NEW HAVEN, Conn., Sept. 15 (UPI) — Glaciers, long believed responsible for eroding and wearing down the Earth’s mountain ranges, can actually encourage mountain growth, U.S. researchers say.
Scientists at Yale University say glaciers in the southern Andes in South America may have in fact acted as a kind of protective shield during the mountain range’s 25 million-year history, a university release said Wednesday.
Until now, scientists thought glaciers always erode mountains. Above the tree line, where glaciers remain permanently frozen, scientists believed the masses of ice carve away at the mountain face as they slide down its surface — an idea known as the “buzz saw theory.”
But in the southern Andes, researchers say, they found just the opposite.
Rather than carving away at the mountain peaks, the glaciers instead seem to have helped the mountains grow.
“The glaciers act like armor to protect the uplifting mountains from erosion, allowing them to reach heights well above those predicted by the glacial buzz saw theory,” Yale geologist Mark Brandon said.
In the far southern Patagonian Andes the glaciers remain cold enough that their bases are frozen and stuck to the mountain surface, Brandon said.
Whereas warmer glaciers melt at their base and slide down the mountain, these colder glaciers appear to have provided an icy shield, he said.
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