Real Science Radio: Earth & Mercury's Decaying Magnetic Fields

[DavisBJ]

It's looking like the theory of alternating bands based on the previous band is busted unless I can come up with data consistent with the idea.

OK, Let’s keep that idea on a back burner, and we’ll pick it up again if something lending support to it comes up.

This is the reason for looking for a different explanation. The energy required to push the oceanic crust under continental crust (to say nothing of continental crust under continental crust) is just too great for the mechanism of plate tectonics to do it. The only real way to get what we see today is for the crust to get up some momentum.

Not so. Think about this. If, as science contends, the oceanic crust is formed by slow seafloor spreading, with basaltic magma slowly filling in the gap and hardening into new seafloor, then in fact the seafloor is largely of the same rock that the upper regions of the mantle are. It’s just that in the case of the seafloor, the basaltic magma has been cooled enough to harden into basaltic rock. And, basaltic rock has very slightly higher density than basaltic magma. That means we have a heavy layer floating on a lighter liquid. That is an unstable situation. In the seafloor case, the oceanic plate is a wide and rather thick sheet riding on top of an immensely viscous fluid of only slightly less density. Once something forces an edge of that oceanic plate down into the mantle, there will be an actual gravitational pull helping the dense oceanic crust to sink further down.

The density differences are very subtle, heat conduction is very slow, and the viscosity is immense. Support for this idea comes from seeing that old oceanic crust (which has had more time to cool and is therefore more dense) is seen to subduct at a steeper angle than younger crust.

And there's more. The sea floor away from the bands doesn't follow a particular magnetic direction as it should. And even more damning, the direction of the field inside the bands themselves, deeper down, should be relatively even, but it's not.

I don’t know what you mean when you say “seafloor away from the bands”. As to what the magnetic orientation of the deeper regions of the oceanic crust are, I haven’t seen any data on that. You have something specific?

Does that prove the hydroplate theory? No, but we have to find something that can actually account for the facts we see today. Plate tectonics isn't it.

Plate tectonics won a place as a credible scientific theory against a formidable amount of scientific skepticism. There sure are details that are being worked out, and questions still without answers, but there isn’t a field of science that the same can’t be said for. A (true) scientist doesn’t discard a theory at the first sign that it didn’t give ready answers to some questions. Frequently investigating the anomalies ultimately broadens and buttresses the theory.

That's just one of the many anomalies that shows plate tectonics is wrong. Something else happened.

Here you go taking something that I said I did not know (what magnetic pattern on the Pacific plate is) and decreeing that shows plate tectonics is wrong. For you to make that logical leap, you would have to have the information I said I did not have, about the magnetic characterization of the Pacific plate. Cough it up and tell me.

Problem is, the facts simply don't support a reversing dipole. We have one fact, the bands in the Atlantic, that is supposed to support a reversing field, but there is something else that has to be going on. It wasn't reversals.

What are the facts you are saying don’t support a reversing dipole? The relevant facts I am aware of are that there is a pattern of magnetic stripes on the seafloor and the seafloor is spreading slowly. Creationists (and scientists) say the earth’s magnetic field has been decreasing in strength. These facts look like something like a reversing dipole could help answer.

 

[Lighthouse]

I understand. Sometimes you (and Stripe) enjoy mocking more than meaningful dialogue. I will keep that in mind when I see you respond to a post.

I wasn't mocking; I was exasperated. I've already explained why.

 

[One Ugly Christian]

Have you guys seen: A New Scientist article reports the finding of this massive ocean(s) in "the layer of hot rock between Earth's surface and its core." It's said to be three times the volume of all the earth's oceans.

This provides massive evidence for the validity of Dr. Walt Brown's Hydroplate Theory as well as proof that yet another of his dozens of predictions has been proven true which, like most predictions by creation scientists, is exactly opposite of those by evolutionists. Predictions BTW, for those who don't know, are the acid test for scientific theories which can't be proven by direct observation. An encyclopedia could be written on predictions by evolutionists which have been proven false and another encyclopedia on those by creationists which have been proven true.

Further, even a small volume of water deep in the crust totally invalidates any theory that the earth was once a molten as water would have been forced to the surface if that were the case. The theory that the moon was formed by a collision between the earth and a Mars-sized planet 4 billion years ago, as though its not silly enough, is similarly proven false by this evidence. Water has also been found on the the moon which was supposedly formed by once molten materials floating in space. To think that water would remain in such materials for the billion years it took the moon to congeal would be---well, you'd have to be an evolutionist to belief such foolishness.

 

[DavisBJ]

Have you guys seen: A New Scientist article reports the finding of this massive ocean(s) in "the layer of hot rock between Earth's surface and its core." It's said to be three times the volume of all the earth's oceans.

This provides massive evidence for the validity of Dr. Walt Brown's Hydroplate Theory as well as ...

Do you actually understand science at all?

 

[Yorzhik]

OK, Let’s keep that idea on a back burner, and we’ll pick it up again if something lending support to it comes up.

So what is the field strength that is being measured in the bands? What have found is that it can be in the hundreds of nT in strength. Is that what you've heard?

Wiki says the earth's field is 25-65 mT at the surface. Any data on the mid Atlantic ridge? Or is it assumed to be roughly the same?

