At the heart of the harsh, unforgiving continent of Antarctica lies a mysterious “ghost” mountain range, the Gamburtsev Mountains, which rivals the European Alps in size. Despite its dramatic size, nobody has ever laid eyes on this enigmatic landscape because it is concealed beneath five kilometers (three miles) of ice.
Their existence first came to light in the 1950s when a group of Russian explorers recorded unusual gravity fluctuations radiating from beneath the thick ice, but it was not until 60 years later that their bizarre characteristics became apparent. After spending four weeks flying ice-penetrating radar instruments across the range, scientists revealed the mountains’ strikingly youthful appearance.
Millions of years of erosion by the grinding ice should have softened the landscape’s sharp features, but instead scientists were presented with rugged crags resembling the Rockies, which are nearly 200 million years younger. So what is the secret to maintaining this youthful appearance? According to a new study, rather than speeding up erosion, the mantle of ice that cloaks this landscape actually helped preserve the mountains’ chiseled features.
“The ice sheet acts like an anti-aging cream,” lead author Timothy Creyts said in a news release. “It triggers a series of thermodynamic processes that have almost perfectly preserved the Gamburtsevs since ice began spreading across the continent.”
As described in the journal Geophysical Research Letters, snow falling on the blanket of ice causes colder temperatures to penetrate downward, towards the mountain peaks. Meanwhile, heat emanating from underlying bedrock causes ice within deep valleys to melt, forming a network of lakes and rivers at the bottom of the mountains. This flowing water is actually forced uphill because of high pressures from the overlying ice sheet, so as it courses up the valleys, it eventually meets colder temperatures from above and refreezes. The resulting thin layer of frozen water is sufficient to shield the ridgeline from erosion.
According to the researchers, this mechanism could also be at play at the Torngat Mountains in eastern Canada and the Scandinavian Mountains that sprawl across Norway, Sweden and Finland. This would therefore explain why some of the ridgelines within these ranges also appear to have defied aging, despite being buried under thick ice during the last ice age.
[Via the Earth Institute at Colombia University, Geophysical Research Letters and Live Science]
