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What caused the bend in the Emperor/Hawaii chain of islands, 45 million years ago?

Has there been any updates to this mystery I am unaware of? Are there any new theories that could potentially explain it?

There is a lot of material but no answer at the link provided. University of Hawaii material discussing the root cause of the pattern of formation of the Emperor and Hawaii chain of islands

an excerpt...

Perhaps it is even more amazing that in the past 65 million years there has been only one such bend. Even more remarkable is the observation that the straight portions of the chain are straight. As we shall see below, the configuration of the plate boundaries in the Pacific have changed dramatically during the lifetime of the Hawaiian hotspot. If, as many geophysicists believe, subduction drives tectonics, then how on earth can the straight parts be so straight and move at constant velocities for tens of millions of years? The answer to these questions remains a mystery!

Bend in the Emperor Hawaii chain of islands

ADDED: Sept 1st. an excerpt from a link to information in the comment below. thank you MyCarta, good information:

The bend in the Hawaiian-Emperor seamount chain is a prominent feature usually attributed to a change in Pacific plate motion approx 47 Myr ago. However, global plate motion reconstructions fail to predict the bend. Here we show how the geometry of the Hawaiian-Emperor chain and other hotspot tracks can be explained when we combine global plate motions with intraplate deformation and movement of hotspot plumes through distortion by global mantle flow. Global mantle flow models predict a southward motion of the Hawaiian hotspot. This, in combination with a plate motion reconstruction connecting Pacific and African plates through Antarctica, predicts the Hawaiian track correctly since the date of the bend, but predicts the chain to be too far west before it. But if a reconstruction through Australia and Lord Howe rise is used instead, the track is predicted correctly back to 65 Myr ago, including the bend. The difference between the two predictions indicates the effect of intraplate deformation not yet recognized or else not recorded on the ocean floor. The remaining misfit before 65 Myr ago can be attributed to additional intraplate deformation of similar magnitude.

I don't know if that is definitive or not?

I have come across this image showing the lately determined "pattern of expansion" the earth is undergoing: perhaps then the quote above is indicating a "perceived balance caused in the expansion as correctly predicting and matching the movement of the plume and plates relative to the pattern?

Pattern of overall tectonic plate expansion

****UPDATE Sept 24th -- Information from MyCarta**

MyCarta "I think the more recent research leans towards a combination of intraplate deformation and movement of the plume itself, combined with the plate motion, e.g."

And about Euler plates, and Lord Howe's Rise

http://www.earth.northwestern.edu/people/seth/demos/BRICK/brick.html

as added in a comment below, quoted from the paper's abstract:

if a reconstruction through Australia and Lord Howe rise is used instead, the track is predicted correctly back to 65 Myr ago, including the bend.

From the first paragraph in the paper:

Hotspots are frequently assumed to be fixed and used as a reference frame for plate motions. However, when the Hawaiian hotspot track is predicted from a global plate motion chain based on relative plate motion data, and it is assumed that the Hawaiian hotspot is fixed relative to African hotspots, it does not fit the observed track: the predicted track is essentially straight, lies south of the Hawaiian seamount chain, and has no feature corresponding to the Hawaiian-Emperor bend. Explanation of this misfit requires one of the following, or a combination of them, to be true: (1) motion of Pacific plate hotspots, in particular more than 1,000 km south-westward motion for the Hawaiian hotspot between ,80 Myr ago and the time of the bend and minor southward motion after this time, (2) motion of hotspots in the African hemisphere, (3) motion at an additional plate boundary, or (4) deformation at a diffuse intraplate boundary not included in the plate motion chain. Palaeomagnetic data from the Emperor chain3 yield a southward component of Hawaiian hotspot motion more than 1,000 km relative to the palaeomagnetic axis between ,80 and 49 Myr ago.