Not so. Think about this. If, as science contends, the oceanic crust is formed by slow seafloor spreading, with basaltic magma slowly filling in the gap and hardening into new seafloor, then in fact the seafloor is largely of the same rock that the upper regions of the mantle are. It’s just that in the case of the seafloor, the basaltic magma has been cooled enough to harden into basaltic rock. And, basaltic rock has very slightly higher density than basaltic magma. That means we have a heavy layer floating on a lighter liquid. That is an unstable situation. In the seafloor case, the oceanic plate is a wide and rather thick sheet riding on top of an immensely viscous fluid of only slightly less density. Once something forces an edge of that oceanic plate down into the mantle, there will be an actual gravitational pull helping the dense oceanic crust to sink further down.

This is just the thing. If gravity is pulling the underlying crust down, then it won't pick the overlying crust up. And with all that weight I doubt the tensile strength of crust bending into the mantle would do much of anything to pull crust under other crust.

The density differences are very subtle, heat conduction is very slow, and the viscosity is immense. Support for this idea comes from seeing that old oceanic crust (which has had more time to cool and is therefore more dense) is seen to subduct at a steeper angle than younger crust.

That's just not going to get crust to do all the crashing/lifting/folding we've seen it has done.

I don’t know what you mean when you say “seafloor away from the bands”. As to what the magnetic orientation of the deeper regions of the oceanic crust are, I haven’t seen any data on that. You have something specific?

I was taking one teachers word for it. He still hasn't gotten me the data and I doubt he will because he knows I'm YEC while he is a common descentist, and he's busy.

But, when I speak of the bands I'm talking about the bands near the oceanic ridge. They are the most cited when discussing reversals because they are the clearest. The bands away from the ridge get muddled and appear to point in the wrong direction sometimes. So the seafloor away from the bands is the seafloor away from the ridge and the field doesn't always point in the right directions there.

Secondly, within the bands themselves when data on their magnetic field much deeper inside is tested they frequently don't go in the right direction.

The bottom line, it seems to me from this scant evidence seems more in line with there being more to the story.

And I'm not relying on this kind of scant evidence to say reversals didn't happen. It is only to point out that the positive evidence for reversals is not as strong as it first appears.

Plate tectonics won a place as a credible scientific theory against a formidable amount of scientific skepticism. There sure are details that are being worked out, and questions still without answers, but there isn’t a field of science that the same can’t be said for. A (true) scientist doesn’t discard a theory at the first sign that it didn’t give ready answers to some questions. Frequently investigating the anomalies ultimately broadens and buttresses the theory.

No doubt. But the anomalies are pretty big and when added up they should at least allow for big competing theories. There is a lot we know about how the earth is working and it isn't fixing the anomolies.

Here you go taking something that I said I did not know (what magnetic pattern on the Pacific plate is) and decreeing that shows plate tectonics is wrong. For you to make that logical leap, you would have to have the information I said I did not have, about the magnetic characterization of the Pacific plate. Cough it up and tell me.

I didn't say that was a deciding factor. I said it was one question among many. We do have some data on the Pacific ocean, and it appears that everything is moving toward the ridge, not away from it.

What are the facts you are saying don’t support a reversing dipole? The relevant facts I am aware of are that there is a pattern of magnetic stripes on the seafloor and the seafloor is spreading slowly. Creationists (and scientists) say the earth’s magnetic field has been decreasing in strength. These facts look like something like a reversing dipole could help answer.

The big fact that works against the reversing pole is simple physics. There must be energy that moves the dipole so suddenly. That energy not only doesn't exist, but if it did a rather complicated machine would be needed to direct the energy.

 

[Nick M]

Oh Nicky, see I asked Yor for citations. That means I asked him for the evidence from scientific journals with respect to the claim he made about the magnetically alternating strips on either side of the mid-Atlantic ridge.

Said another way....

No

 

[DavisBJ]

But the anomalies are pretty big and when added up they should at least allow for big competing theories.

I am going to respond to this comment first. I read this as saying

But the anomalies are pretty big and when added up they (they = mainstream scientists) should at least allow for big competing theories.

​

“They” do. You know that no theory in science is immune from challenge by competing theories. But be careful, because that challenge needs to come from a true competing scientific theory, not from a theory in the way the word “theory” is understood in casual street talk.

FYI – I just flew into Japan, and I expect to be here well into the summer. My time is limited, and I don’t have access to my home library, so I will hold off on engaging points I would need my library for.

This is just the thing. If gravity is pulling the underlying crust down, then it won't pick the overlying crust up. And with all that weight I doubt the tensile strength of crust bending into the mantle would do much of anything to pull crust under other crust.

Your wording suggests you don’t understand what is meant by crust. If you are conversant with the following, let me know. Much of what I say about crust Walt Brown does not contest.

There are two types of crust. I was careful to specify “oceanic crust” as the type that subducts. But oceanic crust is pretty much what it says, under the ocean, only. Continents, however, sit on continental crust, a completely different kind of rock. Continental crust is typically about 2.7 grams/cc, whereas oceanic crust is 3.0 grams/cc (10% more dense than continental crust). Since the basaltic magma in the mantle deep beneath all crust is just a very little less dense than oceanic crust, I’ll call it 2.95 grams/cc.

The relatively light (2.7 gm/cc) continental crust just plain will not subduct into the denser (2.95 gm/cc) magma, anymore than a light log will dive beneath the water on a lake.

So, when a slab of continental crust finds itself banging into a slab of oceanic crust, it’s no contest. The continental crust is very “strongly” floating on the underlying magma, and the dense oceanic crust would have descended into the magma long ago had the viscosity been much less and the oceanic crust in small pieces. Result – oceanic crust subducts under continental, every time.

