Hmmm...are the moutains between Skyrim and Morrowind high enough to be comparable to the Himalayas? And is there volcanic activity associated with the Indian subcontinent's collision with Asia, anyway?
There is, but not as much as say a Subduction zone. It's two bits of Continental crust colliding, just like Africa and the Eurasian plate. These sorts of Collisions cause uplift, Mountain building.
Volcanoes generally form when a plate descends underneath a another plate, or there is a divergent plate boundary. The first case is a subduction zone. All one has to do is outline the Pacific Ring of Fire, then look at the Plate boundaries the majority of Volcanoes form on, which is predominantly subduction zones.
The Second case is a Rift valley. Where two plates separate. The Mid-Atlantic Ridge, and the East Pacific Ridge are examples of this, as well as the East African Rift Valley.
The Bonestrewn crest volcano could be on a subduction zone, but the evidence does not support that conclusion as of yet. It's far to large of a caldera to be that. It could also be a Rift Valley, but at the same time, Rift Valleys follow the plate boundry. We don't see that at Bonestrewn Crest. It's a single crater in the earth, most certainly not a valley.
That only makes sense if each region is a continent. Which, given they form a single land mass, and can each be walked across in a few days... probably not.
Besides, a fair bit of the volcanic activity (at least in Morrowind) has nothing to do with conventional sources of lava, which would tend to mess up any efforts at plate techtonics.
Someone does not know how Faulting works. Look no further then the Great Basin in the American West. In this region, you have mountains followed by Valleys followed by Mountains, followed by Valleys. It goes on like that for hundreds of miles. This is caused by many numerous faults in the area. http://explanet.info/images/Ch08/08_12a.jpg. This was caused by the North American continent splitting apart along the area of the Mississippi river. This is also the location of one of most dangerous faults in North America, the New Madrid fault. Back in the Cretaceous, this area was actually an inland sea that linked the Hudson bay to the Gulf of Mexico. The faulting here actually split the continent for a while.
There can be faults, but no Plate boundary to explain them.
Very Well could be, that is, after all, what Yellowstone is, a Hot spot smack dab in the middle of the US.