6
   

Molten 'Jet Stream' Deep Inside Earth

 
 
Reply Sun 15 Sep, 2019 01:29 pm
Molten 'Jet Stream' Discovered Deep Inside Earth
Read more at https://www.geologyin.com/2016/12/molten-jet-stream-discovered-deep.html#Q2fftEvdJ6EUPHWh.99
  • Topic Stats
  • Top Replies
  • Link to this Topic
Type: Discussion • Score: 6 • Views: 662 • Replies: 27

 
roger
 
  1  
Reply Sun 15 Sep, 2019 02:12 pm
@edgarblythe,
Interesting.
farmerman
 
  2  
Reply Sun 15 Sep, 2019 04:13 pm
@roger,
Three scientists , two from US and one from Canadia working on sea floor spreading and subduction, speculated on the variable rates of circulation of the various mantle layers about the core, and they posited, back in 1965 or so, the variable rates an what the SWARM sat data shows is that they werent too far off.
georgeob1
 
  1  
Reply Sun 15 Sep, 2019 04:35 pm
@farmerman,
Similar observations, perhaps not as precise, have been made based on observed fluctuations in the earth's magnetic field, based on observed fairly rapid local variations in the magnetic variation ( the compass difference between true North (earth's rotational poles) and magnetic north ( magnetic poles). Some have speculated that large continuing regional trends suggested a possibly evolving bifurcation in the earth's magnetic field. This of course is but an empirical speculation, and the real origin of the earth's magnetic field lies in the circulation of molten charged iron beneath the earth's mantle.

If I'm not mistaken the ocean floor spreading data indicates about 168 reversals of the earth' magnetic polarity in the geological record. Not much is known about the details and time required for these reversals, but as prolonged period with a weakened or multipolar magnetic field could yield large and dangerous increases in solar radiation.
Below viewing threshold (view)
farmerman
 
  2  
Reply Mon 16 Sep, 2019 08:24 am
@georgeob1,
I had a student who did an MS thesis on polarity Normal v. reversal dates and evolution/extinction bursts. It was a good piece of work based solely on stats and +/- time overlaps. It was based on 184 norm/reverse periods beginning with Brunhes and going back as far as the end of the Cretaceous. (Its really a bitch going back farther because continental drift and mountain building has smeared out a lot of the record. Some guys try though. When you dont hav to work for a living like us, you can count spaces in parking lots (My comment to my nephew who chose academeia for his lifs work)
JTT
 
  -4  
Reply Mon 16 Sep, 2019 09:28 am
@farmerman,
I pity any "student" who "studied" under you, farmer. Teachers never deny reality, science, evidence, ... . That is the antithesis of being a teacher.
farmerman
 
  3  
Reply Mon 16 Sep, 2019 10:23 am
@JTT,
Im sorry, the folks interested in what you have to say have left. Ill pass the word youre back.
georgeob1
 
  1  
Reply Mon 16 Sep, 2019 11:25 am
@farmerman,
Interesting. You stimulated me to do some reading on the frequency of magnetic reversals and mathematical models for the dynamo involving the sub mantle circulation of charged liquid magma. I infer the geological record indicates long extended periods with few or no polar reversals and others with such reversals occurring at periods as low as ~ 200,000 years. The circulations in question originate mostly as a result of the earth's rotation and the apparent Coriolis accelerations (in earth coordinates) that result.

The differential equations modelling the field strength and this circulation are (perhaps unsurprisingly) like the Naiver-Stokes Equations for the flow of a viscous fluid, even to the extent of an analogous "Reynolds Number' expressing, in this case, the relative magnitude of the Magnetic field force to the inertial forces affecting the flow. This suggests to me that there may well be some domains of instability in these internal magma flows , possibly involving the breakup of gross circulations into multiple vortices having the same angular momentum. In such cases the magnetic shield that directs most solar radiation to the magnetic poles would be severely diminished.

I don't know much about the geological evidence for the details of the observed polar reversals - how much time was involved before the sub mantle circulation organized itself into a coherent reversal, and what may have occurred during the interregnum.

Any suggestions for more reading?
JTT
 
  -2  
Reply Mon 16 Sep, 2019 11:59 am
@farmerman,
What until all your "students" find out just how little science/evidence/the truth means to you, farmerman.

What Professor Leroy Hulsey states, what 3000 plus architects and engineers state, ... all illustrate that you are the farthest thing from a scientist.
farmerman
 
  1  
Reply Mon 16 Sep, 2019 12:10 pm
@JTT,
wow, they know me??
JTT
 
  -2  
Reply Mon 16 Sep, 2019 12:13 pm
@farmerman,
The "scientist" FM, totally incapable of doing science/evidence/reality/... .
0 Replies
 
JTT
 
  -2  
Reply Mon 16 Sep, 2019 12:16 pm
@farmerman,
Western folks, supposedly the people of truth, justice, science, evidence, ... are incredible cowards, incredible liars, folks incredibly brainwashed, folks simply unable to face the truth. But they all excel at finger pointing,which is crucial to an effective propaganda system.
0 Replies
 
JTT
 
  -2  
Reply Mon 16 Sep, 2019 12:17 pm
@farmerman,
Quote:
wow, they know me??


What Professor Leroy Hulsey states, what 3000 plus architects and engineers state, ... all illustrate that you are the farthest thing from a scientist.

