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地球 四百五十亿年历史的古老行星 Earth, a 4.5 billion year old planet,
仍在不断地进化 still evolving.
随着大陆板块的漂移与撞击 As continents shift and clash,
火山爆发 以及冰川的形成与消融 volcanoes erupt, and glaciers grow and recede,
地壳被雕刻成了无数神奇的形状 the Earth's crust is carved in numerous and fascinating ways,
留下了一串地质学谜题 leaving a trail of geological mysteries behind.
这一集 In this episode,
我们将带您探索世界上最大的火山岛屿 Iceland, the world's largest volcanic island,
冰岛 is explored.
这片贫瘠而又陌生的土地 This barren and alien landscape
制造了地球上三分之一的火山岩 generates one third of the world's lava.
蒸气从地表喷薄而出 Steam billows from the ground
沸水直冲云霄 and boiling water is thrust into the air.
这是一片充满剧烈碰撞的土地 It's a land of violent extremes
冰与火在此交锋 where fire meets its nemesis, ice,
在这里 理解冰岛形成的各种线索 and where clues to understanding Iceland's formation
同样也是理解地球如何形成的一个视角 also provide a window into the formation of the Earth itself.
历史频道
地球
起源
冰岛
冰岛位于北大西洋的中心 In the middle of the north Atlantic Ocean lies Iceland,
是一座仅有三百英里宽的孤岛 a lone island, only 300 miles wide.
这里火山纵横 A volcanic hotbed,
拥有人类所知道的最多样的地理奇观 it holds some of the most diverse geological wonders known to mankind.
为了理解冰岛的形成 To understand how it formed
以及形成该岛的动力 and the dynamic forces that are shaping this land,
科学家们探索奇特地貌 寻找各种线索 scientists are scouring the strange landscape for clues.
冰岛的调查开始于此 And the investigation starts here,
辛维里尔平原
冰岛西南部的辛维里尔平原 in the southwest of Iceland - the Thingvillir plain.
这条广阔的内陆峡谷横穿冰岛中心 This broad inland valley runs through the center of Iceland.
巨大的裂缝深入谷底 Giant cracks scar the valley floor,
形成了如此奇特的地貌景观 leaving this unusual landscape behind.
地理学家迈克·波兰德相信 Geologist Mike Poland believes
这些裂缝是揭开冰岛形成之谜的主要线索 they're a major clue in the mystery of Iceland's formation.
在我脚下 是一片神奇的土地 I'm standing in a really spectacular place.
这里到处都是火山活动的证据 There's evidence for volcanic activity all around.
被火山岩所覆盖着的峡谷 This valley is covered in lava
将平原分割的支离破碎 and the plain is being ripped apart.
放眼望去 地面上有很多巨大的裂缝 Everywhere I look, there's massive tears in the ground,
就像我眼前的这条一样 like this one right here.
这条裂缝每年都在变大 This crack is getting bigger and bigger every year.
事实上 整个峡谷正在以 In fact, this entire valley is spreading apart
与指甲生长相同的速度 相互分离开来 at about the same rate that fingernails grow.
现在 让我们来想象一下 Now, imagine the forces
若想像这样撕裂陆地 that must be involved
究竟需要怎样的力量才能够实现 to rip the land apart like this.
某种强大的力量 正使得这座峡谷 Something powerful is spreading this valley
以每年一英寸的速度 相互分离 at a rate of one inch a year.
这个力量非常巨大 A force so immense,
甚至正在将整个国家撕裂开来 it's pulling the entire country apart.
然而究竟是什么力量 But what force on Earth
能够造成如此巨大的影响呢 could have such power?
一九一二年 德国气候学家 In 1912, German climatologist
阿尔弗雷德·韦戈纳发现了一条重要线索 Alfred Wegener found an essential clue.
通过观察地图 他发现 Browsing through maps, he noticed that
美洲大陆板块与欧亚大陆板块 the great land masses of the Americas and Eurasia
似乎能够拼接在一起 appeared to fit together.
韦戈纳根据这个发现 This observation led Wegener
提出了一个激进的新理论 to propose a radical new theory,
这便是 所有大陆都曾彼此相连 that these great continents had once been joined together.
