Explanations for Pangea

Nah. Don't want your autobiography. And sure as hell wouldn't pay for it.

Like I said, it's just nice to see that you've settled on something closer to the truth this time. Makes me all warm and stuff inside.

And. Yeah. It does contradict pretty strongly with what you've said before. But, that's what we expect from you.

Carry on.

 

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I have four degrees if that helps you any feel more warm and stuff inside but you're still not saying what I said different from the past, though my life is so complex and full that I do lose track sometimes: to human is to error. What do your posts have anything to do with this thread? Starting on being obnoxious again as usual, rather than congenial?

I wish I could find more solid dating on the formation - or rather, the deformation - of the Appalachian mountains after the breakup of Pangea and the Grenville belt intrusive suites after around one billion years ago and what happened to the Appalachians after that as part of the buildup from pre-existeing eastern Laurentia (the proto-North American craton).

 

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Self indulgent, pretentious little prick. Nice to see such consistency,

 

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The problem with the Grenville Orogeny is that there is no conclusive decision on the dates relating to the Adirondacks or of the island arcs that formed the Southern and Western portions of the North American Craton.

For example, the Clare shear zone must pre-date the Grenville Orogeny, but how can this be? There is no suffficient data for this yet. The Clare shear zone is late-or post-Grenville and a boundary to the Adirondacks.

The Allegheny Front and Appalachian Orogeny:

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Wikipedia states that:

"By about 300 million years ago (Pennsylvanian Period) Africa was approaching North American craton. The collisional belt spread into the Ozark-Ouachita region and through the Marathon Mountains area of Texas. Continent vs. continent collision raised the Appalachian-Ouachita chain to lofty, Himalayan-scale ranges. The massive bulk of Pangea was completed near the end of the Paleozoic Era (Permian Period ) when Africa (Gondwana) plowed into the continental agglomeration, with the Appalachian-Ouachita mountains near the core.

Pangea began to break up about 220 million years ago, in the Early Mesozoic Era (Late Triassic Period). As Pangea rifted apart a new passive tectonic margin was born and the forces that created the Appalachian, Ouachita, and Marathon Mountains were stilled. Weathering and erosion prevailed, and the mountains began to wear away.

By the end of the Mesozoic Era, the Appalachian Mountains had been eroded to an almost flat plain. It was not until the region was uplifted during the Cenozoic Era that the distinctive topography of the present formed. Uplift rejuvenated the streams, which rapidly responded by cutting downward into the ancient bedrock. Some streams flowed along weak layers that define the folds and faults created many millions of years earlier. Other streams downcut so rapidly that they cut right across the resistant folded rocks of the mountain core, carving canyons across rock layers and geologic structures."

Most of this is very factual, but some partially conjectural and I think it should be rewritten - but only if there are more researched facts conducive to more accuracy.

 

Appalacian Orogeny:

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This is basically what I am referring to. You can see the Grenville Orogeny at the bottom (basement complex), but few articles talk about it since then - since Pangae and Laurentia. Yet, you can see that there were many other orogenies involved, for the Catskills, Adirondacks, Trans-Hudson. These orogenies are not very well documented in detail in the journal literature.