Talk:Geology of the Appalachians

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This article seems to be about the geology of the Appalachians, rather than a general geography of the Eastern US. I propose moving this to Geology of the Appalachians. -- hike395 13:55, 2 Jun 2005 (UTC)

Something missing here

This is a long wordy outdated 1911 description. Not one mention of plate tectonics or even a link to Appalachian orogeny! The short section on geology in the Appalachian Mountains is more informative. A massive rewrite is needed, the mountains haven't changed much since 1911, but the understanding of geology sure has. -Vsmith 01:46, 27 Jun 2005 (UTC)

Which 1911 article is this from? I can't find it. Thanks! -- hike395 05:03, 27 Jun 2005 (UTC)

Don't know which one. The style seemed to fit and see this [1] edit from Feb. 2003. -Vsmith 28 June 2005 03:46 (UTC)

OK. As a substitute, how about Talk:Geology of the Appalachians/restart? I wikified a USGS web page, so it should be up-to-date. I'm not enough of an expert to go into more detail, especially on the regional geology. Should we move this restart page to the main page? -- hike395 28 June 2005 05:01 (UTC)

If 1911 geology is bad, should we just delete the rest of the article (below the introduction)? -- hike395 04:12, 15 November 2005 (UTC)

I dont see how any one could defend keeping the 1911 material, not unless its been vetted by an expert and brought up to modern standards. Based on the comments by Vsmith above, its not been done. --Stbalbach 04:54, 15 November 2005 (UTC)

Appalachian Basin

Appalachian Basin redirects to this article. That term is usually associated with coal, oil and gas in shale discussions. There's no mention in the article about minerals and gas in this article.Americasroof (talk) 15:57, 19 May 2010 (UTC)

This part is just glossed over:

By the end of the Mesozoic Era, the Appalachian Mountains had been eroded to an almost flat plain.[4] It was not until the region was uplifted during the Cenozoic Era that the distinctive topography of the present formed.[5] 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.

What caused this uplift? It seems like a pretty important thing to discuss since it's entirely responsible for the mountains we know today. — Preceding unsigned comment added by 73.200.17.87 (talk) 18:19, 23 July 2023 (UTC)

The cause of the uplift isn't known definitively, although there have been a number of explanations put forward. Here's a recent review of the latest evidence and theories: https://www.sciencedirect.com/science/article/abs/pii/S0169555X22003427

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It might make sense to add this information to the article, but I'll leave that to someone with more than a layman's understanding. Markthomasvia (talk) 02:16, 9 November 2023 (UTC)

Rewrite initiated

This article misses about 500 million years of Appalachian Mountain geology. I have placed edits within the [[Appalachian Mountains]] article and am proposing the same here.

File:Rodinia reconstruction.jpg

Proposed reconstruction of Rodinia for 750 Million years ago (0.75 Ga), with orogenic belts of 1.1 billion years ago (1.1 Ga) highlighted in green. While the rift edge is shown lower than, and parallel to, the equator at the time of the Rodinian formation and drift, subsequently, there was a counter-clockwise drift of Laurentia and the early Blue Ridge.

The first mountain-building tectonic plate collision that initiated the construction of what are today the Appalachians occurred about 1 billion years ago when the pre-North American craton called Laurentia collided with three other cratons, Kahlahari, Rio Plato, and Amazonia. All the other cratons of the earth also collided at about this time to form the supercontinent Rodinia and were surrounded by one single ocean. Mountain-building referred to as the Grenville Orogeny occurred along the boundaries of the cratons as illustrated in the nap of Rodinia at the right. These became the Blue Ridge Mountains, as illustrated in the subsequent figure that shows the USGS physiographic provinces of the Appalachians in the United States.

A look at rocks that are exposed in today's Appalachian mountains reveals elongated belts of folded and thrust faulted marine sedimentary rocks, volcanic rocks and slivers of ancient ocean floor, which provides strong evidence that these rocks were deformed during plate collision.

USGS Appalachian zones in the United States

Subsequent construction of the Appalachians occurred some some 480 million years ago, culminating in the construction of the supercontinent Pangaea with the Appalachians near the center. Because North America and Africa were connected, the Appalachians formed part of the same mountain chain as the Little Atlas in Morocco. This mountain range, known as the Central Pangean Mountains, extended into Scotland, before the Mesozoic Era opening of the Iapetus Ocean, from the North America/Europe collision (See Caledonian orogeny). Deanrah (talk) 21:14, 16 August 2023 (UTC)

References