“The Earth’s inner core is rotating faster than the rest of the planet, scientists have found. An ingenious comparison of earthquakes has revealed that the solid ball of iron and nickel at the centre of the planet is spinning about half a degree more quickly than its upper layers. While the excess spin is very small, it means that over 900 years the very centre of the Earth will complete one more revolution than the rest.


The findings settle a scientific controversy that has raged for nine years, since Professor Paul Richards, of Columbia University in New York, and Professor Xiaodong Song, of the University of Illinois at Urbana-Champaign, first proposed the core’s odd behaviour.
Their 1996 study was widely disputed, with many researchers suggesting that the apparent extra spin was in fact caused by measurement errors.
While the core is poorly understood — the great physicist Richard Feynman once said we know more about the centre of the Sun than the centre of the Earth — it is critical to the make-up of the planet, and indeed to life on Earth. Currents in the core create a vast dynamo that generates the planet’s magnetic field. Without this, the surface would be exposed to radioactive cosmic rays and plasma from solar flares that would make the existence of complex life all but impossible.
In the new study, details of which are published in the journal Science, a team led by Professor Song and Professor Richards made use of earthquakes in the South Sandwich Islands, in the Pacific Ocean.
Two earthquakes, in 1993 and 2003, occurred no more than half a mile apart and generated precisely the same patterns of peaks and troughs on seismographs thousands of miles away in Alaska. The seismic waves from the 2003 earthquake, which passed through the Earth’s core, arrived at the Alaska monitoring station about a tenth of a second more quickly than they did in 1993. Only an inner core spinning faster than other parts of the Earth can explain this.
The most likely explanation is electromagnetic coupling, the phenomenon that drives electric motors. “The magnetic field generated in the outer core diffuses into the inner core, where it generates an electric current,” Professor Song said. “The interaction of that current with the magnetic field causes the inner core to spin.”
So – the earth is composed of three layers, the mantle, the outer core and the inner core.
“No one can really explore the earths interior. Scientist obtain information about the characteristics of the earth's interior by studying earthquake records. Earthquake waves help scientists figure out the distances to each of the section of the earth's interior. The Earth can be divided into three large sections: the mantle, inner core, and outer core. The inner core is at the center of the earth. The pressure and temperature of the earth increases as one moves closer to the center. First comes the mantle, this is a layer that is bellow the crust of the earth. This is said to go down 2,900 kilometers; it's temperature is about 870 degrees Celsius. The outer core has a very high temperature and ranges from about 4,400 degrees Celsius to about 6,100 degrees Celsius. The outer core begins where the mantle stops and it extends further down to the center 2,250 kilometers. The inner core is about 6,400 kilometers below the earths surface. the temperature at the inner core of the earth is at about 7,000 degrees Celsius.

The inner core is a molten ball of iron and nickel and is believed to be rotating within the outer core.
This rotating action of the inner core within the outer is believed to be creating the Earth’s gravitational field
It is believed that the inner core is drawing iron from the outer core and mantle through a process that is described below:
“The Earth’s upper mantle is mostly made up of silicon oxide or “silicate” and a mixture of iron and magnesium oxide. At high temperatures, a metallic melt containing iron forms between grains of the silicate crystals because it has a lower melting point. For this metal to form a planetary core, it must separate from the silicate matrix and move through it (figure 2).
Tomoo Katsura and colleagues measured the electrical conductivity of the silicate and iron melt at temperatures of 1300oC and pressures of 3 gigapascals. These conditions correspond to those found about 100 km below the surface of the Earth. The conductivity of iron compounds is much larger than that of silicates, which allows small amounts of the metal alloy to be detected.
The researchers found high conductivities in their samples – corresponding to about 6% by volume of iron melt - which remained even after the temperature was reduced. The molten iron creates “connective” channels in the silicate allowing the metal to separate out.
The high temperatures needed to melt the iron may have come from the heat released from the radioactive decay of short-lived isotopes that were present in the early Solar System. If the high conductivities observed in the experiment correspond to the flow of metal through the silicate, then the separation of core from mantle could have occurred very quickly – in less than 3 million years - in small planetisimals with radii of less than 30 km.”
So, iron within the Earth’s mantle and outer core is being siphoned into the inner core. So what fills the spaces left behind?
Secondly, it is generally believed that a nuclear reaction is taking place at the earth’s core. This nuclear reaction is largely responsible for the heat being generated which is maintaining the core in a molten state.
Thirdly, the inner core is believed to be rotating within the outer core and behaving like a gigantic electrical generator creating a magnetic field which in effect is the earth’s gravitational field.
However, in an electrical generator there is an air gap between the rotating coil and the stator coil that induces the magnetic field . This gap has to exist for a magnetic field to be created. So is there a gap between the inner and outer core and can that gap gradually increase over time due to material loss to the point where a collapse has to occur in order to maintain the electromagnetic process?
Conclusion: we know that the inner core draws Iron from the Earth’s outer core and mantle. Is this material vital to the nuclear reaction at the core and does this action weaken those layers?.
The molten iron/nickel core is maintaining its molten state largely through a nuclear process, a nuclear process that has to be consuming surrounding material as fuel and through a process of vaporisation. Is this action creating a gradually increasing gap between the inner and outer cores.? A gap that increases to the point where a collapse occurs which results in a cataclysmic change in the earth’s mass and; through crust displacement, the distribution of its land mass.

