The Day the Earth Fell Over

Guest “Klaatu barada nikto” by David Middleton

My apologies to Robert Wise, Edmund H. North, Harry Bates, Michael Rennie and the guy who played Gort in the 1951 classic, The Day the Earth Stood Still… For some reason, this article made me think of the movie (the 1951 version, not the dreadful Keanu Reeves remake).

NATURE
Earth Tipped on Its Side 84 Million Years Ago, New Evidence Suggests
DAVID NIELD 20 OCTOBER 2021

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.

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

[…]

Science Alert… (Be alert! We need more lerts!)

Good fracking grief! There is no evidence that “Earth tipped on its side 84 million years ago.” The Science Lert is a “tech journalist” with a BA in English. So, that might be how he misunderstood what the “new evidence” suggested.

A Late Cretaceous true polar wander oscillation
Ross N. Mitchell, Christopher J. Thissen, David A. D. Evans, Sarah P. Slotznick, Rodolfo Coccioni, Toshitsugu Yamazaki & Joseph L. Kirschvink
Nature Communications volume 12, Article number: 3629 (2021)

Abstract
True polar wander (TPW), or planetary reorientation, is well documented for other planets and moons and for Earth at present day with satellites, but testing its prevalence in Earth’s past is complicated by simultaneous motions due to plate tectonics. Debate has surrounded the existence of Late Cretaceous TPW ca. 84 million years ago (Ma). Classic palaeomagnetic data from the Scaglia Rossa limestone of Italy are the primary argument against the existence of ca. 84 Ma TPW. Here we present a new high-resolution palaeomagnetic record from two overlapping stratigraphic sections in Italy that provides evidence for a ~12° TPW oscillation from 86 to 78 Ma. 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.

[…]

Mitchell et al,. 2021

The full text of the paper is available and well-worth reading.

True Polar Wander is a real thing and probably occurs at an average rate of 1°/Ma (Andrews, 1985). Mitchell et al., 2021 have found “evidence for a ~12° TPW oscillation from 86 to 78 Ma”… 12° over 8 million years is about 1.5°/Ma.

Figure 3 from Mitchell et al., 2021. “Reconstruction at 80 Ma, centered at 10°E palaeolongitude, showing globally averaged palaeopoles72 (green) exhibiting oscillations interpreted as earlier Mesozoic TPW events22. Italy and its new poles (yellow) reconstructed using Euler parameters (4.0°N, 32.6°W, 21.8°CW) in a global plate model with simplified Mediterranean motions guided by ref. 71. All Italian poles are from Apiro except 85 and 84 Ma from Furlo that fill the gap at Apiro (Supplementary Fig. 2). Error ellipses are projections of cones of 95% confidence interval. Present-day TPW axis (minimum moment of inertia, Imin) at 0°N, 10°E and orthogonal plane of TPW in red425. Note consistency of TPW longitude in all datasets. Supplementary Data 3 for palaeopoles.”

12° is just 78° shy of Earth tipping on its side. Mr. Nield’s headline is…

True Polar Wander: Geology vs Bad Science Fiction

It’s possible that True Polar Wander, deepened the Cenozoic ice age about 3 Ma (Woodworth & Gordon, 2018). There is even evidence of a couple of TPW episodes of >50° shifts during the Neoproterozoic Era (Maloof et al., 2006). However, there’s no evidence that Earth has tipped on its side at any point in the past 600 Ma or so. Nor is there any evidence of sudden, catastrophic events associated with TPW.

Actual geological evidence for TPW does not support the cataclysmic pole shift hypothesis, or any other Edgar Cayce/Immanuel Velikovsky/Charles Hapgood nonsense.

References

Andrews, J. A. (1985), True polar wander: An analysis of Cenozoic and Mesozoic paleomagnetic poles, J. Geophys. Res., 90( B9), 7737– 7750, doi:10.1029/JB090iB09p07737.

Maloof, Adam C., Galen P. Halverson, Joseph L. Kirschvink, Daniel P. Schrag, Benjamin P. Weiss, Paul F. Hoffman; Combined paleomagnetic, isotopic, and stratigraphic evidence for true polar wander from the Neoproterozoic Akademikerbreen Group, Svalbard, Norway. GSA Bulletin 2006;; 118 (9-10): 1099–1124. doi: https://doi.org/10.1130/B25892.1

Mitchell, R.N., Thissen, C.J., Evans, D.A.D. et al. A Late Cretaceous true polar wander oscillation. Nat Commun 12, 3629 (2021). https://ift.tt/3j0R9yd

Woodworth, D., & Gordon, R. G. (2018). Paleolatitude of the Hawaiian hot spot since 48 Ma: Evidence for a mid-Cenozoic true polar stillstand followed by late Cenozoic true polar wander coincident with Northern Hemisphere glaciation. Geophysical Research Letters, 45, 11,632– 11,640. https://doi.org/10.1029/2018GL080787

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October 27, 2021 at 08:40PM

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