Nelson and Grand (2018) used core waves to show a low velocity plume from the core/mantle boundary to the surface in the vicinity of Yellowstone. Their plume is steeply inclined, travelling half as far horizontally as vertically. Their paper provides a section below and depth slices showing plume locations used further below in relation to the Shatsky path.

Nelson and Grand’s Section Annotated with radii and cords used to project beyond their depth slices

Nelson and Grand’s Section line on a map of USArray seismic stations

The notion of Shatsky subduction goes back at least to Saleeby (2003), Liu et al (2008, 2010) extended the concept. Humphries et al (2015) produced the base image below adjusting Liu’s (2010) track to better match tomography.

Image from Humphries (2010) annotated with depth slices and projections from the section. The track of Humphries would be adjusted somewhat further NW by widely agreed corrections to Farallon plate motion by Torsvik et al 2019 now incorporated in GPLATES

What could this correlation possibly mean? Can a plume beginning at 2900 km depth be meaningfully related to the passage a 30 km deep ocean plateau? Did Shatsky drag upper mantle and the plume head with it? Did the plume draft in Shatsky’s wake?

Is this just pure coincidence?