所以一定存在着某种看不见的力量 So some unseen force
将它们彼此分离 must have pushed them apart,
使得海水涌入它们之间的空隙 allowing water to rush into the space between them,
形成大西洋 creating the Atlantic Ocean.
这是令人鼓舞的开创性的研究 It was inspired detective work
同样也是探索冰岛分裂原因的 and a major step forward in the search for
一个重大进展 what was pulling Iceland apart.
但由于无法证明这种力量的存在 But with no method to prove such a force existed,
韦戈纳的理论在随后的四十年里 Wegener's theory was ignored
并未被广泛接受 for the next 40 years.
直到一九四六年 人们发现了新的证据 Then, in 1946, new evidence was discovered
支持了韦戈纳的理论 to support Wegener's ideas.
美国海军通过应用声波成像技术 The US Navy, using a technology called sonar imaging,
首次绘制出了大西洋海床的地形图 mapped the Atlantic Ocean floor for the first time.
地图上显示出了 The pictures revealed
一座长达一万英里的水下山脉 a 10,000-mile network of underwater mountains,
这座山脉被穿过大西洋中心的 separated by a giant tear
一条巨大裂缝所割裂 which passes through the center of the Atlantic.
科学家们称之为中大西洋海岭 Scientists call this the Mid-Atlantic Ridge.
这条贯穿地壳的巨大裂缝 This huge tear through the Earth's crust
是美洲版块与欧亚版块的分界线 is the boundary between the American and Eurasian plates,
而这条裂缝也恰好穿过冰岛的中央 and the tear runs right through the center of Iceland.
实际上 我正站在海床之上 I'm actually standing on what's essentially the ocean floor
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美国地质调查 地质学家
迈克·波兰德博士
这是中大西洋海岭露出海面的部分 where the Mid-Atlantic Ridge comes onto land.
而中大西洋海岭将北美版块分往这边 And it splits the North American plate on this side
将欧亚版块则分往这边 from the Eurasian plate on this side.
中大西洋海岭开始于南边的南极洲 And the Mid-Atlantic Ridge starts way south down by Antarctica,
一路向上 穿过大西洋 comes all the way up through the Atlantic
将冰岛一分为二 and splits this country right in two.
科学家们觉得这便是导致大陆版块 Scientists suspected this was pushing the continents,
和冰岛逐渐分离的原因 and Iceland, apart.
他们提出了一种理论 They came up with a theory.
大洋深处 Deep below the ocean,
熔岩的对流运动导致地壳出现裂缝 convection currents of molten rock tear open the Earth's crust,
使得岩浆从此处渗出 将大陆彼此推离 allowing magma to seep up and push the continents apart.
但这里有个问题 But there was a problem.
由于所处位置过深 It was so deep,
科学家们无法证明 scientists had no way of proving
在海岭的中央是否有岩浆渗出地壳 whether magma was seeping through the crust at the center of the ridge.
直到一九七四年 Until, in 1974,
伍兹·霍尔海洋学研究所 Alvin, a human-operated submersible,
派出一艘名为艾尔文的人工驾驶深潜器 was launched by the Woods Hole Oceanographic Institute.
由于深潜器能够承受深海压力 With its ability to withstand deep sea pressures,
科学家们最终得以下潜到 scientists could finally travel down
所需的深度 去探索中大西洋海岭 to the depths needed to reach the Mid-Atlantic Ridge.
通过研究穿过这条海岭中央的裂缝 It was by examining the tear that runs through the center of this ridge
科学家们找到了他们寻觅已久的证据 that they spotted the evidence they'd been looking for -
即喷进大海的炽热火山气体 hot volcanic gases billowing into the ocean.
这一发现表明 Finding this told them that
中大西洋海岭的火山活动十分剧烈 the Mid-Atlantic Ridge was highly volcanic
像一把巨大的楔子 and, like a giant wedge,
将连在一起的大陆版块分开 was capable of spreading great land masses apart.
冰岛的辛维里尔裂谷 Iceland's cracked Thingvillir valley
是中大西洋海岭的延伸 is a continuation of the Mid-Atlantic Ridge.
美洲与欧洲逐渐分离的过程 The same process that's pushing America further away from Europe
也同样发生在这片陆地上 is happening here on land.
最终 这种强大的力量足以解释 Finally, here was a force powerful enough to explain
裂缝逐渐加宽和冰岛逐渐变大的原因 why the cracks are getting wider, and Iceland is getting bigger.
