February 2, 2013
Goddard’s Dinosaur Footprints Take Another Step In The Right Direction
[ Watch the Video: Cretaceous Footprint Found on Goddard Campus ]
April Flowers for redOrbit.com - Your Universe Online
In August 2012, well-known dinosaur hunter Ray Stanford brought one track to the attention of the center and the public. As redOrbit's Michael Harper reported, "In a beautiful bit of juxtaposition which can only happen naturally and organically, this Nodosaur print was found on the grounds of NASA´s Greenbelt, Maryland campus. So while 7,000 engineers and scientists are keeping their eyes skyward to discover where our society may one day end up, one man chose to keep his eyes to the ground to discover evidence of the creatures who ruled the Earth millions of years before us; millions of years before something from the sky presumably changed the Earth forever and made way for our existence."
Rob Weems, emeritus paleontologist of the U.S. Geological Survey, and Lee Monnens, Goddard's consultant paleontologist, analyzed the track and discovered the additional footprints hiding under a thin layer of topsoil in the same rock layer.
The footprint-bearing rock was reinforced and removed earlier this year.
“We successfully made a mold of the upper surface to preserve the dinosaur footprints,” said Stephen Godfrey, Curator of Paleontology at the Calvert Marine Museum. Godfrey was contracted by Goddard to preserve and move the footprints for further study. Eventually, the footprints will be on display.
Godfrey confirmed earlier reports that the original footprint was that of a nodosaur.
“This is an armored type of dinosaur that had spikes all over their body. The spikes consist of bones that were embedded in their skin,” he said. “With the second large print, the orientation was different, and the shape of the print is different as well.”
The second creature, Godfrey suggests, was a three-toed ornithopod, perhaps from the iguanodontid family of dinosaurs. Ornithopods were herbivores like the nodosaur. Ornithopods include the Iguanadon, one of the earliest discovered species, and the duck-billed hadrosaurs.
Superimposed over the original nodosaur track was a third, smaller footprint, which experts say is likely a juvenile nodosaur following behind its parent on a more circuitous route.
An iron-rich mineral called hematite was precipitated into the tracks by single-celled organisms feeding on nutrients in the Cretaceous mud. The hematite hardened and preserved the tracks until natural processes buried and fossilized them.
According to Bureau of Land Management (BLM) guidelines, excavation of the stone with the dinosaur footprints had to wait until geologists and paleontologists learned more about the find and the surroundings.
Goddard scientists used ground-penetrating radar in December 2012 to show that the sedimentary rock layer bearing these prints was preserved in its original location. The investigation found no additional indications, however, of locations of dinosaur track specimens of scientific value.
Godfrey, along with volunteers from Goddard, performed more hands-on exploration in mid-December 2012, digging in several areas around the initial find location. They did not turn up any additional preserved footprints.
The entire find is approximately seven feet long and three feet across at its widest point, containing at least three dinosaur footprints. This layer is bonded to a separate layer of iron-rich sandstone, which complicated the efforts to extract and preserve it.
Before beginning the extraction process, Goddard made a silicon-rubber cast of the prints. The entire find was then jacketed in multiple layers of plaster-soaked burlap, much like a cast on a broken limb. This added rigidity to the stone layer to further ward against breakage during transport. To act like splints, galvanized steel pipes were wrapped into the jacket to provide additional structural support.
The entire structure — footprint laden rock, jacket material and surrounding soil — had a combined weight of approximately 3,000 pounds, necessitating extra care when moving it to avoid damaging the rather extraordinary find.
Senior management at Goddard will work with government officials and scientists to determine the final disposition of the dinosaur-track-bearing rock layer.
"One of the amazing aspects of this find is that some of the starlight now seen in the night sky by astronomers was created in far-distant galaxies when these dinosaurs were walking on mud flats in Cretaceous Maryland where Goddard is now located," said Jim Garvin, Chief Scientist at NASA Goddard. "That starlight (from within the Virgo Supercluster) is only now reaching Earth after having traveled through deep space for 100 million years."
Center Director Chris Scolese added, "Much of the work at Goddard is focused on Earth and space science. The discovery and follow-on work with the dinosaur footprints created a wonderful blending of sciences. You have astronomy - the study of the Universe, geology - the study of the Earth, and paleontology - the study of the prehistoric life on Earth and they have all come together here at NASA Goddard."