When a slab of oceanic crust bangs into another slab of oceanic crust, then it’s kinda like a quick negotiation on which slab stays up and which goes down. Each slab pulls out its birthday card, and shows the other how old it is. Slab “A” says, “I see you, slab B, are 40 million years old, and I am 150 million years old”. These slabs are miles and miles thick, and heat does not conduct through rock readily. So the older slab has had more time for its heat to diffuse into the ocean above, and thus it is slightly colder, and more importantly, denser. Result is slab A says, “I’m denser than you, and therefore gravity pulls me down more than you. I’m subducting.”

When a slab of continental crust bangs into another slab of continental crust, neither one is even a candidate for subduction. Then it is a pushing match of incredible forces. There is no “gravity … pick(ing) the overlying crust up”, as you say. But think of a D-10 caterpillar within its blade close to the ground as it goes across a rough field. Soon it will be pushing a wall of rocks and dirt whose top is spilling over the blade, much higher up than any of the rocks were originally. Gravity doesn’t have to push up for up mountains to form.

I know Walt talks about how implausible it is for the momentum of these colliding masses to push up mountains, but that is just Walt appealing to the ignorant by resorting to silly caricatures. Momentum is not involved.

If you had lived long ago on the northern edge of India when it was a separate land mass from Asia, migrating north, and was just touching the southern boundary of Asia, you would have observed a fairly tranquil scene. Over your lifetime the merge of the two land masses would probably have progressed a couple yards. But if you don’t think India forced its way into Asia, then why are there ongoing geological studies documenting continuing distortion of the Asian continent indicating India is not done with its northward migration?

 

[Daedalean's_Sun]

It does have that characteristic, but there are so many spots that don't follow the direction as it should (some even go in the wrong direction) that reversals are normally not followed far from the Mid Atlantic ridge.

What is "the wrong direction" when we are talking about magnetic reversals?

 

[Daedalean's_Sun]

Have you guys seen: A New Scientist article reports the finding of this massive ocean(s) in "the layer of hot rock between Earth's surface and its core." It's said to be three times the volume of all the earth's oceans.

:doh:

You realize they are not talking about flowing liquid water, right? We're talking about microscopic ions trapped in rock, that collectively account for a lot of water.

...Olivine is ringwoodite at this depth, a layer called the mantle transition zone. And it resolves a long-running debate about water in the mantle transition zone. The ringwoodite is 1.5 percent water, present not as a liquid but as hydroxide ions (oxygen and hydrogen molecules bound together).

http://www.scientificamerican.com/a...earths-mantle-holds-an-oceans-worth-of-water/

 

[Yorzhik]

I am going to respond to this comment first. I read this as saying

But the anomalies are pretty big and when added up they (they = mainstream scientists) should at least allow for big competing theories.

​

“They” do. You know that no theory in science is immune from challenge by competing theories. But be careful, because that challenge needs to come from a true competing scientific theory, not from a theory in the way the word “theory” is understood in casual street talk.

I know. The problem is a "true competing scientific theory" is nothing but a true Scotsman. There are competing theories (yes, I know what a 'theory' means in the ivory tower of academia sense) that answer some of the obvious problems that plate tectonics has. Yet instead of tacit interest which true scientists should have, the theories are ridiculed because the bearer of the theory is not politically correct. And I'm not just talking about Walt Brown. There are other theories opposed to both Plate Tectonics and Walt Brown that are also scorned without even looking at them because they are catastrophic theories instead of uniformitarian.

Your wording suggests you don’t understand what is meant by crust. If you are conversant with the following, let me know. Much of what I say about crust Walt Brown does not contest.

There are two types of crust. I was careful to specify “oceanic crust” as the type that subducts. But oceanic crust is pretty much what it says, under the ocean, only. Continents, however, sit on continental crust, a completely different kind of rock. Continental crust is typically about 2.7 grams/cc, whereas oceanic crust is 3.0 grams/cc (10% more dense than continental crust). Since the basaltic magma in the mantle deep beneath all crust is just a very little less dense than oceanic crust, I’ll call it 2.95 grams/cc.

The relatively light (2.7 gm/cc) continental crust just plain will not subduct into the denser (2.95 gm/cc) magma, anymore than a light log will dive beneath the water on a lake.

So, when a slab of continental crust finds itself banging into a slab of oceanic crust, it’s no contest. The continental crust is very “strongly” floating on the underlying magma, and the dense oceanic crust would have descended into the magma long ago had the viscosity been much less and the oceanic crust in small pieces. Result – oceanic crust subducts under continental, every time.

When a slab of oceanic crust bangs into another slab of oceanic crust, then it’s kinda like a quick negotiation on which slab stays up and which goes down. Each slab pulls out its birthday card, and shows the other how old it is. Slab “A” says, “I see you, slab B, are 40 million years old, and I am 150 million years old”. These slabs are miles and miles thick, and heat does not conduct through rock readily. So the older slab has had more time for its heat to diffuse into the ocean above, and thus it is slightly colder, and more importantly, denser. Result is slab A says, “I’m denser than you, and therefore gravity pulls me down more than you. I’m subducting.”

When a slab of continental crust bangs into another slab of continental crust, neither one is even a candidate for subduction. Then it is a pushing match of incredible forces. There is no “gravity … pick(ing) the overlying crust up”, as you say. But think of a D-10 caterpillar within its blade close to the ground as it goes across a rough field. Soon it will be pushing a wall of rocks and dirt whose top is spilling over the blade, much higher up than any of the rocks were originally. Gravity doesn’t have to push up for up mountains to form.

I know Walt talks about how implausible it is for the momentum of these colliding masses to push up mountains, but that is just Walt appealing to the ignorant by resorting to silly caricatures. Momentum is not involved.