FM, the "scientist" ducks and runs.
0 Replies
 
farmerman
 
  2  
Reply Mon 16 Sep, 2019 12:30 pm
@georgeob1,
yeh, a really good one is the old classic AGU paper

LOWRIE, W. and DV Kent. 2004,Geomagnetic polarity timescales and reversal frequency regimes, , (in) CHANNELL. J.E.T., DV KENT, W.LOWRIE,J. MEERT (eds),TIMESCALES OF THE PALEOMAGNETIC FIELD: AGU Geophysical Monograph 145, American Geophysical Union, (p. 117-129).

Its a good monograph about the entire Neogene reversals that really end the Cretaceous too.


My MS candidate used theGeoscience Handbook (ed 5) for the GPTS (Geomagnetic Polarity Time Scale)..

BTW, Im not real friendly with the Eulerian ,Ive always dealt in Darcy flow in porous media. The only problem with D'Arcy is its not too able to be modeled in the Coriolis field.
It requires both a fluid AND a medium.



0 Replies
 
livinglava
 
  1  
Reply Sat 21 Sep, 2019 05:57 am
@georgeob1,
georgeob1 wrote:
This of course is but an empirical speculation, and the real origin of the earth's magnetic field lies in the circulation of molten charged iron beneath the earth's mantle.

Could the magnetic field be due not to a circulation of physical magma but instead of waves of electrical/magnetic current circulating through the magma?

Usually, I would assume that molten metal can't really align magnetically until it reaches a temperature cool enough to freeze into a lattice, but if there are currents of moving charge circulating around, wouldn't those cause electrons to align in a patterned way that results in an overall net magnetic field for the planet as a whole?

It seems more likely to me that the polarity of the planetary magnetic field can reverse due to a change in current direction than a change in magma-flow direction. I can't imagine all that heavy magma stopping and reversing flow direction.

Momentum doesn't just stop and change direction, but patterns of electrical current flowing through magma could for some reason evolve into a shape that would effectuate its own polarity-reversal, I think.
georgeob1
 
  1  
Reply Sat 21 Sep, 2019 02:30 pm
@livinglava,
Maxwell's equations provide the basic relationships between the movements of charged particles and the forced related to them and the magnetic field that results. No movement: no magnetic field.

Rotating or circular flows of viscous fluids can indeed readily break up into more complex vorticial flows in which the total angular momentum is preserved. That is the essence of turbulent flow as it affects aircraft design.
livinglava
 
  0  
Reply Sat 21 Sep, 2019 05:46 pm
@georgeob1,
georgeob1 wrote:

Maxwell's equations provide the basic relationships between the movements of charged particles and the forced related to them and the magnetic field that results. No movement: no magnetic field.

Rotating or circular flows of viscous fluids can indeed readily break up into more complex vorticial flows in which the total angular momentum is preserved. That is the essence of turbulent flow as it affects aircraft design.

The movement that causes magnetism could be oscillation. It doesn't have to involve (much) linear displacement.

Besides, if there were flowing currents of magma, how would they change direction to flip the magnetic field every so often?
0 Replies
 
farmerman
 
  1  
Reply Mon 23 Sep, 2019 04:50 am
@georgeob1,
what are you getting yourself into? Ready to begin a new math course for the folks?. Sign me up, I need a few more PDH' s to renew my license.

georgeob1
 
  1  
Reply Mon 23 Sep, 2019 10:03 am
@farmerman,
You're probably right. The fact is I remember more of the conclusions than the mathematical details of getting there. I was once very conversant with vector calculus ( inner & outer product, dell, and all that and the representation of the laws of physics in them, and in tensor format as well. Now I struggle to keep up.

I have a close friend who has been, for a long time, pursuing a revised structure for general relativity based on his view that the Lorentz transformation, based, as it is, on (1-v exp2/c exp2) exp-1 formulation, wrongfully excludes velocities greater than c ( the velocity of light). Removing this restriction does indeed resolve some of the mathematical and conceptual issues still plaguing general relativity theory. His has been an up hill struggle , likely because very few have the energy or will to go back to basic issues they have long since stopped thinking about, and the professional risks they face when looking under a rock they (and their peers) have long ignored. He had me and another friend undertake the chore of proofing his math: it turned out to be a daunting chore that forced me to wade through stuff I once knew but the details of which I had long since forgotten . He's now close to getting his work published in a Physics Journal.

By the way I'm currently reading a very insightful work by a dedicated geologist, Marcia Bjornerud, entitled "Timefulness". It's a fascinating journey through the geological perspective of science & physics starting with James Hutton's 1789 then revolutionary speculations on the age of the planet.
 

Related Topics

New Propulsion, the "EM Drive" - Question by TomTomBinks
The Science Thread - Discussion by Wilso
Why do people deny evolution? - Question by JimmyJ
Are we alone in the universe? - Discussion by Jpsy
Fake Science Journals - Discussion by rosborne979
Controvertial "Proof" of Multiverse! - Discussion by littlek
 
  1. Forums
  2. » Molten 'Jet Stream' Deep Inside Earth
Copyright © 2019 MadLab, LLC :: Terms of Service :: Privacy Policy :: Page generated in 0.03 seconds on 10/22/2019 at 04:55:28