With the help of cutting-edge technology, researchers in Arkansas are unveiling new information about the dinosaurs that existed there 120 million years ago.
What looked like giant potholes in the middle of bedrock terrain in southwest Arkansas has been uncovered as fossilized dinosaur tracks. Now thanks to high-tech light scanner technology, scientists from the University of Arkansas are learning more about the biomechanics and behaviors of the extinct species that once occupied the area by taking 3-D images to record the tracks.
Covering an area of about two football fields, the region is rich with fossilized tracks of several species and animals – some of which have never before been documented in Arkansas. Learning more about the tracks will not only give researchers better clues about dinosaur behavior, it will also provide information about the climate during the Early Cretaceous period 115 million to 120 million years ago.
In addition to chisels, handheld brooms and plaster, light detection and ranging (LiDAR) technologies are being used to map the site.
“It’s critical to scan and document these tracks because once you expose the stone, it will erode away,” said Malcolm Williamson, a researcher from the department of geosciences and the Center for Advanced Spatial Technologies at the University of Arkansas. “In the past, people would take photographs to document site areas and tracks, but the dimensions aren’t always accurate and it’s hard to capture a lot of the details.”
“It’s not practical to preserve the site, so it’s important to document it before it’s lost,” Williamson told TechNewsDaily.
To map the area, Williamson attached a Z+F Imager 5006i scanner, which emits a constant beam of laser light, to a cherry picker. The device then swept across the landscape to measure and record data up to 500,000 points for each second. [Read: 10 Inventions That Were Ahead of Their Time ]
The second unit, used to record an overview of the site from above, is a time-of-flight scanner called Leica ScanStation C10. It incorporates discrete pulses of laser light at a rate of 50,000 for each second, recording a point for each in space. This allows researchers to study a three-dimensional “point cloud” representing the tracks.
With these tech tools, the researchers can view a highly accurate map of the site’s dinosaur tracks and take detailed measurements of the height, width and depth of individual tracks, as well as measurements of the trackways. Not only does the technology take precise measurements of the entire area with ease and speed, it also captures minor details of the tracks.
“The technology allows us to see exquisite detail of the bottoms of some of the tracks,” University of Arkansas geosciences professor Stephen K. Boss, who led the National Science Foundation-funded project. “There are things we can see on the computer screen that aren’t visible to the naked eye out in the sun and in the field. We can rotate image angles, change the contrast and analyze the tracks with more perspective.”
The team looks at where the tracks are located in relation to each other: “Some would be in groups and others would be by themselves. Taking these scans helps uncover more information about what the dinosaurs were doing, whether they were chasing or hunting or just walking along,” Williamson added.
The most dramatic tracks at the site are from a three-toed dinosaur, measuring about two feet long by a foot wide. The researchers believe the footprints might belong to Acrocanthosaurus atokensis, one of the largest predators ever to walk the earth. The site also contains the giant prints of sauropod, which are large, long-necked plant-eating dinosaurs such as Pleurocoelus and Paluxysaurus.
In addition, the tracks help scientists learn information about the frequency of rain and amount of evaporation that once affected the site.
"The air temperature was hot. The water was shallow and very salty,” Boss noted. “Picture an environment much like that of the shores of the Persian Gulf today. It was a harsh environment. We’re not sure what the animals were doing here, but clearly they were here in some abundance.”
Once finished, the data gathered at the site with the help of the laser scanners could potentially be used by paleontologists all over the world, Williamson said.
Reach TechNewsDaily senior writer Samantha Murphy at smurphy@techmedianetwork.com. Follow her on Twitter @SamMurphy_TMN