If you had lived long ago on the northern edge of India when it was a separate land mass from Asia, migrating north, and was just touching the southern boundary of Asia, you would have observed a fairly tranquil scene. Over your lifetime the merge of the two land masses would probably have progressed a couple yards. But if you don’t think India forced its way into Asia, then why are there ongoing geological studies documenting continuing distortion of the Asian continent indicating India is not done with its northward migration?

Nothing you've said here do I disagree with. Nothing you've said here addresses the problems raised either.

Correct me if I'm wrong, but you've said in the past that not only is a subducting plate being pushed by the underlying mantle current, but that it is also being pulled by the falling leading edge. That falling leading edge is being pulled, supposedly, by gravity. And that plate is moving under and pushing up the crust it is subducting under. Therefore, gravity is contributing to lifting the plate that the pulled plate is going under. Here we can extend your analogy: Let's say that D-10 is unable to push the rocks with its own power so a cable is attached to it and the cable is thrown over a cliff with a great weight... and now the D-10 with the extra help can push the rocks up over the blade. Voila, gravity is lifting the rocks.

Does it appear we are on the same page so far?

 

[Yorzhik]

What is "the wrong direction" when we are talking about magnetic reversals?

Wrong direction = field direction not expected or predicted by the theory.

 

[JosephR]

real science as I understand it, are finding ways to extend human life beyond the earth , I think it is known we have seed plots and other things on the moon and in the international space station... thats what they tell us, so what do you think they dont tell us? and alot of theoretical physicist are saying that we are getting to a point, a point of either being successful and achieving life outside of our planet and solar system before we destroy ourselfs. I think they say we may have done this before, more then a few times, but that dont jive with YEC.

We are coming to a point of epic proportions on our part and human survival. This is usually where we meet God or the 2nd coming is really needed. I see three options, 1 we nuke or bio kill ourselfs and start over. 2 we succeed and human life continues even after our sun fails, 3 Jesus comes back before 1 and saves us.

Sorry to be so off topic but just some thoughts on this with religion and science both in mind.

 

[DavisBJ]

Nothing you've said here do I disagree with.

I am glad you concur in what I said, but I want to point out that plate tectonics, as I described it, necessarily involves millions of years. With that in mind, are you still in agreement?

Nothing you've said here addresses the problems raised either.

Correct me if I'm wrong, but you've said in the past that not only is a subducting plate being pushed by the underlying mantle current, but that it is also being pulled by the falling leading edge. That falling leading edge is being pulled, supposedly, by gravity. And that plate is moving under and pushing up the crust it is subducting under. Therefore, gravity is contributing to lifting the plate that the pulled plate is going under. Here we can extend your analogy: Let's say that D-10 is unable to push the rocks with its own power so a cable is attached to it and the cable is thrown over a cliff with a great weight... and now the D-10 with the extra help can push the rocks up over the blade. Voila, gravity is lifting the rocks.

Does it appear we are on the same page so far?

I understand your D-10 scenario, but I don’t see an analogy in plate tectonics. You refer to the subducting plate pushing the overlying plate up. Admittedly as the subducting plate descends there is scraping of the surface of the subducting plate against the edge of the overlying plate, but that results in forces in 2 directions on the overlying plate. First, the subducting plate pushes horizontally on the overlying plate, and in return the counter-force on the subducting plate helps bend it down so it is pointed at a descending angle into the mantle. This force & counter-force, although huge by man’s standards, is seldom enough to cause significant folding of strata such as is required for mountains to be forced up. The second direction the subducting plates exerts force on the overlying plate is down (not up). I will speak to this in an example below.

Just a side note for clarification. When subjected to great forces, rocks can respond rapidly in 3 ways. If they are cool (not near their melting temperature), and not under much confining pressure (pressure from all sides, such as happens deep in the earth), they usually just fracture – they are brittle. If they are cool but a bit deep, so the confining pressure is high, when subjected to a new directional force they can be distorted in shape within a limited range. If that new directional force is relieved they will spring back to their original shape. This property is called elastic deformation or elastic rebound. The third way rocks can respond to great force is when they are hot, but not molten, and usually under confining pressure. In this case the rocks actually flow, with the crystals shifting into new places that tend to minimize the pressure. When the new force is removed, the rocks retain their modified shape. This is called plastic deformation. (Plastic deformation can occur under less drastic conditions of heat, but then the process is vastly slower.)

Now let’s look at a recent real-life case – the 2011 Japan Tohoku earthquake. This is a case of oceanic crust subducting under another oceanic crust. As the huge Pacific plate creeps towards Japan, a hundred miles or so off the eastern Japanese coast it begins to curl down and dive under the plate the Japanese islands are on. A number of years ago (a century?) somehow the edge of the plate the Japanese islands are on essentially snagged on the surface of the descending Pacific plate. The descending Pacific plate started dragging the edge of the overlying plate down with it. The horizontal forces here were the descending plate trying to push the overlying plate, islands and all, towards China. That caused horizontal compression of the overlying plate (elastic deformation), and the counter-force of the overlying plate probably slowed the descent rate of the Pacific plate, resulting in elastic deformation in the descending plate as well. In the vertical direction the overlying plate was being warped, literally bent, downwards as the Pacific plate continued to subside. The Pacific plate’s descent rate might have slowed as a result.

When the stress finally got too high, back in 2011, and something finally sheared, the immense energy that had built up in each of the elastically deformed plates allowed them to snap back to where they would have been if the snag had never occurred. The northern part of Japan’s Honshu island (directly in line with and closest to the snag) quickly became a couple yards wider. Part of the descending plate may have descended at an angle for several yards at hyper-speed (for a tectonic plate). And the only substantial upwards motion in the whole scenario was when the down-twisted edge of the overlying plate elastically rebounded up, lifting a gazillion gallons of overlying ocean up as it did so (leading to a tsunami).

