Some argue that the formations were overturned, but again the extent of overturn involved seems to raise extreme problems. In the Empire Mountains in southern Arizona, Permian limestone rests on top of Cretaceous. The contact resembles gear meshing. There could have been no sliding without the projections of the lower formation being ground off. Yet it is called an overthrust.
Fossils are in the wrong order in Heart Mountain, Wyoming, and in nearby Sheep Mountain.
These mountains are capped with Paleozoic limestone. Lower down are Jurassic and Tertiary sediments. An impossible combination of fossils was reported found in 1970 in Guryul Ravine, Kashmir. Permian brachiopods were found mixed with lower Triassic pelecypods. In the past decade, studies of plant spores have been made in the formations of the Grand Canyon.