One burning question has fueled UNLV geologist Peg Rees’s career: Could America and Antarctica be two pieces of the same ancient supercontinent?
Research in the 1980s suggested that theory was possible, with geological findings in rocks found in the Western United States bearing striking similarities to rocks recovered from icy mountaintops in Antarctica.
From 1984 to 1996, Rees completed eight field seasons in Antarctica to test the theory. She was joined by a team of researchers and several mountaineers.
“We were interested in collecting data that would contribute to the understanding of global reconstruction of the earth’s crust between 825 million and 540 million years ago,” said Rees, who retires this month from a 32-year career at UNLV. “The theory was that there was one supercontinent, long before Pangea and before Gondwana. It was called Rodinia, and over the many millions of years, it started to spread apart.”
On her first trip to Antarctica, Rees and her team survived a plane crash. On another occasion, they lived through a helicopter crash.
They were undeterred.
Each season, they climbed the frozen mountain ranges, chiseling samples from rocks and boulders poking through the layers of ice. They would trek up and down the peaks, sometimes five times a day, each carrying 45 to 90 pounds of rocks and soil samples at a time.
In total, Rees’ fieldwork brought some 4,000 pounds of rocks and soil from Antarctica to UNLV. In the labs, Rees and her team examined the materials and compared them with samples from the United States. Their aim was to establish the geological history of the various mountains in Antarctica, from the Holyoake Range and Starshot Glacier to the Northern Churchill Mountains and the Argentina Range.
Rees also was drawn into administrative roles at the university. She rose through the ranks to her most recent posts as vice provost for Faculty Excellence and head of the Public Lands Institute.
As she heads into retirement, she wanted to make sure the collection is available to the next generation of researchers.
On June 29, the stacks that lined the lab at UNLV Paradise Campus were transported to the Byrd Polar and Climate Research Center at Ohio State University, which is home to the National Science Foundation’s U.S. Polar Rock Repository.
Anay Gomez, ’17 BS Earth and Environmental Science, and a research support specialist at UNLV, has spent the past six months cataloguing the vast collection. She examined, labeled, and packed each stone by hand, filling 94 boxes and four pallets.
“This has been a really amazing project,” Gomez said. “To work with a faculty member who has been to Antarctica and recovered all these rocks for us to study, to learn more about how our planet, our home is moving and living — for me, it is a really special experience. Reading through Dr. Rees’ field books, you get a sense that this was really hard work.”
Gomez said working with the rocks from Antarctica has been a deeply moving experience – for her mind and her muscles.
“Each one of these rocks passed through my hands at least once,” she said.
The NSF set up the repository because geological field expeditions in polar regions are logistically difficult, financially expensive, and can have a significant environmental impact on pristine regions. The scarcity of outcrop in Antarctica (98 percent ice-covered) makes previously collected rock samples valuable to the science community.
Rees’ collection is particularly notable for its sedimentary basement rocks from the Transantarctic Mountains and the Ellsworth Mountains, said Anne Grunow, senior research scientist and curator at the Polar Rock Repository
“Few expeditions have revisited the areas that Peg worked in, so the samples represent a unique collection for scientists from around the world to access,” Grunow said. “Peg’s samples have been so well documented that few collections out of the 48,000 samples at the repository will be as detailed as hers, making them especially valuable to future research efforts in Antarctica.”
They will now be incorporated to repository’s inventory of rock, dredge, and terrestrial core samples from polar areas. Experts there curate geological samples collected primarily from Antarctica and the southern oceans, providing full and open access to both samples and metadata on its website.
Rees said she is pleased the collection is catalogued and available for continued research.
“Since I first started my research, technology has really changed,” she said. “Taking another look will refine our knowledge. I think there’s a lot more to the story in these rocks.”