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詼諧的語言，生動的內(nèi)容一分鐘快速掌握科技最新動態(tài)

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Coldest Glaciers Help Mountains Grow

Glaciers slowly grind their way over mountains and plains, moving immense boulders and carving out fjords. That’s true in temperate regions, where glaciers—glacially—flow downhill. Over thousands of years, the frozen masses can scrape miles off of mountains. Researchers call it the glacial buzz-saw.

冰川沿著山坡、平原一路緩緩磨啊磨，久而久之，礫石易位，峽灣成形。在溫帶確實是這樣，千萬年的時間，冰川能把山頂磨掉數(shù)英里。研究人員稱之為為“冰山鋸”。

But for the very coldest climes, researchers now offer a counter-intuitive view of glaciers – they actually help mountains grow. The finding was published in the journal Nature. [Stuart Thomson et al., IAKcW]

不過，對于寒冷至極的地區(qū)，研究人員倒是提出了反直覺的觀點——冰川實際上有助于山脈增高。該研究發(fā)現(xiàn)刊登于《自然》上。

A team led by scientists from the University of Arizona studied mountains in remote areas of Patagonia in South America.The Andes are actively growing. Hot rocks are shoved to the top, and erosion brings them back down the sides.The team collected 146 samples of rocks from mountainsides and then dated the rocks’ so-called cooling age, which reveals when the rock was exposed by erosion.

在來自亞利桑那大學的科學家的帶領(lǐng)下，一支科考隊對南美洲巴塔哥尼亞偏遠地區(qū)的山脈進行了考察?？疾彀l(fā)現(xiàn)，安第斯山脈海拔正上漲。地下貯熱巖先被噴到山頂部，然后又因冰川的侵蝕作用被甩到山坡上?？瓶缄犑占松狡律?46個巖石樣本，并測定了這些巖石的冷卻年代，從而可以了解其由于冰川侵蝕而被暴露的年代。

They found that erosion happened faster in the warmer mountains to the north, and more slowly in the colder mountains in the south. Turns out that when glaciers are cold enough they don’t move much. Instead, they seal the mountains, protecting them from erosion. The scientists call the effect "glacial-armoring": an invaluable assist for peak performance.

研究人員發(fā)現(xiàn)，越往北越溫暖的地方，冰川侵蝕速度較快，而較冷的南方則較慢。也就是說，冷到一定程度，冰川也就不太移動了，反而會冰封山脈，使其不受侵蝕。科學家稱之為“冰川護甲”：山脈增高的大功臣丫~

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