随着海岭不断分离 As the ridge continues to spread
冰岛的面积也逐渐扩大 it's going to add, more and more land to Iceland.
因此从某种程度上来说 So, in a way Iceland will start getting longer and longer
随着大陆版块彼此分离 uh, in an east-west sense
冰岛也将会在东西方向上变得越来越长 as the plates spread apart from one another.
所以从这个方面来讲 So in a way,
冰岛并不是被分裂开了 Iceland is not getting torn apart
而是在不断扩建 so much as it's getting built.
对冰岛如何扩张的研究表明 The investigation into how Iceland is growing has revealed
辛维里尔平原上的裂缝 cracks on the Thingvillir Plain
正在以每年一英寸的速度加宽 are widening at a rate of 1 inch a year.
炽热的气体表明 And hot gases prove
这种分离的力量来自于火山活动 that this spreading force is volcanic,
从而形成了恰好割裂冰岛的中大西洋海岭 forming the Mid-Atlantic Ridge which cuts right through Iceland.
科学家们确信这正是冰岛逐渐扩大的原因 Scientists concluded it's this that's widening the country.
熔岩的对流运动将中大西洋海岭逐渐分离 Convection currents of hot rock pull the Mid-Atlantic Ridge apart.
岩浆奔涌而出 填满了裂缝 Magma surges up to fill the cracks and,
当它到达地表时 as it approaches the surface,
会冷却 固化 然后形成新的陆地 it cools, hardens and forms new land.
这个过程就像是传送带一样 Like a conveyor belt,
不断将冰岛分裂 it continually pushes Iceland apart.
但有些事情却无法解释 But something didn't add up.
为什么冰岛不像中大西洋海岭的 Why wasn't Iceland at the bottom of the ocean
其他部分那样 位于海底呢 like the rest of the Mid-Atlantic Ridge?
这座岛屿上的火山活动数量 There's something strange about
异于寻常 the amount of volcanic activity on this island.
这里是中大西洋海岭的一个特殊区域 This is not a normal section of the Mid-Atlantic Ridge.
海岭的这一部分所发生的火山活动 There's a tremendous amount of volcanism
数量非常巨大 that's happening in this part of the ridge.
相反 海岭在大西洋中则安静的多 As opposed to the ridge that's off in the Atlantic Ocean.
接下来 我们将继续探索 The hunt is now on to discover
冰岛是如何从海底升高一点五英里的 how Iceland rose a mile and a half off the ocean floor
又如何变成了世界上最大的火山岛屿 and became the biggest volcanic island in the world.
冰岛 Iceland.
这里集中的活火山数量 There are more active volcanoes concentrated here
比地球上其他任何地方的数量都要多 than anywhere else on the planet.
地理学家们正在探索 Geologists are searching for
究竟是什么将冰岛推离了海底 what has helped push Iceland off the ocean floor
又是什么导致了火山活动 and lights the fiery volcanoes
在这片贫瘠的土地上 如此活跃 that rage across this barren land.
为了寻找答案 我们登上了 On the hunt for clues, the investigation heads to
冰岛最活跃的火山 赫克拉峰 one of Iceland's most active volcanoes, Hekla,
当地人称其为地狱之门 known locally as the Gateway to Hell.
与冰岛上的其他活火山一样 Like all active volcanoes in Iceland,
赫克拉
赫克拉正好位于中大西洋海岭的边缘 Hekla sits alongside the Mid-Atlantic Ridge.
火山学家皮特·拉费米纳博士 Volcanologist Dr. Pete La Femina
正在对赫克拉峰进行高分辨率扫描 is taking a high-resolution scan of the volcano
以探查该火山的地质情况 to see if its geology
是否掩盖了关于火山内部活动的线索 hides any clues about its inner workings.
这台陆地激光扫描仪 This is a terrestrial laser scanner,
激光会产生地表的三维图像 and the laser produces a 3-D image of the Earth's surface,
使我们能够观察肉眼无法看到的 and that allows us to see parts of Hekla volcano here
赫克拉火山的部分活动 that we can't see with the naked eye.
他的扫描图像显示出了一条巨大的裂痕 His scan reveals a giant crack,
或者说 裂缝 or fissure,
正好穿过火山的中心区域 running right through the center of the volcano,
与在辛维里尔峡谷所发现的那些裂缝类似 similar to those found in the Thingvillir valley.