In the rest of the paper they used 2 main models (other models were discarded). The first included only hotspot motion which is sufficient to explain discrepancies between predicted and observed hotspot tracks (e.g. Hawaiian-Emperor chain) back to 47 Ma ago, but before 47 Ma ago the predicted hotspot tracks do not include the bend. Their second model added intraplate deformation (in their reference plates Antarctica/New Zealand) to hotspot motion and is able to predict the hotspot track all the way back to 65 Ma ago with good accuracy, including the bend, and with less accuracy (meaning that it is off too far to the west) until 85 My ago."

Sept 24th MORE QUESTION

I'm getting the feeling tectonic plate heave and settle and patterns of interaction are the current best theory for the resulting relative motion of the Hawaii hotspot.

So we are increasing the scale of the question to ask what is it that drives the schedule of the tectonic plates, such that the result is the ever so slow motion of the Hawaii hotspot. What is felt to be the root cause of timing of plate and continent shift??

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    $\begingroup$ Even the mechanism to how the Emperor Island chain is hotly debated, a definitive answer to the "bend" would likely result in a very high impact publication. $\endgroup$ – Neo Aug 28 '14 at 7:08
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    $\begingroup$ Hi Alistair, it would be nice if you choose my answer, if you liked it. Your September 24th update is definitely worth a new question, although it is a bit generic and you may want to give it a bit of substance and focus. $\endgroup$ – MyCarta Sep 25 '14 at 15:03
  • $\begingroup$ Having said that, there's plenty in the reference material provided to get started. The main driver is without question mantle convection, regardless of wether hot spots are stationary or not, and wether plates deform or not. in the 2009 Tarduno et al. paper I referenced there's quite a bit on that. $\endgroup$ – MyCarta Sep 25 '14 at 15:05
  • $\begingroup$ Although I suggest going back and doing some serious, in-depth reading on plate tectonic itself. I really recommend working the Cox and Hart book front to back. You will work out all the details of both theory and practice of it, with pencil, paper an scissors, or a computer if you're into programming (all formulations are already worked out in the book and one only nead to transfer them to Python, Matlab, or power calculator). $\endgroup$ – MyCarta Sep 25 '14 at 15:13
  • $\begingroup$ One more thing to bear in mind: we stil ldo not know all about the why and the timing. It's to answer these questions that the Caltech Tectonic Observatory was created. Check them out, they're awesome. I'm outta here. :) $\endgroup$ – MyCarta Sep 25 '14 at 15:15
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I don't recall this being considered a real 'mystery'. For decades after Tuzo Wilson's revolutionary Plate Tectonics the accepted explanation was of a change in direction in the plate motion over the mantle plume. I am pretty sure this was still the case when I read Plate Tectonics: How It Works (by Cox and Hart, Wilson's former students - I encourage you to get the book and work through it, you get to do plate tectonic reconstruction yourself, with paper and pencil, and calculator) in the late nineties. I think the more recent research leans towards a combination of intraplate deformation and movement of the plume itself, combined with the plate motion, e.g.

Prediction of Emperor-Hawaii seamount locations from a revised model of global plate motion and mantle flow by Steinberger et al. (Nature 430, 167-173, 8 July 2004) http://www.nature.com/nature/journal/v430/n6996/abs/nature02660.html

UPDATED: as added in a comment below, quoted from the paper's abstract:

if a reconstruction through Australia and Lord Howe rise is used instead, the track is predicted correctly back to 65 Myr ago, including the bend.

From the first paragraph in the paper:

Hotspots are frequently assumed to be fixed and used as a reference frame for plate motions. However, when the Hawaiian hotspot track is predicted from a global plate motion chain based on relative plate motion data, and it is assumed that the Hawaiian hotspot is fixed relative to African hotspots, it does not fit the observed track: the predicted track is essentially straight, lies south of the Hawaiian seamount chain, and has no feature corresponding to the Hawaiian-Emperor bend. Explanation of this misfit requires one of the following, or a combination of them, to be true: (1) motion of Pacific plate hotspots, in particular more than 1,000 km south-westward motion for the Hawaiian hotspot between ,80 Myr ago and the time of the bend and minor southward motion after this time, (2) motion of hotspots in the African hemisphere, (3) motion at an additional plate boundary, or (4) deformation at a diffuse intraplate boundary not included in the plate motion chain. Palaeomagnetic data from the Emperor chain3 yield a southward component of Hawaiian hotspot motion more than 1,000 km relative to the palaeomagnetic axis between ,80 and 49 Myr ago.

