportion of variance (around the central limit).

    Maybe a small rich group of influential investors wants people on equatorial continents mislead (perhaps into deep northward misunderstanding based on improved infrastructure).

    My counter-suggestion: concise honesty about Milankovitch, including honesty about residuals that invite deeper exploration.

    Regards

  22. oldbrew says:

    Published Online: 16 November 2021
    Automatic detection of abrupt transitions in paleoclimate records

    Bifurcations and tipping points (TPs) are an important part of the Earth system’s behavior. These critical points represent thresholds at which small changes in the system’s parameters or in the forcing abruptly switch it from one state or type of behavior to another.
    . . .
    For the sake of brevity, we assume for the moment that each jump in the time series identified by the methodology described herein is equivalent to an abrupt climate transition and use jump and abrupt transition interchangeably.
    . . .
    Here, we present a methodology for automatically detecting abrupt transitions in paleoclimatic proxy records of many types and on several time scales. This statistical method is based on the Kolmogorov–Smirnov test and it can be applied to different types of records extending over distinct time spans, thus allowing one to objectively compare them. The jumps so identified in climatic time series may then be further explored with a full hierarchy of models to improve our understanding of the Earth’s bifurcation mechanisms and identify possible TPs for future climates.

    https://aip.scitation.org/doi/full/10.1063/5.0062543
    – – –
    Phys.org article here: https://phys.org/news/2021-11-climate-abruptly.html

  23. Paul Vaughan says:

    commentary on OB’s last comment

    don’t exist (publicly) :
    1. theory of *spatio*temporal chaos
    2. concise statement of classification theorem

    another challenge is material – e.g. hammer something on a schedule, it doesn’t necessarily break, rotate, twist (or whatever) on every strike

    discrete changes in topology of circulatory knots – there should be plenty of scholarly material on this subject …but in climate discussion we never hear of it
    96 is a SOLID example sensible parties simply cannot dismiss …or even challenge

    interhemispheric throttle – keep in mind engine-size change (with same level of throttle or rate of throttle change)
    (in past I used gear-shift analogy, but really it’s engine-size)

    sensible discussion of pattern evolution is barely nascent

  24. Paul Vaughan says:

    “Maybe a small rich group of influential investors wants people on equatorial continents misled (perhaps into deep northward misunderstanding based on improved infrastructure).”

    Elaboration on the strategy (as it was relayed to me) :
    1. major power invests in equatorial continent infrastructure (which eventually matches north).
    2. misinformation (including climate misinformation) stokes extreme northward anger.
    3. major power harvests benefits in ~50 years.
    (then I was told westerners aren’t supposed to know about the strategy)

    Persistent, aggressive misrepresentation of Milankovitch observation (to be neither confused nor conflated with theory) is consistent with the game plan outlined by the strategist.

    Repeating my suggestion: concise honesty about Milankovitch, including honesty about residuals that invite deeper exploration.

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