So, in summary, the descending plate did not lift or force up the overlying plate, no mountain building. Just shaking across Japan, devastation in northern Honshu, and hours of incredible video.

 

[Yorzhik]

I am glad you concur in what I said, but I want to point out that plate tectonics, as I described it, necessarily involves millions of years. With that in mind, are you still in agreement?

You're right, I was sloppy, I should have left off the last two paragraphs, or at least said "I agree with the science part of what you said."

It's true that when two plates run into each other, one will most likely be heavier than the other. So if they keep pushing against each other, the heavier one will go under the lighter one.

But that's as far as it goes. Because there are problems with the idea that one will slide under the other and lift the other up.

I understand your D-10 scenario, but I don’t see an analogy in plate tectonics.

The idea came from you, if I recall correctly. You said there was a combination of the gravity pull from the leading edge of the subducting plate along with the push of the currents in the mantle that could push a plate (without momentum) under another plate.

I think this idea is wrong on a few levels.

You refer to the subducting plate pushing the overlying plate up. Admittedly as the subducting plate descends there is scraping of the surface of the subducting plate against the edge of the overlying plate, but that results in forces in 2 directions on the overlying plate. First, the subducting plate pushes horizontally on the overlying plate, and in return the counter-force on the subducting plate helps bend it down so it is pointed at a descending angle into the mantle. This force & counter-force, although huge by man’s standards, is seldom enough to cause significant folding of strata such as is required for mountains to be forced up.

OK, I've been referring to the plate that goes underneath another plate as a subducting plate, but that doesn't see to be accurate. So let's call them the plates-that-go-under-other-plates. Seems kind of clunky, but one should be accurate.

So, these plates-that-go-under-other-plates could either subduct or they could just keep sliding under, as India appears to be doing to the Tibet.

There are problems with both scenarios. Either the plate that goes under will stop because the pushing power of the mantle isn't enough if the friction of the overlying plate keeps increasing.

In the case of the plate subducting, for example at the Andes, where the sediments should be the greatest, which would be the leading edge of of overlying plate, we don't find them. And secondly, something you mention next, the plate should be pulling the Andes down, not pushing them up. And of course, despite being a little lower in density, such a subtle density difference cannot overcome the not-so-subtle weight of the Andes.

The second direction the subducting plates exerts force on the overlying plate is down (not up). I will speak to this in an example below.

Just a side note for clarification. When subjected to great forces, rocks can respond rapidly in 3 ways. If they are cool (not near their melting temperature), and not under much confining pressure (pressure from all sides, such as happens deep in the earth), they usually just fracture – they are brittle. If they are cool but a bit deep, so the confining pressure is high, when subjected to a new directional force they can be distorted in shape within a limited range. If that new directional force is relieved they will spring back to their original shape. This property is called elastic deformation or elastic rebound. The third way rocks can respond to great force is when they are hot, but not molten, and usually under confining pressure. In this case the rocks actually flow, with the crystals shifting into new places that tend to minimize the pressure. When the new force is removed, the rocks retain their modified shape. This is called plastic deformation. (Plastic deformation can occur under less drastic conditions of heat, but then the process is vastly slower.)

Now let’s look at a recent real-life case – the 2011 Japan Tohoku earthquake. This is a case of oceanic crust subducting under another oceanic crust. As the huge Pacific plate creeps towards Japan, a hundred miles or so off the eastern Japanese coast it begins to curl down and dive under the plate the Japanese islands are on. A number of years ago (a century?) somehow the edge of the plate the Japanese islands are on essentially snagged on the surface on the descending Pacific plate. The descending Pacific plate started dragging the edge of the overlying plate down with it. The horizontal forces here were the descending plate trying to push the overlying plate, islands and all, towards China. That caused horizontal compression of the overlying plate (elastic deformation), and the counter-force of the overlying plate probably slowed the descent rate of the Pacific plate, resulting in elastic deformation in the descending plate as well. In the vertical direction the overlying plate was being warped, literally bent, downwards as the Pacific plate continued to subside. The Pacific plate’s descent rate might have slowed as a result.

When the stress finally got too high, back in 2011, and something finally sheared, the immense energy that had built up in each of the elastically deformed plates allowed them to snap back to where they would have been if the snag had never occurred. The northern part of Japan’s Honshu island (directly in line with and closest to the snag) quickly became a couple yards wider. Part of the descending plate may have descended at an angle for several yards at hyper-speed (for a tectonic plate). And the only substantial upwards motion in the whole scenario was when the down-twisted edge of the overlying plate elastically rebounded up, lifting a gazillion gallons of overlying ocean up as it did so (leading to a tsunami).

So, in summary, the descending plate did not lift or force up the overlying plate, no mountain building. Just shaking across Japan, devastation in northern Honshu, and hours of incredible video.

In fact, it appears that the Japan coast when down when the 2011 earthquake happened. That's not what was expected.

 

[DavisBJ]

I should have … at least said "I agree with the science part of what you said."

That is little different than what you said before. It isn’t just part science. What part do you not agree with that makes the millions of years go away so you can agree with the rest?

It's true that when two plates run into each other, one will most likely be heavier than the other. So if they keep pushing against each other, the heavier one will go under the lighter one.

