Question

### Models of Yellowstone Volcanism

Yellowstone National Park is characterized by intense geothermal activity and a history of supervolcanic eruptions. The Yellowstone volcanic system has produced a southwest-to-northeast track of progressively younger volcanic calderas over the past $16.5$ million years. Geologists debate the primary mechanism driving this volcanism.

Model 1 (Plume Hypothesis)
Yellowstone volcanism is driven by a deep mantle plume—a narrow column of hot, buoyant rock rising from the core-mantle boundary (approximately $2{}900\text{ km}$ deep). This plume remains relatively stationary relative to the deep mantle. As the North American plate moves southwestward over this stationary plume at a rate of $2.3\text{ cm/year}$, decompression melting at the plume head generates magma that periodically erupts, leaving a path of calderas. The primary source of heat is primordial thermal energy from the Earth's core.

Model 2 (Lithospheric Extension Hypothesis)
Yellowstone volcanism is driven by shallow, upper-mantle processes and plate tectonics, not a deep plume. As the North American plate stretches and undergoes lithospheric extension due to tectonic forces, pre-existing crustal fault zones and shear lines fracture. This fracturing allows pre-existing, ambient magma in the upper mantle (at depths less than $200\text{ km}$) to escape to the surface. The age progression of the calderas is due to the sequential reactivations of these fault systems as stress propagates through the plate, rather than a stationary heat source. The primary source of heat is local radioactive decay and shear heating within the upper mantle.

Match each scientific claim or description below to the model(s) that support or include it.