“Where did all the water on Earth came from? This is a particular problem for planetary scientists because the Earth simply should not have the amount of water that it does. The Earth is relatively close to the Sun, and water, a volatile, should have been expelled from the early inner solar system before the Earth formed. As such, the Earth should really be a much drier planet. So where did all the water that is so crucial to the biosphere of this planet originate?
Up until recently the leading theory was the notion that the oceans were deposited by comets impacting the newly formed Earth This bombardment occurred over a billion years (and might also explain how life appeared on Earth so early in its geo-history). Recent data from comets has overturned this possibility. The problem is that the isotopic ratios of terrestrial water and cometary ice are quite different.
The comets analysed thus far contain relatively large quantities of deuterium, yet this isotopic form of water is rare on Earth. If this composition of known comet ice is representative of solar system comets in general, then very little of the Earth’s water can be attributed to cometary impact following the Earth’s formation. Taking this into account, it appears that only half of the Earth’s oceans could have been deposited by impacting comets.
Current theories of the formation of the Moon are centred upon a massive collision between the early Earth and a Mars-sized body, scattering debris into orbit around the Earth, which eventually coalesced to form the moon. The lack of a significant iron core within the Moon suggests that this impact took place after the Earth’s own iron core had already gravitated to the centre of our planet It’s conceivable that the remainder of the early Earth’s scattered debris formed the asteroid belt, and this possibility is readily testable by further scientific study of the composition of asteroids within the belt between Mars and Jupiter. This might have occurred when the Moon formed, or as a result of later impacts upon the recovering Earth.
“If correct, then the primordial Earth must have been a very large planet indeed, such that major impacts upon it created both the asteroid belt and the Moon (but clearly not the comets). Such a massive terrestrial planet could have readily held onto a vast amount of water. It also would not be so incongruous that the larger primordial Earth would have hosted such a massive satellite as our Moon.”

If the Earth was involved in a collision how is it round surely it would shaped alot differently?

and

also if it was an odd shape it would not spin on an axis?

an excellent question sir. You have completely destroyed my theory.

The reason the Earth is "round", well actually it's oval shaped, is because of the atmosphere surrounding the water and land. I'm not a techy person, but I believe the swirling gases in the atmosphere help fortify the innate shape of the planet. Earth has been struck by space debris and metorites for eons and it has kept its shape. Even violent volcanic eruptions and earthquakes hasn't altered the circumference of the planet, only the surface.

The reason the Earth is round is because where objects become massive enough to actually exhibit a decent amount of gravity, the force of gravity, pulling all of the planet's mass towards towards the center of the body, pulls it into a round shape. You can see this in the asteroid belt, where tiny asteroids are as irregular as they can be, but giants like Ceres (900 mile across) are sphere-like.

It's also worth remembering that the theoretical collision between Earth and another object, that resulted in the formation of the Moon, occured something like 4,500,000,000 years ago.......

this phrase alone makes me question the legitimacy of the author. where did you find this, fantazum?

Summary (Aug 31, 2005): Scientists at Columbia University's Lamont-Doherty Earth Observatory and the University of Illinois at Urbana-Champaign have ended a nine-year debate over whether the Earth's inner core is undergoing changes that can be detected on a human timescale. Their work, which appears in the August 26 issue of the journal Science, measured differences in the time it took seismic waves generated by nearly identical earthquakes up to 35 years apart to travel through the Earth's inner core.

http://www.astrobio.net/news/article1696.html

thank you fantazum. the one bit was likely a typo, i think they meant "magnetic field"

the earth may have been bigger before the collision for two reasons:

it was partially molten (less dense, but the same mass, this also explains why the earth has its mostly round shape today)

it may have lost some mass in the impact.

as far as the iron core goes, silicates are less dense than iron, and will therefore "float" while the iron "sinks". it is also less conductive. i'm not much of an authority on electromagnets, but must the gap be air, or can it be any non-conductive material? i may have to build one and experiment with it...

also, anything that happens within the earth system would not change its mass, as per the conservation of matter.

