Hawaii's Next Island
下一个夏威夷超级火山
Look at a map of Hawaii and you'll seevolcanic islands strung outlike pearls on a necklace. The biggest–and theyoungest–is Hawaii, in thesouth-east corner.
随便翻看一张夏威夷的地图,你会发现夏威夷的火山岛分布得就像串在一条项链上的一颗颗珍珠一样。其中威力最大——也是最年轻的火山,当属夏威夷东南角的夏威夷火山。
As the islands stretch away to thenorth-west they become olderand more worn. While Hawaii is about a millionyears old, the extinctvolcano ofKauai on the north-west end is five timesolder.
随着岛屿不断地向西北方向延伸,各大火山变得越来越陈旧,破败。虽然说夏威夷已历经了一百万年的岁月,但是,在西北端考艾岛的死火山却已是其五倍了。
The Hawaiian islands were formed by whatgeologists call “hot spot”volcanos. These occur where hot magma from theEarth's liquid mantle issteadily forced through the Earth's crust.
夏威夷群岛是由地质学家们所称的“火山热点”组成。“火山热点”处在由地幔(又称软流层,很可能是岩浆的发源地)产生的炽热的岩浆不断地被喷出地壳的地方。
Hot spots can last for millions of years,staying in the sameplace while the plates of the Earth's crust move graduallyoverhead.
“火山热点”能持续活动数百万年。就算是地壳板块活动而渐渐居于其上,“火山热点”也一直都不会改变地方。
The plates of the Earth's crust move atuneven speeds, so when theplate moves slowly, this allows a tremendous volcanoto build up. That's why weget a string of separate volcanos, rather than acontinuous line.
地壳板块不是以均匀速度移动的,因而,当板块运动较慢时,一个巨大的火山就可“趁机”形成。这就是为什么火山是一个单独的火山,而不是一片连续不断的火山了。
This is exactly what's happened with theHawaiian islands. The hotspot stayed in the same place, pushing up a string ofvolcanos as the Earth'scrust moved over it.
在夏威夷群岛上也就是如此。“火山热点”一直在某个地方,在地壳板块对其作用时形成了一座又一座的火山。
Because of this, the volcano on north-westKauai is old andextinct, while the volcanos on Hawaii's south-east edge are themost active inthe world.
因此,西北端考艾岛上的火山都是很老的死火山,然而,位于夏威夷东南边的火山却是世界上活动最频繁的活火山。
The Hawaiian hot spot is now located aboutseventeen miles off thesouth-east coast of Hawaii. There's nonew island there,but thereis a huge, underwater volcano, rising almost three miles above theocean floor.
而今,夏威夷的“火山热点”位于夏威夷东海岸约17英里的地方。目前,那里还没有新的岛屿形成,但是那里有一座很大很大的海底火山,高出海底足有三英里高。
Thisnew volcano will break the ocean'ssurface in about fifty thousand years,giving us our next Hawaiian island.
在未来的五万年里,这座新火山将会使海底地壳断裂,创造出下一个夏威夷火山。