Hello everyone,I just watched a video lecture by Nick Zentner where he presented an alternative event from Basil Tikoff and others.The alternative event is opposed to the widely accepted flat slab subduction of the Farallon plate under North America.To paraphrase, this is a fairly new idea where instead of flat slab subduction, NA had a westward collision with an exotic terrane.
What do you guys think?
EDIT: Found a related paper
Although plate tectonics didn't become mainstream science until after Lord of the Rings was published, a map of the Misty mountains eastward presents an interesting and geologically feasible history of that area of the continent, as well as an explanation of some of the layout of Moria.
The names of both mountain ranges provide a distinction between the two. The suffix "-aeglir" is a series of peaks, whereas the word "Ered" is a series of mostly separate mountains. These two different names point to a difference in structure, implying a difference in the processes that formed each.
The Ered Mithrin appear to decrease in size (judging from a map of middle-earth) as they approach the misty mountains, after which, they end and do not extend further westward. The Ered Mithrin end at the Misty mountains as the continental boundary destroys any geologic record by subduction. Even the name and appearance of the Ered Mithrin as a series of mountains indicate that they are a series of extinct hotspot volcanoes, similar in nature to the Hawaiian islands on Earth.
The misty mountains themselves, however, are described as not a chain of mountains (ERED Mithrin), but as a series of connected peaks (hithAEGLIR) with especially tall peaks interspersed throughout. This appears to be a typical continent-continent convergence zone, complete with crumple zones on either side of the mountains.
The presence of tunnels deep at the roots of the Misty mountains are further evidence of an active ancient subduction zone. As the Misty mountains were raised by Melkor, some crust would have been forced under other crust, generating convergent-boundary volcanism. As these volcanoes went extinct as the mountains finished forming, the magma chambers and tubes left behind would have drained. It's entirely feasible that somehow, a magma tube to the top of an extinct volcano could have been connected to a magma chamber at the base of the mountains, forming the basis for the stair from the "lowest dungeon to the highest peak".
Such are the ramblings of a bored geologist.
Hi all, I was looking at a map of pangea from 260mya and 240mya courtesy of Mr. Scotese, and It looks like the collision of Baltica and Siberia created the Ural mountains around this time and right next door the siberian traps unloaded a flood basalt eruption that would kick start the great dying. Is there a connection between the mountain building and the opening of the siberian traps? almost everything I've heard and read doesn't make any connection between the two
Hi. I am interested in learning more about mountain building. I have a BS in geology so I know some basics, but I'd like to read some more detailed papers. As it is a rather broad topic, I'd enjoy influential papers on specific aspects that shed much needed light on the subject when they were published, but more general papers are good, too. I want to build a mountain of knowledge on this topic. Please make suggestions, thanks.
I have been taught that plate tectonics is the formation mechanism of mountains. However, some parts of McPhee's "Annals of the Former World" gave me the impression that some geologists think that some mountains are born not through plates pushing and thrusting against each other but are born through a different (or additional?) process. Is there currently any divide in the academic world on mountain formation? What are some alternate theories of mountain formation?
orogeny
noun: The process of mountain building by the upward folding of the Earth's crust.
Word of the day Provided by : wordnik
https://en.m.wikipedia.org/wiki/Wissahickon_Formation
The Wissahickon Formation is a metamorphic formation in Pennsylvania, New Jersey, and Delaware.
The three main orogenies that built the Appalachian Mountains (oldest to most recent) are the Taconic, Acadian, and Alleghenian.
Since the Acadian and Alleghenian occurred afterword, how is it possible that they did not further deform this formation?
In the Wikipedia article, look under Age, and then under Deformation age.
FYI this is not a homework question -- I graduated.
https://preview.redd.it/2v8ylkzhpbb31.jpg?width=4608&format=pjpg&auto=webp&s=2f675f1c506698dba1a1f83f73a2f625524b8f70
