WHAT’S BEING CLAIMED:
- An ancient stone slab was excavated and first put on display in 1896 — 123 years ago.
- The 11-foot-long slab of sandstone was marked with different prints: dinosaur tracks, several grooves, and pairs of depressions.
- The grooves and depressions on the stone slab have only recently been identified.
An 11-foot-long slab of sandstone that had dinosaur tracks, among other markings, was excavated from a quarry in Portland, Connecticut over a century ago. Though it was first on display at Wesleyan University in 1896, the other prints and grooves on it have only recently been identified.
The dinosaur footprints belonged to Anchisaurus, a prosauropod dinosaur that emerged during the late Jurassic period.
The series of grooves alongside the dino tracks, according to Lamont-Doherty Earth Observatory paleontologist Paul Olsen, point to so-called sailing stones. These are rocks that mysteriously propel themselves across desert landscapes, and one may have “sailed” across this slab once before.
In 2014, the mystery of how these rocks moved was solved when scientists found that thin sheets of ice that formed on the rocks enabled winds to propel them, leaving behind grooved tracks. Olsen says that it’s also possible that microbial mats made the rock slick enough to sail over the slab 100 million years ago.
The region where the slab was excavated was humid and tropical about 200 million years ago. Olsen explained at the annual meeting of the American Geophysical Union (AGU) held on Dec. 9 that if the stone was coated with ice, it could be strong evidence that the area could have gone through an ancient cooling period.
Lastly, pairs of small depressions were identified aside from the dinosaur and sailing stone tracks. Olsen says that these prints point to a small, unidentified mammal that hopped across the slab’s surface. That mammal was most likely making its way to its burrow.
Source: Live Science