If you like to see the extent to which fans will engage with a source material:
Middle-Earth gets a Geological Makeover | Green tea and Velociraptors
Middle-Earth gets a Geological Makeover | Green tea and Velociraptors
Istari
Mythic Scribe
Apprentice
Istari
Dark LordI think that Tolkien did not really care about realistic geology, and from my point of view, this tells us that we should not always take so seriously the realistic details and construction of our Fantasy worlds.
In my opinion, there can indeed be such a thing as too much worldbuilding.
Scribal Lord
MystagogueNo matter how boring a book is, leave cats out of it! They've done nothing wrong...usually.
Dark LordI mean, why is Mordor a high plateau surrounded by mountains, like it was a natural fortress or something??
IstariYou saying mountains don't have rivers? Huh?I dunno. There has to be a midpoint between overexplaining and rivers that run through mountain ranges (thank you, Paolini!)
One of the Maiar to be more precise. IIRC, the term "Ainur", though not technically wrong, is generally used to describe their state of being outside of Eä.Perhaps Sauron took a few thousand years to shift the landscape around so that Mordor would essentially be a fortress. He was an Ainur, after all.