但这条裂缝并不只是贯穿整座火山 But this fissure doesn't just span the width of the volcano,
它还向两端延伸 it extends either side,
紧靠着地上的一条长达五英里的裂缝 along a five-mile tear in the Earth.
这条裂缝正是理解冰岛的火山 It's this tear that's key to understanding
如何爆发的关键 how Iceland's volcanoes erupt.
赫克拉火山在两千年喷发的时候 When Hekla erupted in the year 2000,
爆发的并不仅仅是火山锥 it wasn't just the volcanic cone that exploded.
地球实际上是被沿着 The earth actually ripped open
整条五英里长的裂缝撕开了 along the entire five-mile length of the fissure,
而该裂缝正是沿中大西洋海岭拉伸的结果 a weakness created by the stretching along the Mid-Atlantic Ridge.
地质学中将此现象称为 裂缝喷发 In the geological world, these are known as fissure eruptions.
大量岩浆从地下涌出 致使裂缝打开 Forced open by the sheer volume of magma pushing up from below,
一小时内喷出了可怕的 the tear spewed out a terrifying
七百五十亿立方英尺熔岩 750 million cubic feet of molten rock an hour,
将大地吞噬 flooding the land with lava.
裂缝喷发的能量巨大 These fissure eruptions are so huge
它们可以在数日之内极大地改变地表形态 they can change the landscape drastically in a matter of days,
形成眼前这般的山峰 leaving behind mountains like these.
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宾州大学
皮特·拉费米纳博士
你可以看到北边这里 You can see to the north here
这里的地表在裂缝喷发 where the Earth's surface actually opened up
熔岩喷出的过程中 实际上是张开的 during the fissure eruption and lava erupted out.
这条裂缝从北面那里开始 This fissure starts to the north
延伸八公里 穿过这里的赫克拉火山 and extends eight kilometers through Hekla volcano here.
在赫克拉火山这里 The sheer volume of magma produced
可以清楚地看到 大量喷出的岩浆 can be seen very well here at Hekla volcano,
特别是这些覆盖地表的熔岩流 especially with these lava flows that have draped the land's surface.
这让我感到很兴奋 And, to me, this is really exciting
你可以看到 在极短的时间里 because you can see very large volumes of eruptive material produced
产生了大量的喷发物质 over very short amounts of time.
而赫克拉则是研究该现象的最佳选择 And Hekla is--is a beautiful place to study that.
但又是什么 在喷发过程中 But what is creating the vast quantities of lava that are forced out
制造了如此大量的熔岩呢 during these eruptions?
多年来 这个问题一直都没有定论 For many years, the answer remained elusive,
直到地质学家们在岩石内部 until geologists found incriminating evidence
找到了相关的证据 locked inside the rocks.
冰岛的岩石成分 The composition of the rocks here in Iceland
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地质学家 美国地质调查
迈克·波兰德博士
与别处的不太相同 is quite different than we see in other places.
将这里的岩石带回实验室去研究 By taking this rock back to the lab,
我们能够了解 we can get a very good idea of
这些岩石是在何种条件下形成的 under what conditions it formed,
是在地球深处形成的 whether it formed deep within the Earth
还是在地表附近形成的 or--or near the surface.
这块岩石曾是冰岛的某座火山喷发 This rock was once molten lava
所带出的熔岩 which erupted from one of Iceland's volcanoes.
岩石的化学成分分析显示出了 Analysis of the chemicals in the rock revealed
极高浓度的稀土元素 unusually high concentrations of rare Earth elements,
镧和铯 lanthanum and cesium,
它们只会存在于超深源的岩浆之中 chemicals which are only found in magma with a very deep origin.
这是取得突破的科学家们 It's the breakthrough scientists
一直想要探寻的结果 had been searching for.
它表明 It was evidence
另一个更深的热源 that another, much deeper, heat source was combining
和中大西洋海岭一起 with the Mid-Atlantic Ridge
为冰岛的火山活动提供动力 to power the volcanoes of Iceland.
岩石证据表明 The rock evidence suggested
这第二种力量深处于 this second force lay hidden from view,
我们无法看到的冰岛地表之下 deep beneath Iceland's surface,
但我们仍能够一探其活动情况 but it is possible to get a glimpse of what's happening down there.
