GEOLOGY

Detailed explanation-1: -Over 16.5 million years, the hot spot has generated 15 to 20 massive eruptions that left large volcanic depressions called calderas. The McDermitt Volcanic Field, located on the Nevada-Oregon border, is the hot spot’s oldest large feature. It formed from an eruption roughly 16.1 million years ago.

Detailed explanation-2: -With continued activity, the previously formed volcanic islands on the plate move away from the hot spot, making room for new islands to be formed by subsequent volcanic activity. Volcanoes become inactive, their edifices are eroded, and they gradually sink below sea level.

Detailed explanation-3: -Summary. Volcanoes grow above hotspots. A hotspot is a zone of melting above a mantle plume. Hotspot volcanoes are better able to penetrate oceanic crust than continental crust.

Detailed explanation-4: -Progressively older volcanoes form linear chains on the surface of the moving tectonic plate, downstream of the hotspot. Earth scientists use the directions of these volcanic chains, along with the age progression of the chain’s volcanoes, to reconstruct histories of the relative motion between plates.