No, no, no. Every time I have spoken of one plate subducting under another, it has been an oceanic plate that subducts, specifically because only oceanic plates can penetrate the upper mantle and have gravity aiding the subduction process. But if we are dealing with two slabs of continental crust - let me repeat what I posted a couple posts back:

When a slab of continental crust bangs into another slab of continental crust, neither one is even a candidate for subduction. Then it is a pushing match of incredible forces.

Except in very unusual cases, continental crust does not subduct, period. Even if one of the continental slabs is of somewhat lower density than the other, still each is too light for subduction to occur.

As to a heavier continental slab going under a lighter one (but not subducting into the mantle), in a limited sense that could happen. There are well-known processes in geology (called overthrusts and underthrusts) where massive layers of rock can be forced to slide over or under already in-place strata. But those are not unique to colliding plates.

But that's as far as it goes. Because there are problems with the idea that one will slide under the other and lift the other up.

Rather than vague allusions to “problems with the idea”, how about enumerating the issues? “It just can’t happen” is a pretty wimpy argument to make, especially when that very process is being studied and documented as it occurs.

(On the D-10 idea) The idea came from you, if I recall correctly.

It was your use of the D-10 idea, involving what effectively is a cable over a pulley so that gravity assists in the pulling that I see no equivalent of in plate tectonics.

You said there was a combination of the gravity pull from the leading edge of the subducting plate along with the push of the currents in the mantle that could push a plate (without momentum) under another plate.

I don’t think, at least in this thread, that I have said anything about the mantle drag on a plate forcing it along.

I think this idea is wrong on a few levels.

I appreciate the sentiment, but san specifics, this is no more than a doubt in your mind.

OK, I've been referring to the plate that goes underneath another plate as a subducting plate, but that doesn't see to be accurate. So let's call them the plates-that-go-under-other-plates. Seems kind of clunky, but one should be accurate.

Subducting plates are ones that, once started, continue to sink because they are more dense than the medium they are sinking into.

So, these plates-that-go-under-other-plates could either subduct or they could just keep sliding under, as India appears to be doing to the Tibet.

(I have found that Knight is pretty tolerant of long posts, if they are on-subject and pertinent. I hope this qualifies.)

Let me supply some important details that have not been covered about continental crust – continental crust collisions. There are similarities between the continental crust “floating” on the mantle, and icebergs floating in the ocean. When you see the towering wall of iceberg that your ship is about to hit, you know that, impressive as the ice you see is, under the part you see, below the ocean surface, is a vastly bigger mountain of ice actually holding the ice you see above the waterline. This is due to simple laws of hydrodynamics – the ice is only slightly less dense than the water. The difference between the weight of the ice actually below the surface and the weight of the sea water that would have been where the subsurface ice is has to equal the weight of the above water ice. The laws of hydrodynamics still apply.

Similarly continental crust is slightly less dense than the mantle material. And, just like the iceberg, when you climb 10,000 feet high on a mountain, the crust extends 50,000 or 100,000 feet or more below you. Mount Everest is a very minor hill compared to the depths the crust extends below it.

Now think of India pushing into Asia. If some of India is being forced between layers in Asia, causing the upper part to lift, keep in mind that in reality is occurring in the very upper layers of the continental crust.

There are problems with both scenarios. Either the plate that goes under will stop because the pushing power of the mantle isn't enough if the friction of the overlying plate keeps increasing.

Yup, but hasn’t reached that point yet in Tibet.

In the case of the plate subducting, for example at the Andes, where the sediments should be the greatest, which would be the leading edge of the overlying plate, we don't find them.

I am not aware of this, so pending specific data, I will withhold comment.

And secondly, something you mention next, the plate should be pulling the Andes down, not pushing them up. And of course, despite being a little lower in density, such a subtle density difference cannot overcome the not-so-subtle weight of the Andes.

I didn’t say anything about the Nazca Plate or the Andes. But your belief that the Andes should be being pulled down indicates another fundamental misunderstanding of plate tectonics. You do realize that the Andes are part of the “ring of fire”, a nearly continuous string of volcanoes encircling the Pacific Ocean. And that there is an almost perfect correlation between that ring of fire and a nearby ring of deep-ocean trenches caused by subduction zones? That is one place where two apparently dissimilar geological structures – ocean trenches and volcanoes – consistently occur in such close proximity that there almost has to be a causal relationship. And there is.

Side note. I recall seeing several graphics in prior recent TOL threads that I think cover this. I will verbally cover it again, but not a third time. I don’t mind explaining, unless I realize I am covering ground with the same person that they pretended to understand before (which happened with a TOL regular a year or so ago).

Briefly – the Nazca plate subducts under the west coast of South America. As it descends at an angle, the increasing temperature of the mantle around it starts heating it up slowly, and the confining pressure goes up in the plate. When high enough pressures and temperatures are reached, some of the minerals within the descending plate are forced to undergo chemical changes, with one result being that some (a lot of) hydrogen and oxygen atoms are set free. They combine into free water molecules. These water molecules are much lighter than the near-magma they were just set free from, so they begin to rise vertically, as much as the still high viscosity permits. This occurs under areas well inland of the coast, since that is where the angled descent of the subducting plate has carried it.

It is known that the addition of water to high-temperature basaltic magma – mantle rock – lowers its melting temperature. So the part of the mantle just above the descending plate gets an influx of superhot water, and it essentially melts. Its viscosity is now much lower than typical mantle at that depth, and so it starts rising, by sort of melting its way upward. When it finally reaches the bottom of the continental crust, it can melt that too, and it may incorporate some silicates (continental type rock) into the rising mass of magma. If there is sufficient heat, the rising blob may make it all the way to the surface, erupting as a member of the ring of fire. If not enuff heat, then the rising blob may cool off and harden far underground.

