Here's why:
* Divergent Plate Boundaries: These are areas where tectonic plates move apart, allowing magma to rise from the mantle and create new crust. This leads to features like mid-ocean ridges and rift valleys.
* Hotspots: These are areas of volcanic activity caused by plumes of unusually hot mantle material rising to the surface. The location of hotspots is relatively fixed, while tectonic plates move over them.
Yellowstone is situated on the North American Plate, but the hot spot beneath it is stationary. As the plate moves over the hotspot, it creates a trail of volcanic activity, which is evident in the chain of extinct volcanoes stretching from Yellowstone to the Snake River Plain in Idaho.
Therefore, Yellowstone's volcanic activity is not directly related to the movement of tectonic plates at a divergent boundary, but rather to the presence of a stationary hotspot.
