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站在灌溉進水閘旁的男人
20世紀早期，墾務局(Federal
Bureau of Reclamation)的工程師利用水壩及貯水池將乾旱的蛇河(Snake
River)平原變為肥沃的土地
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愛達荷：差異極大的土地
地方性遺產
您曾聽過一座山脈在您眼前長高嗎？那是發生在1983年10月28日，愛達荷境內的第一高山博拉峰(Borah
Peak)在兩分鐘內長高了約八英吋。而在同一時間，沿著26英哩長的洛斯特裡弗嶺(Lost
River Range)奔流的溪水忽然下降了10英呎。您能猜出導致這件事情發生的原因嗎？
這些戲劇性的變化起自一場地震。愛達荷擁有變化極大的地理差異。它是一個地質活躍的地區，它境內涵蓋了冰河、火山及地震，這所有的一切造就出了一個壯觀但惡劣的陸地景色。
冰河移動速度緩慢且會磨蝕山脈。現在博拉峰北部山坡上所殘留的部分奧托冰河(Otto
Glacier)是愛達荷境內唯一的冰河。它及其他的冰河已經在愛達荷境內的高山山脈刨蝕出500多個冰斗(cirques：圓圈的法文字)。當冰河侵蝕山脈並帶走大石塊，就會導致一個由山脈圍成的圓圈，這個圓圈就稱做冰斗；淺的冰斗會變成現在的濕草地，而擁有碗狀底部的深冰斗也許會成為湖泊。
Have you ever heard of a mountain growing right before your eyes? That's what happened on October, 28, 1983, when Borah Peak, the highest mountain in Idaho, grew about eight inches higher in two minutes. Around the same time, the valley floor along 26 miles of the Lost River Range suddenly lowered 10 feet. Can you guess how this happened?
It was an earthquake that caused these drastic changes. Idaho is a state of dramatic geographic contrasts. It is a geologically active region that includes glaciers, volcanoes and earthquakes, all of which have produced a spectacular but harsh landscape.
Glaciers move very slowly and grind away at mountains. The Otto Glacier is the only remaining glacier in Idaho. Only a small remnant of what it used to be exists on the north slope of Borah Peak. It and other glaciers have created more than 500 cirques (French for "circle") in the high mountains of Idaho. A cirque is formed when glacial erosion removes big blocks of rock from mountains, resulting in a circle surrounded by mountains. Shallow cirques appear as wet meadows today, while the deeper ones with bowl-shaped floors may contain lakes.
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關於地方性遺產
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