So, the Andes are volcanoes, created and fed by subduction processes.

In fact, it appears that the Japan coast when down when the 2011 earthquake happened. That's not what was expected.

So? Lots of specifics about that earthquake were a surprise. You want to see if you can go down 20 miles below the ocean surface and come back with a detailed map of the faults, surface characteristics of the subducting plate, and so on? You find one earthquake that is outside the norm, and that means the hundreds of previous advances in earthquake understanding are bogus? I hope you are not that desperate.

 

[DavisBJ]

Regarding correct use of the term evolution or evolutionist

Regarding correct use of the term evolution or evolutionist

Hello DBJ,
…
I'm familiar with Spike's work, and I don't recall him using "Theory of Evolution" to refer to astrophysics, and I'm sure that I never have. So being 0-for-2 there, you'd have to show me where Hovind used it that way before I'd credit you for being correct regarding him.

But I do contend you, like many creationists, have such a pathological dislike of Darwinian evolution that you substitute the word “evolutionist’ as a pejorative against scientists whose work is completely apart from the Darwinian meaning of the word. Case in point, years ago on your program you were discussing the moon dust question with a caller, and you said,

… when NASA designed the Lunar Landers, they designed them with feet – very wide pods – because the evolutionists feared that the moon would have dozens of feet of dust, or hundreds of feet of dust. And they engineered for that. And when they got there they said, well they found there’s only a couple inches of dust. And creationists took that argument and said, in fact they predicted, look there will only be a couple inches of dust on the moon because the moon is not millions of years old, it’s relatively young. It’s only thousands of years old. And so what the evolutionists did, when they got to the moon they didn’t find 50 or 100 feet of dust. They said, “You know what, we miscalculated the amount of dust in the solar system…” (BEL095, 2006)

​

According to the words from your own mouth, NASA designed the pads on the Lunar Lander legs because “EVOLUTIONISTS” had fears about the depth of the dust. And it was “EVOLUTIONISTS” that you say admitted to miscalculating the depth of the moon dust. Are you going to stoop to pretending that your use of the word “evolutionist” in the above was simply because some parts of NASA’s design evolved?

I use theory of chemical evolution for that, and theory of solar system evolution for that, or for short, chemical evolution, planetary evolution, stellar evolution, etc.

Sorry, but your own words falsify your testimony.

Why are you guys so touchy when it comes to the evolution label? You remind me of abortionists who don't want to be called abortionists, and liberals who get upset when we call them liberals.

You remind me of someone who so hates aspects of science that might conflict with your theology so you resort to calling NASA aerospace engineers “evolutionists”.

 

[Stripe]

:mock: evolutionists.

Evolutionists love to complain about being called evolutionists rather than addressing something of relevance.

 

[Lighthouse]

:mock: evolutionists.

Evolutionists love to complain about being called evolutionists rather than addressing something of relevance.

Yup.

 

[Yorzhik]

It was your use of the D-10 idea, involving what effectively is a cable over a pulley so that gravity assists in the pulling that I see no equivalent of in plate tectonics.

I don’t think, at least in this thread, that I have said anything about the mantle drag on a plate forcing it along.

It was a different thread, but I haven't found the post. But I remember you saying the crust moved with a combination of gravity pulling one end and mantle currents pushing underneath.

Let me supply some important details that have not been covered about continental crust – continental crust collisions. There are similarities between the continental crust “floating” on the mantle, and icebergs floating in the ocean. When you see the towering wall of iceberg that your ship is about to hit, you know that, impressive as the ice you see is, under the part you see, below the ocean surface, is a vastly bigger mountain of ice actually holding the ice you see above the waterline. This is due to simple laws of hydrodynamics – the ice is only slightly less dense than the water. The difference between the weight of the ice actually below the surface and the weight of the sea water that would have been where the subsurface ice is has to equal the weight of the above water ice. The laws of hydrodynamics still apply.

Similarly continental crust is slightly less dense than the mantle material. And, just like the iceberg, when you climb 10,000 feet high on a mountain, the crust extends 50,000 or 100,000 feet or more below you. Mount Everest is a very minor hill compared to the depths the crust extends below it.

So then imagine, with almost no momentum, two abutting icebergs and one going under the other. It doesn't happen.

Now think of India pushing into Asia. If some of India is being forced between layers in Asia, causing the upper part to lift, keep in mind that in reality is occurring in the very upper layers of the continental crust.

Imagine an iceberg knifing into another iceberg with almost no momentum. Not only could it not happen, but the ice would sink to almost the same level as it had been.

Yup, but hasn’t reached that point yet in Tibet.

I just don't see where you are getting the energy from to knife continental crust into other continental crust. Where is India getting pushed from?

I didn’t say anything about the Nazca Plate or the Andes. But your belief that the Andes should be being pulled down indicates another fundamental misunderstanding of plate tectonics. You do realize that the Andes are part of the “ring of fire”, a nearly continuous string of volcanoes encircling the Pacific Ocean. And that there is an almost perfect correlation between that ring of fire and a nearby ring of deep-ocean trenches caused by subduction zones? That is one place where two apparently dissimilar geological structures – ocean trenches and volcanoes – consistently occur in such close proximity that there almost has to be a causal relationship. And there is.

OK.

Side note. I recall seeing several graphics in prior recent TOL threads that I think cover this. I will verbally cover it again, but not a third time. I don’t mind explaining, unless I realize I am covering ground with the same person that they pretended to understand before (which happened with a TOL regular a year or so ago).

