There are about thirty active ones on the Earth at the moment, and they are responsible for many of the world's best known islands and island chains, 眼下，地球上大约有30处活热柱，世界上许多有名的海岛和群岛都与热柱有关，

　　Iceland, Hawaii, the Azores, Canaries, and Galapagos archipelagos, little Pitcairn in the middle of the South Pacific, and many others, 比如冰岛、夏威夷群岛、亚速尔群岛、加那利群岛和加拉帕戈斯群岛，南太平洋中部小小的皮特凯恩岛，以及许多别的岛。

　　but apart from Yellowstone they are all oceanic. 但除了黄石公园以外，别的都在海洋里。

　　No one has the faintest idea how or why Yellowstone's ended up beneath a continental plate. 谁也不知道黄石公园最后怎么或为什么会在陆块上面。

　　Only two things are certain: that the crust at Yellowstone is thin and that the world beneath it is hot. 只有两个情况是肯定的：黄石公园所在地壳很薄，下面的世界很热。

　　But whether the crust is thin because of the hot spot or whether the hot spot is there because the crust is thin is a matter of heated (as it were) debate. 但是，到底是不是因为有了热点地壳才薄，还是因为地壳薄才有了热点，这是个争论很激烈（可以这么说）的问题。

　　The continental nature of the crust makes a huge difference to its eruptions. 地壳的大陆性质对热点的爆发有着重要的影响。

　　Where the other supervolcanoes tend to bubble away steadily and in a comparatively benign fashion, Yellowstone blows explosively. 别的超级火山往往汩汩细流，比较温和，而黄石火山爆发起来非常猛烈。

　　It doesn't happen often, but when it does you want to stand well back. 这种事情不常发生，但一旦发生，你还是离得远一点为好。

　　Since its first known eruption 16.5 million years ago, 据知，它的第一次喷发是在1650万年以前。

　　it has blown up about a hundred times, but the most recent three eruptions are the ones that get written about. 自那以来，它已经喷发了大约100次，但最近的3次是有文字记载的。

　　The last eruption was a thousand times greater than that of Mount St. Helens; 最后一次的强度相当于圣海伦斯火山的1000倍；

　　the one before that was 280 times bigger, and the one before was so big that nobody knows exactly how big it was. 前一次相当于280倍；再前一次的强度大得天知道是多少倍，

　　It was at least twenty-five hundred times greater than St. Helens, but perhaps eight thousand times more monstrous. 至少是圣海伦斯火山的2500倍，但也许是可怕的8000倍。