Skip to comments.The Case Against Pangea
Posted on 04/22/2012 3:53:17 PM PDT by Windflier
First its important to understand that this is the most profound disagreement in all of science in a century and a half and, even so, it is the tip of the iceberg, the ramifications of this disagreement will change everything we know in science, top to bottom.
To begin with basic stuff.
All science knows
The earth has two crusts. One the mostly basalt lower crust or the oceanic crust which is 2 4 miles deeper down than the higher upper continental crust. This lower crust, essentially covers the Earth. It this crust is being made daily at rift cracks that snake around the earths mid- oceans. But how could all these rifts continually spread apart without the Earth growing? Ah .that is the question .isnt it?
Sitting on or in and as part of the oceanic crust is the second higher upper crust or the Continental Crust rising for the most part out of the water. It is made mostly of granitic rock, which is 2.5 times the weight of water.
Some edge area of the Continental Crust or Plate dips into and under the sea level of the ocean. This area is what we call the Continental Shelf. So as you go out into the ocean and the water gets gradually deeper that is the Continental Shelf. At a given distance out into the ocean the ocean floor suddenly drops off and goes down like a plummet 2 ½ to 4 miles to the deep ocean floor, where we find the second lower crust, the Oceanic Crust made mostly of basalts which are 3.0 3.3 times the weight of water. So to make it visually clear, if you took the water away what you would see as you go out into the ocean a distance is, the Continental Shelf would suddenly drop away and down like a ridge in Arizona., except it would go straight down for two to three miles, as if it was suddenly broken off. The other side of that broken off ridge is across the ocean thousands of miles in Europe, or Africa and west to Australia and Asia.
How did the two sides of this higher crust spread apart?
Rifts or eruptive cracks in the ocean floor provide new material in the form of molten magmic rock that rises up at a rift area and the oceanic plate spreads apart and the two sides move away from each other smoothly and regularly, and so the continents welded within the oceanic plates also move apart as the ocean bottom spreads . Now if this happens and it does, all over the world, logically speaking, this Earth must grow.
We I argue that, that this outer crust originally covered the whole of a smaller Earth and the Earth sphere grew. The outer crust, therefore, had to crack and spread to accommodate a growing Earth which it apparently did.
We further argue that if you were to shrink the sphere of Earth
by letting the oceanic plate re-enter the rifts they erupted from, over time
the continental crust would easily and completely fit back together, and this solution satisfies all questions of tectonics, science, geology, paleontology, theoretical and practical physics, cosmology, and subatomic physics. Pretty simple actually.
BZZT! Wrong again.
A non-geologist, Wegner, first postulated the theory of continental drift, and was largely derided because he could propose no logical mechanism for such to work.
It wasn't until we started remotely exploring the seafloor and discovered spreading centers and subduction zones that the mechanism became clear - that the continents moved on plates that include both oceanic and continental crust. It was a gradual process of acceptance of the theory due to accumulating evidence, not of making the evidence fit the theory. That is extremly well-documented.
A prime example is the formation of the Himalaya. The top of Mount Everest is oceanic sedimentary rock. That is rock that was from the ocean that used to be between the Indian continent and the Eurasian continent. Continental drift closed that ocean and the two continental masses collided, which is why the Himilaya are so high. Your guy's theory provides no viable mechanism to explain that.
And slivers of oceanic sediment caught between the two are present all over the Himalaya, as they are in mountain belts around the world - such as the ultra-mafic rocks such as serpentine, formed in oceanic crust, that form belts in the Piedmont, the core of an ancient mountain range. That was not determined by animations and amatuer theorists, it was determined by geologists going out into the field and getting actual rock samples - actual geology as opposed to the armchari type.
There are also pillow lavas formed at spreading centers found on land around the world as well.
So you show a lack of history of the theory of plate tectonics, of the rocks of mountain ranges and basic structural geology. Which is apparently why you are a sucker for this particular internet shyster.
Both theories have the landmasses fitting together at some point. So if the puzzle pieces are good for one they’re good for both, and if you have to question them breaking up in one you have to question it for both.
I’m not vehemently opposed to his theory, I’m vehemently opposed to his LIES about other theories.
Pangea explained ping
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