Tectonics of the Yellowstone hotspot wake in southwestern Montana: comment and reply

Traditional stratigraphic nomenclature shows that conglomerate with distinctive red quartzite roundstones flowed southward from southwestern Montana and that basalt spread northward from the Snake River Plain to backfill the Sixmile Creek which is considered to be paleovalley. However, informal sequence stratigraphy reveals that the sub-Sixmile Creek erosion surface is a regional or interregional characteristic and not a paleovalley.