This conclusion comes from evolutionary Dinosaur researchers!!
“Dinosaur National Monument in Vernal, Utah, USA, is world famous for its display of a water-laid jumble of disarticulated dinosaur bones.151 … Colbert described the stacked dinosaur bones in Howe Quarry, Wyoming, USA as being “… piled in like logs in a jam”.153 Robert Bakker can’t help but think of a cataclysm when viewing the dinosaur graveyard at Como Bluff, Wyoming: “Anyone who cherishes notions that evolution is always slow and continuous will be shaken out of his beliefs by Breakfast Bench [Como Bluff] and the other geological markers of cataclysm.”
“This was no ordinary spring flood from one of the streams in the area, but a catastrophic inundation”
John Horner and James Gorman, Digging Dinosaurs, 1988, p. 131.