I used to work with a guy who during his misspent youth was part of a group trying to set a record for the tallest cave systems, so they were looking high in the mountains and for certain geological formations.<p>The insight he shared with me was that caves don’t form in the softest or most permeable layers of rock. Instead they tend to form above the hardest layers - water wants to seek the lowest level and the only thing to stop it is a layer that’s hard, or impermeable. Whatever is above that is where the water does most of its work, even if there are softer layers further up.<p>So if I have it right, these dinosaur footprints were made upon a softer layer above very hard material that makes up the base of the cave, and the layer above those two was hard enough that it has so far resisted erosion, leaving effectively a stone cast of a dinosaur foot, rather than a footprint that has somehow been flipped 180 degrees.
Here's a link to an article from April 2nd that actually shows a picture of the cave ceiling: <a href="https://www.nature.com/articles/d41586-020-00972-y" rel="nofollow">https://www.nature.com/articles/d41586-020-00972-y</a>
Party hard<p>Apart of that, the presence of the footprints in the upper strata is not particularly strange. Dinosaur footprints are not so easy to spot for a non specialist. Often just a round concavity in the floor that could be done by anything.
This is a really neat discovery. For those in the western US there is a pretty accessible sauropod trackway in Grand Staircase National Monument at a place called Twenty Mile Wash that is well worth checking out.