25 June 2011
A major discovery
Posted by Callan Bentley
Visiting Butch Dooley and crew on a dinosaur dig in the Jurassic Morrison Formation on Wednesday morning, I did a lot of wandering around the area, dubbed the Two Sisters site. I noticed something in the sandstone at the top of one hillock, and thought it looked like a sauropod footprint:
(The depression is filled in with modern mud.)
I took a photo, and thought, I need to ask Butch if there have been any trackways reported from this site. I recalled seeing sauropod tracks in the Morrison at its type locality, in Morrison, Colorado, at Dinosaur Ridge. But there were other distractions at Two Sisters, so I strolled on, and then I noticed something else:
That’s three similar looking concave-up disks of sandstone, differentially weathering out from the silty matrix and sliding downhill. If these really are sauropod tracks, then perhaps the compression of the sand and mud under the dinosaur’s weight rendered the footprints more compact and resistant to erosion, so they stand up relatively tough and coherent, while the rest of the rock falls apart and erodes away…
Closeup portraits of all three:
The one at the top of the hill from the top…
…and from the side…
Butch blogged it up here, and though he’s not 100% sure, he seems to think I’m on to something! That would be pretty cool, from the point of view of my ego. Though I’m no paleontologist, I’m thrilled to potentially discover something previously unknown, and potentially significant.
Callan Bentley is Associate Professor of Geology at Piedmont Virginia Community College in Charlottesville, Virginia. He is a Fellow of the Geological Society of America. For his work on this blog, the National Association of Geoscience Teachers recognized him with the James Shea Award. He has also won the Outstanding Faculty Award from the State Council on Higher Education in Virginia, and the Biggs Award for Excellence in Geoscience Teaching from the Geoscience Education Division of the Geological Society of America. In previous years, Callan served as a contributing editor at EARTH magazine, President of the Geological Society of Washington and President the Geo2YC division of NAGT.
Good luck; keeping my footprints crossed!
that is awesome. good eye!
That is the most fantastic find! Please keep the blog updated. Do they know what type of dinosaur they were excavating?
They look remarkably like the Sauropod prints I find on the coastal exposures here in Scarborough (UK)
When I’ve got a few minutes spare I’ll mail you a few pictures.
You might like to contact the Dinosaur Footprint Group at Sheffield University, Martin White and Mike Romano would be able to help as they are amongst the top people in the field.
Seconded.
The featutres appear to be very similar to footprints in the Blanco River in Central Texas within the Lower Cretaceous that have been identified as foot prints in place. Your foot prints appear to be out of a bed that has been dislocated.
#1 is in place; #s 2, 3, & 4 are weathered out as discrete units and have been displaced.
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