However I concluded that a shallow impact would not create the same wave patterns, since it was a lateral impact, not perpendicular. If there was indeed a structure similar to the one you mention, I believe it would lie somewhere in North America (possibly even South America), somewhere along the 70th meridian West. You want to jump on my bandwagon? Start looking for it, I would start in Northern Quebec and work South.
If you ponder this a bit more absinth, I feel you will free your mind a little more, and that my hypothesis will make more sense to you. I can be stubborn at times too but take a line from the new film avatar
'I cannot teach someone whos cup is already full...'
Which is exactly why I believe I am fighting am uphill battle, not with just you, but the scientific community by enlarge.