Earth's birthday and going into a new world age cycle

by mind blown 23 Replies latest jw friends

  • mind blown
    mind blown

    I do notice my mother getting more delusional and or agitated during a full moon period, and at times I can't sleep due to the engery. So call me out off my rocker. ok.

    Sorry for the error of the eclipse Cofty. However, it was a lot colder here that day.

    And thank you for the info you posted from Wiki:

    There is evidence of precession and changes in axial tilt, but this change is on much longer time-scales and does not involve relative motion of the spin axis with respect to the planet. [citation needed] However, in what is known as true polar wander, the solid Earth can rotate with respect to a fixed spin axis. Research shows that during the last 200 million years a total true polar wander of some 30° has occurred, but that no super-rapid shifts in the Earth's pole were found during this period. [ 2 ] A characteristic rate of true polar wander is 1° per million years or less. [ 3 ] Between approximately 790 and 810 million years ago, when the supercontinentRodinia existed, two geologically-rapid phases of true polar wander may have occurred. In each of these, the magnetic poles of the Earth shifted by ~55°. [ 4 ]

    Driving forces related to Earth rotation

    Alfred Wegener, being a meteorologist, had proposed tidal forces and pole flight force as main driving mechanisms for continental drift. However, these forces were considered far too small to cause continental motion as the concept then was of continents plowing through oceanic crust. [ 20 ] Therefore, Wegener converted to convection currents as the main driving force in the last edition of his book in 1929.

    In the plate tectonics context (accepted since the seafloor spreading proposals of Heezen, Hess, Dietz, Morley, Vine and Matthews (see below) during the early 1960s) though, oceanic crust is in motion with the continents which caused the proposals related to Earth rotation to be reconsidered. In more recent literature, these driving forces are:

    1. Tidal drag due to the gravitational force the Moon (and the Sun) exerts on the crust of the Earth
    2. Shear strain of the Earth globe due to N-S compression related to the rotation and modulations of it;
    3. Pole flight force: equatorial drift due to rotation and centrifugal effects: tendency of the plates to move from the poles to the equator ("Polflucht");
    4. Coriolis effect acting on plates when they move around the globe;
    5. Global deformation of the geoid due to small displacements of rotational pole with respect to the Earth crust;
    6. Other smaller deformation effects of the crust due to wobbles and spin movements of the Earth rotation on a smaller time scale.

    For these mechanisms to be overall valid, systematic relationships should exist all over the globe between the orientation and kinematics of deformation, and the geographical latitudinal and longitudinal grid of the Earth itself. Ironically, these systematic relations studies in the second half of the nineteenth century and the first half of the twentieth century do underline exactly the opposite: that the plates had not moved in time, that the deformation grid was fixed with respect to the Earth equator and axis, and that gravitational driving forces were generally acting vertically and caused only locally horizontal movements (the so-called pre-plate tectonic, "fixist theories"). Later studies (discussed below on this page) therefore invoked many of the relationships recognized during this pre-plate tectonics period, to support their theories (see the anticipations and reviews in the work of van Dijk and collaborators. [ 21 ]

    Of the many forces discussed in this paragraph, tidal force is still highly debated and defended as a possible principle driving force, whereas the other forces are used or in global geodynamic models not using the plate tectonics concepts (therefore beyond the discussions treated in this section), or proposed as minor modulations within the overall plate tectonics model.

    In 1973 George W. Moore [ 22 ] of the USGS and R. C. Bostrom [ 23 ] presented evidence for a general westward drift of the Earth's lithosphere with respect to the mantle, and, therefore, tidal forces or tidal lag or "friction" due to the Earth's rotation and the forces acting upon it by the Moon being a driving force for plate tectonics: as the Earth spins eastward beneath the moon, the moon's gravity ever so slightly pulls the Earth's surface layer back westward, just like proposed by Alfred Wegener (see above). In a more recent 2006 study, [ 24 ] scientists reviewed and advocated these earlier proposed ideas. It has also been suggested recently in Lovett (2006) that this observation may also explain why Venus and Mars have no plate tectonics, since Venus has no moon and Mars' moons are too small to have significant tidal effects on Mars. In a recent paper [ 25 ] it was suggested that, on the other hand, it can easily be observed that many plates are moving north and eastward, and that the dominantly westward motion of the Pacific ocean basins derives simply from the eastward bias of the Pacific spreading center (which is not a predicted manifestation of such lunar forces). In the same paper the authors admit, however, that relative to the lower mantle, there is a slight westward component in the motions of all the plates. They demonstrated though that the westward drift, seen only for the past 30 Ma, is attributed to the increased dominance of the steadily growing and accelerating Pacific plate. The debate is still open.

  • Leolaia

    From the Wikipedia reference:

    Polar wander should not be confused with precession or nutation, which is where the axis of rotation moves, in other words the North Pole points toward a different star. These are caused by the gravitational attraction of the Moon and Sun, and occurs all the time and at a much faster rate than polar wander. It does not result in changes of latitude.

    True polar wander has to be distinguished from continental drift, which is where different parts of the Earth's crust move in different directions because of circulation in the mantle.

    The effect should further not be confused with the effect known as geomagnetic reversal that describes the repeated proven reversal of the magnetic field of the Earth.

    These four separate things, which are unrelated to each other, should not be conflated as is often done in unscientific popular writing.

    And these occur at a very slow time scale, not catastrophically, involving thousands (geomagnetic reversal), tens of thousands (precession cycle), or millions of years (continental drift and polar wander); the exception would be a massive asteroid or planetary impact, such as what is hypothesized as occuring in the case of Uranus's axial shift.

  • mind blown
    mind blown

    Thank goodness for that! I wouldn't want to have to deal with a polar wander in my life time. But at least I'll be able go on into a new world age (according to the Mayans)

  • Twitch

    Too bad the Mayans didn't see the Spanish coming...

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