I doubt it was addressed to me. I've never spent much time on this subject.

Briefly – the Nazca plate subducts under the west coast of South America. As it descends at an angle, the increasing temperature of the mantle around it starts heating it up slowly, and the confining pressure goes up in the plate. When high enough pressures and temperatures are reached, some of the minerals within the descending plate are forced to undergo chemical changes, with one result being that some (a lot of) hydrogen and oxygen atoms are set free. They combine into free water molecules. These water molecules are much lighter than the near-magma they were just set free from, so they begin to rise vertically, as much as the still high viscosity permits. This occurs under areas well inland of the coast, since that is where the angled descent of the subducting plate has carried it.

It is known that the addition of water to high-temperature basaltic magma – mantle rock – lowers its melting temperature. So the part of the mantle just above the descending plate gets an influx of superhot water, and it essentially melts. Its viscosity is now much lower than typical mantle at that depth, and so it starts rising, by sort of melting its way upward. When it finally reaches the bottom of the continental crust, it can melt that too, and it may incorporate some silicates (continental type rock) into the rising mass of magma. If there is sufficient heat, the rising blob may make it all the way to the surface, erupting as a member of the ring of fire. If not enuff heat, then the rising blob may cool off and harden far underground.

So, the Andes are volcanoes, created and fed by subduction processes.

OK.

So? Lots of specifics about that earthquake were a surprise. You want to see if you can go down 20 miles below the ocean surface and come back with a detailed map of the faults, surface characteristics of the subducting plate, and so on? You find one earthquake that is outside the norm, and that means the hundreds of previous advances in earthquake understanding are bogus? I hope you are not that desperate.

Are we so sure this is an anomaly? I don't think we've measured with the kind of accuracy we did this time. Maybe we did. But it would be something to check on before we say this is outside the norm.

 

[DavisBJ]

It was a different thread, but I haven't found the post. But I remember you saying the crust moved with a combination of gravity pulling one end and mantle currents pushing underneath.

I suspect mantle currents dragging on the crust are important, but that is not a view held uniformly by geologists. These are processes occurring far deeper in the earth than any man-made instrument has gone, and taking many many human lifetimes to move appreciable distances. That means the models we have are dealing with pressures and circulation rates vastly outside our usual experience. A small missed factor can drastically alter the results.

But the fundamental ideas are not much in dispute – the temperature and density properties of the interior of the earth. Whatever the correct description is for what is happening, it will involve fine tuning, not wholesale abandonment of the basics.

So then imagine, with almost no momentum, two abutting icebergs and one going under the other. It doesn't happen.

The only relevance that the icebergs have is to illustrate that what we see sticking up is only a small fraction of what is actually there, just like with continental crust.

Imagine an iceberg knifing into another iceberg with almost no momentum. Not only could it not happen, but the ice would sink to almost the same level as it had been.

I don’t know what the relevance of the “no momentum” qualifier is, unless you are pandering to the ignorant by making the idea of one land mass penetrating another look silly. I already faulted Walt Brown earlier for stooping to that level of discourse. So before I decide, can you supply sources showing that geologists believe that the momentum is a significant player in, say, the northern migration of India into the Asian continent?

I agree that if icebergs did end up getting squished together, they would essentially “sink to the same level as (they) had been.” Are you implying that is not the case in Asia?

I just don't see where you are getting the energy from to knife continental crust into other continental crust. Where is India getting pushed from?

Fascinating way you word the question. A real scientist would have said something like: “I just don't see where the energy is coming from to force continental crust to knife into other continental crust.” The way you word it makes it sound like a deficiency of the part of the plate tectonic community if they (we, I) don’t have an answer.

No matter, my answer is, I don’t know. I have some suspicions, but sans actually modelling and using such data as we do have, my guess is no more than a guess. For right now I will entertain the type of response the Christian Isaac Newton was wont to offer when he knew he had no adequate physical explanation for something observed – angels. Each morning for warmups, the angels line up and invisibly push India another fraction of an inch into Asia. Heck, maybe it’s the Christian angels proving they are tougher than the Buddhist angels.

OK.

Real informative response. Kinda like the Japanese word “Hai”, which can mean anything from “Yeah, I hear ya” to “You bet, I understand and will get right on it.”

I doubt it was addressed to me. I've never spent much time on this subject.

No, you are not the guilty party.

OK.

Do you agree, disagree, or is “Duh” the most you will commit to?

Are we so sure this is an anomaly? I don't think we've measured with the kind of accuracy we did this time. Maybe we did. But it would be something to check on before we say this is outside the norm.

Let’s see, this caused the largest earthquake ever known to have hit Japan, and this was the 5th largest earthquake in the world in the last century. And you think this one might be in the norm?

But now to backtrack to something you have avoided responding to. Back in post 90, in response to my explaining which type of crust subducts, and why, you responded with:

Nothing you've said here do I disagree with.

Based on your very concise and unambiguous statement, it certainly sounded like you, like tens of thousands of others, recognized a rational scientific explanation for some important aspects of plate tectonics. But when, in my response, I pointed out that immense spans of time were required, suddenly you realized that would violate an ultra-literal reading of the creation account that was recorded by nomadic tribes thousands of years ago, tribes whose scientific knowledge was below that of many modern elementary school children today. So given the choice between science and ancient tribal dogma, you recanted your assertion that the science was acceptable, and sided with goat herders as your gurus. You didn’t even pretend that your change was due to science, but due to an ancient religious account. I asked you what about the scientific account was wrong, that would justify your changing your mind. Silence has been your answer.