万物简史 第324期:美丽而危险(7)（在线收听） |
All this was hypothetically interesting until 1973, when an odd occurrence made it suddenly momentous: 这一切都很有意思，但都是假设的。直到1973年，一件怪事发生了，突然之间那个假设变得很有意义： water in Yellowstone Lake, in the heart of the park, began to run over the banks at the lake's southern end, flooding a meadow, 黄石公园中央的黄石湖水开始溢出该湖南端的堤岸，淹没了一处草地；
while at the opposite end of the lake the water mysteriously flowed away. 与此同时，该湖另一端的湖水神秘地流失了。
Geologists did a hasty survey and discovered that a large area of the park had developed an ominous bulge. 地质学家们马上进行考察，发现情况不妙，公园的一大片地区鼓了起来。
This was lifting up one end of the lake and causing the water to run out at the other, 这种把湖的一头抬起，让水从另一头流出的情景，
as would happen if you lifted one side of a child's wading pool. 如同你抬起孩童的嬉水池的一边会发生的情景。
By 1984, the whole central region of the park—several dozen square miles, 到1984年，公园的整个中心地区——100多平方公里，
was more than three feet higher than it had been in 1924, when the park was last formally surveyed. 比在1924年对公园作最后一次正式勘测时高了1米多。
Then in 1985, the whole of the central part of the park subsided by eight inches. 接着，1985年，公园的中心地区下陷了20厘米。
It now seems to be swelling again. 现在，这个地区似乎又在鼓起来。
The geologists realized that only one thing could cause this—a restless magma chamber. 地质学家们认为，出现这种情况只有一个原因——一个活跃的岩浆房。
Yellowstone wasn't the site of an ancient supervolcano; it was the site of an active one. 黄石这地方古代没有超级火山，只有一座活火山。
It was also at about this time that they were able to work out 也是大约在这个时候，他们推算出来，
that the cycle of Yellowstone's eruptions averaged one massive blow every 600,000 years. 黄石火山平均每60万年大规模喷发一次。
The last one, interestingly enough, was 630,000 years ago. 最近一次喷发是在63万年以前。
Yellowstone, it appears, is due. 黄石火山似乎到了该喷发的时候了。 |
| 原文地址：http://www.tingroom.com/lesson/syysdw/wwwjs/418670.html |