Submarine canyon formation theories

[CharlieO]

BOERSEUN: Admittedly I have problems with a very slow dial-up and poor connection, which makes searching for claims you made about my posts very time consuming. Re: "You say you can't imagine Pangaea tearing itself to pieces."

Couldn't find that statement you attributed to me anywhere. Perhaps you could locate it for me if you did for yourself?

While not the issue of this thread, what I did write was, "Clearly, to me at least, ALL the continents were once much larger in size and were also connected together, everywhere, on a not too much smaller Earth. This made more sense to me than a Pangaea located as a lump of crust on only one side of Earth."

Still seems logical to me and, I must add, to many others who dare to wonder and speculate as to possible alternatives. I even provided a possible mechanism for Earth's expansion in an earlier post: Hydrogen molecules emerging from a dense, highly compacted, metallic hydrogen core, changing phase and effusing into Earth's mantle, thereby expanding between other crystals and increasing overall size as hydrogen embrittlement still does today in industry, while still retaining the same total mass and density. This is a process which I have personally initiated under laboratory conditions and one possible explanation for those who are not so devoted to one dogma that they can consider other alternatives.

Not exactly sure what you meant by, "But I can guarantee you that with all the diverse causes of canyon-forming, an alternating expanding/contracting Earth has never, and will never feature. And only because it doesn't happen." Sounds pretty absolute to me and I guess you are saying an alternating expanding/contracting Earth has never and will never happen. Is that correct? If so, I wish I could be so certain about dogmatic beliefs. But then, not too long ago, most scientists were claiming Earth was flat, while others also claimed the Sun rotated around Earth. In 1928, Will Rogers wrote: "So much of what we KNOW, ain't true." Amen.

While again not the issue, I must explain my creed as an explanation for my efforts, "I cannot conceive of anyone surviving their physical death, yet I can respect and sympathize with others believing they might be rewarded in their afterlife. I only want to know more about life's present mysteries and will strive to comprehend a portion, be it ever so tiny, of the Reason manifesting itself in Nature. When I die, that others found my efforts worthwhile is the only reward I seek."

As for the issue of this thread, you seem to be saying undersea canyons are formed in several ways: "Crustal movement, subduction, erosion, volcanic activity, rifting, all play a part" - - with no mention of subaerial erosion by river flows across once dry lands.

Have you ever considered the grandeur of these submarine canyons, some of which are deeper, longer and wider, with a larger displacement than the Grand Canyon by many factors? Did you also fail to consider the fact that oceans have coastal currents, most of which flow at right angles to exiting subaerial river flows and their submarine canyons? Ocean currents can only distribute river sediments along their coasts and river deltas, they can't erode submarine canyons. Hardly any support for Turbidity currents and their debris, which many still claim to have eroded most submarine canyons. Also please consider, many submarine canyons have rising water currents, called upwelling, which carry deep sea nutrients to their coasts and supports local fishing industries.

One feature of submarine canyons you might also consider is the existence of Plunge Pools beneath escarpments located across these submarine river courses. Plunge Pools are eroded depressions resulting from water falling freely from above. These are also evident on land, such as those currently found beneath Niagara Falls, Yellowstone Falls and ALL others; albeit many submarine canyon plunge pools are larger overall and thus evidence of much greater water flows falling freely from escarpments high above; which would be illogical, if not impossible for underwater currents. Can you tell me how an upwelling submarine canyon current could dig out a plunge pool while flowing straight up a now submerged escarpment?

You might also consider the sand from continental sources, now deposited in obvious layers along submarine river banks, just as they are found today along subaerial rivers, with clearly evident wind blown ripples and sand dunes on their surfaces, now stabilized underwater. Then consider the cobbles or rounded river rocks, again of continental sources, which can be found in these former river beds, now hundreds of miles from shorelines. I doubt if any of this could develop underwater thru crustal movement, subduction, volcanic activity or rifting, or even Turbidity currents.

The latter appears to be both difficult to locate and, when some underwater currents were found, they appeared to be too weak to create such dramatic effects or even leave evidence of their passing.

Now I am aware that some claim the ocean floors must have risen tens of thousands of feet above existing sea levels by Tectonic means, so the evident subaerial erosion could occur, while sea levels remained within a limited range of several hundreds of feet. If so, then all the sea floors rose at the same time and this would require a suddenly expanded Earth and then a slowly condensing Earth, so there goes your absolute "never, and will never" contention. So I think we can agree to ignore this claim as being illogical.

So what is it about an expanding Earth or a dried out Earth, or both, that creates such resistance to even the consideration of possible alternatives? Could it be your education has robbed you of any imagination or the ability to deviate from current dogma? Noting that dogma often changes slowly over time. Flat Earth, remember? In any event, I can sympathize with those both lacking imagination and unable to even consider possible alternatives, just as I can sympathize with like-minded Creationists.

However, if you can clearly disprove the underwater evidence of subaerial erosion by rivers flowing across once dry continental shelves and margins, onto ocean floors, please inform the many researchers who have devoted their professional lives to this study: Shepard, Gross, Landes to name a few. You might also want to contact the Editors of the Encyclopedia Britannica, the Coast and Geodetic Survey, the Geological Society of America, Scripps Institution and many other marine research organizations all over the world, which have concluded these sea-floor canyons have all the characteristics of river canyons and are distinctly different from fault valleys.

Shepard writes: "Also tests of the idea that the submarine canyons might be the product of currents have produced negative results so that they have evidently been cut by rivers. The significance of this sub-aerial erosion on the present sea-floor is particularly disturbing, since the submarine canyons extend out to depths of from 2,000 to as much as 10,000 feet and are found off practically every coast of the world."

I'm sure he would appreciate learning the error of his conclusions, if you were able to disprove the physical facts he observed over his 50 years of marine research.

Meanwhile, I can agree, as CraigD hopefully offered, the subaerial erosion of now submarine canons is a simplistic explanation, but the physical evidence seems clear. I believe it was Einstein who said the simplest explanations are usually the most correct. E=MC^2.

Regards, CharlieO