boy, that's a long post. hard to take in all at once for responses! pardon my scatterbrainedness, i can't even use real words today

in a mechanical electrical generator or motor there is an air gap between the rotor and stator. This gap is necessary in a mechanical device but may not be necessary at the arth's core....so you make a good point. Some other material may take the place of the air gap.
Many scientists believe that during the period of the larger dinosaurs the oxygen content of the air was higher which might explain how these creatures attained such great size. More oxygen means a smaller heart muscle but there are still physiological problems particularly with bone structure and especially at the hip joints where the greatest stress occurs. Even with increased oxygen supply the physical weight of the creature remains the same. If the leg bones were solid and not hollow as some believe and muscular development was greater than we at present estimate....then the creatures may indeed have been able to support their own weight easily under gravitational conditions similar to those prevailing now.
the only remaining question is; how could such large numbers of these gigantic creatures have found sufficient food to sustain themselves? If the earth was pretty much the same size it is today with about the same amount of land area, a lot of which would have been desert and pole; then given the daily food intake of one of the larger sauropods multiplied by perhaps 5 million (conservative estimate)........again- all I can see is mass extinction thru simple starvation within a few generations.

the bones of the big guys were not hollow as far as we have seen from well preserved specimens. also, we have to consider that bones themselves are relatively light, but fossilized bones are often not.
the oxygen content may have been higher, i will have to do some research on the abundance of oxidized cenzoic formations.
as for finding food, it is actually not that difficult. large creatures such as elephants travel in herds and only have trouble when humans intervene. basically, if a hungry animal is not very picky about its food, there's plenty to go around. dinosaurs were abundant, but the true big guys were a little less frequent. most dinosaurs were quite small, ranging from mouse-size to dog-size. but watch the feeding patterns of elephants that live in arid climates, and you'll see what i mean about it not being too difficult to find food.

I have read and understood most of this. I wonder, though, how do we know where our water came from, and how is it we have more than we should?

This is the question burning in my mind right now.

many scientists are asking the same question. The fact that the earth does have a disproportionate amount of water on its surface....an anomaly which of course was one of several anomalies that motivated me to ask the question: was the earth a larger planet when the great dinosaurs roamed it?

The earth began its life as a gaseous ball, this gas cooled and solidified forming the earth's crust,the mantle, the outercore and the inner core. The inner core is believed by some, to be still molten.
Occasionally there have been catalclysmic seismic upheavals caused by what we dont know.But they have definitely taken place and they have been of such magnitude that the earths crust has liquified and folded. These events may be takling place at regular intervals of 20 -30 million years.
Could these upheavels be a result of the earth actually collapsing upon itself? Could the nuclear reaction taking place at the core be using material from the outer core,mantle and crust to fuel it, thereby creating weaknesses in those layers that eventually cause a collapse? If such an event was indeed taking place at regular times then the chemical cocktail of gasses that they emit into the atmosphere could be creating the water that now covers three fifths of the planet's surface.

I have suggested that the earth was larger and less dense therefore gravity was less which allowed dinosaurs to grow to sizes which would be impossible under earth's present gravitational force. Dinosaurs that weighed up to 150 tons with necks 70 feet in length that alone weighed something like 40 tons. They simply could not support their own weight.
And of course, it is ludicrous to beleieve that these creatures existed in their millions isnt it?....well they MUST have because they were on this earth for 150 million years. They were the most successful of all of the species that have lived on this planet

To sum up: during the period of the great dinosaurs was the earth bigger? was its density less? was gravity less? is this planet subject to a gigantic seismic upheaval every 20 or 30 million years - an event that occurs like clockwork?

They were able to carry their enormous weights because of the structures of the bodies. Here's a link to how Sauropods (like Brachiosaurs, and the like) were able to support themselves.

This is a testable theory, I guess. Depending on whether you know the types of chemical reactions that produce water, and whether the conditions for these reactions could have plausibly existed in the proto-earth's outer and inner core and mantle. That's a starting point, anyway, I'm not much with chemistry or geology.

As for the rest, I have doubts. If these dramatic upheavals happen every 20 or 30 million years, we would have had at least one other worldwide cataclysm since the dinosaurs died out. As far as I know, the geologic record shows nothing on that scale between the event that wiped out the dinosaurs and now. Well, we've had an ice age, but even that didn't see the wholesale loss of species that we see happen to the dinosaurs.

Dinosaurs grew to such immense sizes to take advantage of the habitat they were in at the time. I think that's about the best way I can think to put it.

yes Ive read that link before and the idea doesnt work. The cantilever theory is fine until you estimate the tension in tons per square inch thru the tendon and the stresses placed on the backbone, plus the fact that orthodox paleontologists believe that several of the larger sauropods could stand on their hind legs and extend their necks to the vertical.
Also, it is believed that these creatures were quite agile and could even run. Such rapid movement would put enormous stress of hip joints, plus the fact that creatures of such weight would have to avoid soft ground. Thier muscular structure was not so developed as to give them the enormous extra strengh to extricate themselves from very boggy ground.
No it doesnt make sense.