In the rest of the paper they used 2 main models (other models were discarded). The first included only hotspot motion which is sufficient to explain discrepancies between predicted and observed hotspot tracks (e.g. Hawaiian-Emperor chain) back to 47 Ma ago, but before 47 Ma ago the predicted hotspot tracks do not include the bend. Their second model added intraplate deformation (in their reference plates Antarctica/New Zealand) to hotspot motion and is able to predict the hotspot track all the way back to 65 Ma ago with good accuracy, including the bend, and with less accuracy (meaning that it is off too far to the west) until 85 My ago.

UPDATED SEPTEMBER 17 2014 The 2004 Nature paper still holds to fixed photspots. It invokes plate circuits (the models I referred to) and intraplate deformation.

Following my comments on September 16th, a google search for "bent Hawaiian-Emperor hotspot" returned a 2009 Science article which instead invokes hotspot motion: The Bent Hawaiian-Emperor Hotspot Track: Inheriting the Mantle Wind by John Tarduno et al. Science 3 April 2009 (Vol. 324 no. 5923 pp. 50-53).

Abstract at: http://www.sciencemag.org/content/324/5923/50.

There's a copy of the pdf article at: http://www.mantleplumes.org/WebDocuments/Tarduno2009.pdf

and a good online animation at: http://www.earthmodels.org/publications/science-2009

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  • $\begingroup$ my understanding is that doesnt explain the motion of the location of the plume itself. I think. ??? and I am unable to find any explanations that are accepted.??? $\endgroup$ – Alistair Riddoch Sep 1 '14 at 11:51
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    $\begingroup$ I quote Neo from a comment to the original question... "a definitive answer to the "bend" would likely result in a very high impact publication." $\endgroup$ – Alistair Riddoch Sep 16 '14 at 23:36
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    $\begingroup$ Question/hint for you: what do you think would happen to the reconstructed motion if the plate where the pole is located, instead of being stationary, also moved? And then what if it also went through a stage of internal deformation (shrinking, expanding, rotating, you name it)? $\endgroup$ – MyCarta Sep 17 '14 at 2:07
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    $\begingroup$ Or if the pole itself was not stationary, but every so often it jumped position? $\endgroup$ – MyCarta Sep 17 '14 at 3:05
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    $\begingroup$ Just to weigh in, that most of the disagreement here comes from the fact that we know very little about mantle plumes and hotspots, but I think that this is close to the best contemporary answer as possible- well done MyCarta! $\endgroup$ – Neo Sep 17 '14 at 18:12
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At the time the bend occurred, the earth had a different angle of rotation. Look east of NZ, follow faults in the floor of the pacific and other places, seamount chains etc. Think extinction times, biblical reference to the sun stopping or going backward etc. Whether the result of an asteroid strike, or just a rotational wobble, it explains a lot. The Emporer chain, much of which has now gone under, shows the original line of rotation. The Hawaiian chain the new angle of rotation.

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    $\begingroup$ Extraordinary claims require extraordinary evidence $\endgroup$ – Jan Doggen Apr 10 at 13:09
  • $\begingroup$ The end happened tens of millions of years ago. Humanity came on the scene within the past few hundred thousand years. The bible is about 2,700 years ago. It seems, to say the least, unlikely that the bible can provide any hints or clues as to the cause of the bend in the Emperor/Hawaii chain. $\endgroup$ – Alistair Riddoch May 4 at 11:19

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