In O Atlas da Terra-médiaKaren Wynn Fonstad usa seu conhecimento de cartografia para estimar muitos detalhes da geografia da Terra-média. Para fazer isso, ela usa os mapas desenhados por Tolkien, além de dicas do texto dos livros. Aqui estão algumas de suas conclusões relacionadas às cadeias de montanhas.
Montanhas Enevoadas
As Montanhas Nebulosas estão a milhas 900 de norte a sul e têm cerca de 10 metros de altura.
THE TOWERING MOUNTAINS OF MIST were undoubtedly one of the most important features in Middle-earth. It is quite likely that they, as well as the White Mountains, were inspired by the European Alps, in which Tolkien had hiked in 1911. The Hithaeglir, raised by Melkor early in the First Age as a hindrance to the riding of Oromë, were a barrier to early westward migrations and to the quests of both Bilbo and Frodo. The north-south orientation of some 900 miles would also have blocked the predominating moist winds from the west. The orographic lifting, possibly to as high as 12,000 feet, would have produced the cloudy conditions that not only gave the range its name, but that were more locally important in naming Fanuidhol (Cloudyhead), and especially in producing the tremendous thunder-battle from which Thorin and Company sought shelter.
The Atlas of Middle-earth Karen Wynn Fonstad: The Misty Mountains
Houghton Mifflin Harcourt. Kindle Edition.
In O Hobbit, os anões viajam cerca de 30 quilômetros da "varanda da frente" dos duendes no oeste até a porta dos fundos no leste. Enquanto eles estavam viajando na direção noroeste, a largura da cordilheira devia ter sido de aproximadamente 20 milhas neste momento.
The Atlas of Middle-earth Karen Wynn Fonstad: The Misty Mountains
Houghton Mifflin Harcourt. Kindle Edition.
As Montanhas Brancas
As Montanhas Brancas estão a milhas 600 de oeste a leste e têm mais de 10 metros de altura.
THE SECOND MAJOR RANGE of mountains spanned some 600 miles, west to east. The White Mountains were present in the First Age1 and were quite likely raised at the same time as the Towers of Mist. Their northern arm even appeared to be an extension of that north-south range, merely eroded away at the Gap of Rohan.
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Many other portions of the White Mountains must also have been as high as most of the Misty Mountains, or higher, in order to remain snowcapped at the more southerly latitude.
The Atlas of Middle-earth Karen Wynn Fonstad: The White Mountains
Houghton Mifflin Harcourt. Kindle Edition.
Ephel Dúath
Os Ephel Dúath formam a parede oeste de Mordor. Karen Wynn Fonstad estima que o passe de Cirith Ungol está mais do que o 3,000 acima da encruzilhada. com os picos circundantes sendo mais altos, mas não tão altos quanto as Montanhas Enevoadas ou Montanhas Brancas (porque não são cobertas de neve). Ela descreve o Ephel Dúath como visto por Frodo e Sam da passagem de Cirith Ungol.
Around them the peaks rose high above, but were apparently lower than those of the White and Misty Mountains. No mention was made of snow, although “forgotten winters had gnawed and carved the sunless stone.” Still, the peaks were probably quite high, for the top of the pass of Cirith Ungol was more than 3000 feet above the Cross-roads.
The Atlas of Middle-earth Karen Wynn Fonstad: Mordor (and Adjacent Lands)
Houghton Mifflin Harcourt. Kindle Edition.
Juntando tudo isso, estimo que a passagem de Cirith Ungol não exceda os pés 4,000 acima do nível do mar (pressupõe que as estradas transversais estejam a menos de 1,000 pés acima do nível do mar) e os picos do Ephel Dúath estão entre 6,000 e 9,000 pés altos (mais altos que Cirith Ungul, mas baixos o suficiente para não ficarem cobertos de neve). Pelos mapas de Tolkien, calculo que o Ephel Dúath se estendesse 400-500 quilômetros de norte a sul.
Udûn e Mount Doom
Udûn é o vale circular atrás do portão Negro. Karen Wynn Fonstad ressalta que ele poderia ter sido criado pela explosão de um enorme vulcão, mas esse vulcão teria que ter o 29,000 pés de altura. Ela também calcula que o Mount Doom está a uma distância de 5 km de largura e a 3 metros de altura.
At the north end of the Ephel Dúath, at its junction with the Ered Lithui, lay a deep circular valley ringed by sheer black barren cliffs—Udûn. Tolkien described the vale as being encircled by arms sent out by the two ranges. The symmetry of the valley suggests either a caldera or a ring-dike. A caldera is the remnant of a volcano that has exploded and/or collapsed. A ring-dike is a circular ridge of cooled igneous rock surrounding a deep valley. It occurs when a round block subsides into an underlying magma chamber and the fluid magma is forced up around the edges. Often the upwelling is intermittent, leaving passes such as the Isenmouthe and Cirith Gorgor. Either process could have resulted in the feature shown by Tolkien, although compared with our world either would have been gigantic. Imagine the original height of a volcano with a forty-five-mile base. This colossus would have towered almost 29,000 feet! In contrast Mt. Doom was only seven miles across and stood 4500 feet.
The Atlas of Middle-earth Karen Wynn Fonstad: Mordor (and Adjacent Lands)
Houghton Mifflin Harcourt. Kindle Edition.