Aug. 30, 2006 — A 30-mile maze canyons in Antarctica was carved out of bedrock by the catastrophic draining of subglacial lakes during global warming between 12 million and 14 million years ago, according to university researchers who warn a similar event today could have serious environmental consequences.
Although scientists have previously theorized that the Labyrinth region in southern Victoria Land was created by water released from lakes that had formed under glaciers, researchers at Syracuse University and Boston University say they found geological evidence to bracket the timing of the last major flooding and link it to a global warming trend at the time.
The scientists pinpointed the timing of the last subglacial flood by dating volcanic ash preserved on bedrock surfaces, said Laura Webb, a professor of earth sciences at Syracuse who took part in the study.
The Labyrinth is a network of ice-free bedrock channels and scoured terrain emerging from beneath the East Antarctic Ice Sheet. It is one of a series of large channel networks that cross the Transantarctic Mountains.
Some of the chasms are up to 800 feet deep and thousands of feet wide. Scientists have long speculated that the volume of water required to create the channels was far more than that produced by melting glaciers.
Webb said it appeared the subglacial flooding was not continuous but episodic, and likely lasted days or months at a time.
In an article on the study that appeared last month in the journal Geology, Webb and her colleagues estimated the flood raged with approximately 1,000 times the volume of water flowing over Niagara Falls. At that rate, it would take Lake Ontario, for instance, about a month to drain, she said.
Suzanne Baldwin, another Syracuse professor who was one of the study's principal researchers, warned that the ancient episode has implications for global climate change today.
