continental drift

"He's being generous to the ye-creationist crowd. If they drifted apart during the 40 days of tumult it would be more like 3 miles/hour."
--Hm.. I don't know where you got a limit of 40 days for this process, also, the atlantic plates shift from the middle outward, so you would divide by two.------------------

"JM: Isn't that how long the tumult of the flood lasted according to the Bible? After 40 days, the flood waters persisted,"
--This is how long rain fell, not the span of time for tectonic shifting."but there is no indication of a tumult. "
--What would you expect to find differently with a tumulted Flooding of the world?"You are assuming of course that the Atlantic is the only place that rifted and that the Euopean-North American boundary represents the greatest amount of separation."
--Oh of course not, you were addressing the atlantic plates. So I was making sure we know that they spread from the spreading center at the mid-atlantic ridge, thus it is an outward process (and you would divide by two). The pacific plate is the largest oceanic plate, though it's rate of subduction and its spreading regions are literally 10 times faster than the atlantic."If that is your assumption, then the 1/2 spreading rate would be 1.5 mph. If you look at a global picture, the rate of 3 mph is something you must contend with."
--it wouldn't be 1.5mph because the time span for this 'rush' isn't a mere 40 days, though this would have been when it was the most active."Either way, this rate is some 10^8-10^9 faster than we observe today. There are some serious physical problems with such rates"
--I would probably say it would be 500-2000 times faster than we observe today at some point in time.------------------

"someone demonstrate that this kind of drift is possible, and the mechanism driving it."
--Magma upwelling (I'm sure you've studied geology and the pangea breakaway) and heavy oceanic crust pushing against continental plates resulting in rapid subduction.------------------

"So, where are the subduction zones bounding the Atlantic Ocean where the oceanic plates are pushing the continents along?"
--In the Atlantic, If my mind serves me right, there is only one subduction zone and that is above cuba, which is one of the deepest in the world, the pacific plate (the ring of fire) is quite known for its subduction zones encompassing its perimeter. Magma upwelling is what forced the continents to split to form the mid-atlantic ridge and the atlantic ocean."Do you really think that you can push lithospheric plates from the spreading zones?"
--Why not? It happens all the time (otherwize the phenomena of plate tectonics would not exist).------------------

"You seem quite confident of that, but are you sure that the magma upwelling in the mid-ocean ridges is not an effect of the plates drifting apart, rather than the cause?"
--I am slightly confident, though I wouldnt come to a conclusion on this without either specific further reading, or discussion. I see no other cause of a 'pulling' effect to start this system off. I am aware that mantle convection would slightly drive a 'pulling' of the lithospheric plates away from the spreading centers. The means of the magma upwelling currently isn't the cause I know of plate divergence, I believe, it may be subduction. Though if my mind serves me correctly, what started this system off is an upwelling mantle by heat weakening the lithospheric plate and eventually rifting pangea. I am quite tired, I may be confused on a segment of this issue. ------------------

"JM: Well, let me help you out. The driving forces of the plates don't act alone. They work in harmony. As near as we can tell, the breakup of Pangea started with a huge mantle upwelling and that started the continents breaking apart. There are flood basalt provinces that make up sort of an ancient 'ring of fire' along the present-day Atlantic margins. This is probably the initial cause of Atlantic opening."
--This is what I have read, and it sounds feasible enough for me."Here's the problem as I see it. Creationists want to pick and choose the geology that they are willing to believe. For example, if you are going to accept this hypothesis for the initial splitting of the Atlantic, then you must accept the evidence for the synchroneity of the volcanism. In order to do that, you must accept the radiometric ages that attest to the synchroneity and/or the sequence of fossils that help provide a time line for the spreading. So, do you accept this geological conclusion?"
--I agree partly, at first, you asserted that we must accept the sequential deposition of volcanic deposits, I can agree with that. But then you take a down-drop and say that in order to do such a thing, you must accept radiometric dating to 'help provide a time line for the spreading'. This is a problem because you asserted that I must agree with the time-scale on deposition if I am to agree on the order and synchrony of this order. To illustrate this:This is my time-scale:
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1--2--3--4--5--6--7And this is your time-scale:
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1-----2-----3-----4-----5-----6-----7--You see, I can agree with the order at which events arose or a sertain form of sediment deposit was deposited, just as you can. Though I need not to agree on the time scale that you input into when these events took place. A shorter usually takes somthing such as your time and compresses it by intensifying or itterating it catastrophicly or something of that nature. I need not to accept this on radiometric dating, the mechenism of burrial may explain why we see relatively smaller quantities of radio nuclei, though I would have to research radiometric dating to come to the conclusion.------------------

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[This message has been edited by TrueCreation, 03-16-2002]

"In case you didn't notice, the Cuban trench does not exactly bound the entire Atlantic Ocean. Your earlier statement said that the oceanic crust pushing against the continents would result in rapid subduction as I remember. My point is that this is not always the case. So how does your model work for the Atlantic Ocean?"
--Yes I did notice that, that is why I gave location, and then I went to show the subduction properties of the pacific oceanic plate. I think there was a bit of missunderstandment there. The model for the atlantic would be as I said earlier:

quote:

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what started this system off is an upwelling mantle by heat weakening the lithospheric plate and eventually rifting pangea.

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--So this upwelling would result in the continents diverging at the spreading centers, as a process continued to have divergence take place, magma creates new oceanic basalt by preasure replacing the gap with basaltic ocean floor. Mantle Convection is what forces this action to continue in the atlantic rifts. If memmory serves, subduction should be taking place in the atlantic, though subduction zones are not present, possibly because of the slow spreading rate."It does? Just because you say so? Don't you think there are other mechanisms? I can think of three others without spraining a neuron. A lack of knowledge helps you overlook numerous facts in the geology of the earth and allow you to reconcile an ad hoc, flimsy concept of plate tectonics."
--I think I missinterpereted what it was that you were getting at when you asserted that 'you can push lithospheric plates from the spreading zones', I thought of it as if you did not think that the plates are not diverging.------------------