A Creation Ministries International article makes the following claim about the multiple-local-flood explanation for the deposits at the Morrison Formation:
The idea of many local floods might at first seem a possibility. However, a notable feature of the water-worked sandstone in which the dinosaur bones are entombed complicates the picture for uniformitarians—these rocks contain abundant grains of a rock called ‘tuff’. Tuff forms from the solidification of hot ash ejected from volcanoes. This, and layers of volcanic ash elsewhere in the formation indicate that an explosive volcanic eruption occurred at much the same time as all the dinosaur remains were buried by flooding. No volcano is known in the vicinity of the deposit, and geologists have placed the nearest source for the tuff to vents in southern California or Nevada. Ash clouds depositing over such considerable distances point to an extremely catastrophic volcanic event.
The coincidence of floods and eruptions happening together on multiple occasions, over vast spans of time, stretches the credibility of the uniformitarian ‘just so’ story.
Has tuff been found amongst the deposits at the Dinosaur National Monument? Is this incongruous with the scientific consensus that the fossils were produced at various times hundreds of millions of years ago, rather than all at once in a worldwide flood event?