I think it makes sense. Dinosaurs were quite a bit more advanced than you give them credit for.

well firstly, there have been several gigantic seismic events since the end of the dinosaur age. Events large enough to have caused mass extinctions. The most recent was just previous to the melting of the second to previous ice age circa 20,000 bc. The world was rocked by a series of massive volcanic eruptions which may have precipitated a rapid melting of the ice sheets. These events of course could be reducing in size as the density of the planet increases.
And secondly, you say that dinosaurs grew to such immense sizes to take advantage of their habit.....well yes of course. We are all shaped by our environment and the environemtn during the age of the dinosaur not only allowed creatures to grow to gigantic size but also the flora.

I can see where you're going with this, and I can't say I disagree. But I still don't think there has been an extinction as massive and sudden as the one that killed off the dinosaurs. I mean, small populations of pygmy mammoths survived until as recently as a few thousand years ago.

Of course I could be completely wrong.

It depends on how you define 'agile' and 'run'. I've never read anything that suggested these creatures could move at anything more than a sort of walking stride. Moreover, we're not talking about them walking on two legs; only standing up on two legs in one place in order to mount a female.

Nonetheless, the cantilever system wouldn't have been suggested if it didn't hold water in supporting the estimated body weight of the Sauropod; i.e., they didn't just decide 'hey, that probably works!' and go with it. It is certainly more simple than a completely unproven theory on how the Earth somehow either gained significant mass or loss significant volume, without either some outside body adding enough mass to significantly increase gravity (which would only be possible through a massive impact that would kill almost all life down to the cellular level), or the Earth somehow shrinking (which would release a signicant amount of gravitational potential energy along with the radioactive heat currently produced, and screw with all known continental drift models).

well firstly, I must emphasise that Im expressing ideas here and not fixed opinions. Nature will always find a way (as some famous film character once said) so yes, I have no doubt that nature really could have allowed such gigantic creatures to exist within an environement similar to our own. But alas I am only human therefore must question.

I thought you said that the problem emerged when you calculate the tension on the vertebrae. Why don't you do some of the calculations, and post them? I'm pretty sure that it is possible to find the estimated weight of any one of a variety of Sauropods, or even better constructed creatures like an Allosaurus.

ah ha...you're trying to ambush me. despite the enormous number of theories re the weight and structure of dinosaurs in reality not a great deal is known about them. We are not even sure if all the dinosaurs were even egg layers or if they were endotherms or ektotherms. the largest of these creatures might have weighed something like 190 tons - in our gravity - but we dont really know, we just look at the size of the thing and subconsciously make a comparison with an elephant and its body mass.
and there are quite a few scientists out there who even question whether dinosaurs were animals at all.

Not at all. Although there is, of course, a lot of speculation, there are also good educated guesses out there on how heavy a sauropod was, based on the skeleton. Brachiosaurus are estimated to have weighed in at about 70 tons a piece. It should be possible, then, to do at least a rough calculation on how much weight was put on those vertebrae.

dinosaurs were most definitely egg layers!! look at all the eggs that have been found with baby dinos still inside!
Dino Eggs
and
More Dino Eggs
and who questions whether or not they were even animals? i'm looking for names here. credibility must be established to make a statement like that.

this is an interesting question. I dont believe that the larger dinosaurs were egg layers or even reptiles. I suspect they were an intermediate species having both reptilian and mammalian features.
I just cannot imagine a dinosaur weighing some 100 tons plus being an egg layer. For one thing a creature of that size would have to be a constant feeder unless of course it was omniverous and could eat meat....but their jaw structure and teeth dont point to this. So if it was a plant eater exclusively then it had to feed constantly so it simply could not afford to spend lengthy periods of time incubating an egg.

How the hell can scientists know that the core spins faster than the upper layers?

Fantazum, this is an interesting idea. I had exactly the same idea, but based on another point of vue, that of physics. I am very glad that people interested in other disciplines can come to the same "conclusion". As you must know, the hypothesis of non-constant diameter of the Earth must have influences in all sciences, meaning astronomy, geography, physics, geology, climatolgy,etc...,and paleontology. The most common "theory" you can find is that of the "expanding earth". I will not debate about this. The other one, is the shrinking Earth. In each circumstance, either the expanding or the shrinking Earth, the result of the "theory' must create the image of a "scene" acceptable in all sciences, and corresponding on what we are observing today. I have a strong feeling that the shrinking Earth is the good one. There are plenty of reasons, I will expose in another thread, if you are still there.
Friendly.
Michel. (say Mike, no Michelle)