The flora/fauna world and how Weirwood.net works was described well with this post by If you have not read the post: The Grand Weirwood Conspiracy: We need to talk about Pando. I suggest you do. For everything ASOIAF for each ying there is a yang. Ice & Fire
The Ring of Fire is a major area in the basin of the Pacific Ocean where a large number of earthquakes and volcanic eruptions occur...it is associated with a nearly continuous series of oceanic trenches, volcanic arcs, and volcanic belts and/or plate movements. The Ring of Fire is sometimes called the circum-Pacific belt.
King's Landing was specifically selected as the capitol city for a specific reason - it has three volcano cones.
Red Keep is on Aegon's High Hill.
http://awoiaf.westeros.org/images/1/1e/Visenyas_Hill.jpg
The Others are attempting to corner the market on obsidian
Hardhome is an old volcano, a place where obsidian is made> Why Hardhome? The Others' Campaign
The firewyms are in lava tubes
Outside of Asshai, there is an active volcano, the smoke of which is causing the shadows.
Mother of Mountains and the Womb of the World.
