Velocity structures outlining the Yellowstone’s upper-crustal magma reservoir based on sparse (left) and dense (right) seismic networks

Comparison between the velocity structures outlining the Yellowstone’s upper-crustal magma reservoir at 5 km (3 mi) depth based on sparse (left) and dense (right) seismic networks. The open squares denote the locations of seismic sensors. Warmer color indicates lower velocity, representing higher melt fraction within the medium. The denser seismic array clearly has much better resolution of the seismic velocity structure. Adapted from Wu et al. (2023).