科学家们在全球监测 Scientists monitor the seismic waves triggered
由地震活动所引发的震波 by earthquakes all over the world.
当地球版块运动时 As the Earth's plates move,
会释放出穿越地壳的 they release shockwaves called seismic waves
叫做地震波的冲击波 that pass through the Earth's crust.
地震波以稳定的速度进行传播 These travel at a steady speed,
但当它们进入熔岩时 传播速度会减慢 unless they hit a region of hot rock, then they slow down.
现在 当地震波到达冰岛 Now, as seismic waves arrive in Iceland,
它们在地表传播非常缓慢 they're traveling very slowly through the subsurface,
这种独特的现象只会出现在冰岛 and this is somewhat unique to Iceland
和世界上少数几个地方 and a few other places in the world.
说明地下会有非常炽热的柱状熔岩 It tells us that there's a very hot column of rock,
甚至有可能是某种熔融物质 perhaps even some--some molten material beneath the surface.
这些巨大的柱状体 或羽状体 These massive columns, or plumes,
就是热点 are known as hotspots,
它们并非冰岛所独有 and are not unique to Iceland.
在世界上某些火山地区的下面 They are found beneath certain volcanic areas
也发现了它们 如夏威夷和黄石公园 in the world, like Hawaii and Yellowstone.
热点就是这些从地球深处向上 Hotspots are these unwavering plumes of--of hot material,
流动到地表的坚固的羽状炽热物质 including molten rock, magma,
包括熔岩 岩浆 that stream up to the surface from deep within the Earth.
科学家们终于对这促使冰岛形成的 The scientists finally had a snapshot of the second force
第二种力量 有了初步的了解 that was helping to create Iceland.
冰岛之下的热点 The hotspot that lies beneath the island
有大约一百英里宽 四百英里深 is almost 100 miles wide and 400 miles deep.
它在超过一千七百华氏度的温度下 It channels rock slowly upwards
缓慢地将岩石向上输送 at temperatures over 1,700 degrees Fahrenheit.
它推挤地壳 从地下烘烤大地 It pushes against the crust, heating the land from below
将岩浆向上推至地表 形成熔岩 and forcing magma up onto the surface as lava.
调查研究确认了冰岛形成的两大力量 The investigation has identified the two colossal forces that built Iceland-
即中大西洋海岭 和冰岛地下热点 the Mid-Atlantic Ridge and the deeper Icelandic hotspot.
数百万年前 中大西洋海岭向东漂移 Millions of years ago, the Mid-Atlantic Ridge drifted eastwards,
渐渐向固定的冰岛热点靠近 creeping towards the fixed Icelandic hotspot.
最终 两种力量合二为一 Finally, they met
以最致命的方式相互合作 and have been locked together in a deadly partnership ever since.
结果 一个绝对令人生畏的火山野兽 The result, a truly formidable volcanic beast,
能够制造出大量岩浆 capable of creating magma on a monumental scale.
随着洋中脊的分裂 As the mid-ocean ridge pulls apart,
在它下面的物质得以减压 there's decompression of the material underneath it
这样便产生了熔化 and that creates melting.
减压就是失去大量岩石所产生的压力 Decompression is simply removing the pressure from a pile of rock.
就像打开罐装苏打水 It's much like opening a can of soda
或拔开香槟瓶上的软木塞 or popping the cork off of a-- a champagne bottle.
巨大压力的缺失使得岩石熔化为液态岩浆 The removal of so much pressure makes the rock melt into liquid magma.
热点直接从地球内部 The hotspot is transporting heat
向地表转移热量 directly from the interior of the Earth to the surface,
同样也能引起熔化 which also creates melting.
所以地下已有岩石的减压 So this combination of decompression of existing rock beneath the surface
与直接来自地心的热量转移相结合 and the direct transport of heat from the center of the Earth
产生了巨量的熔岩 create a huge amount of magma.
中大西洋海岭与热点的神奇相汇 This incredible meeting of the Mid-Atlantic Ridge and hotspot
开始在海浪之下建造岛屿 began to build the island beneath the waves,
并将它向上推送 冰岛便诞生了 pushing it upwards and giving birth to Iceland.
科学家们相信海底岛屿形成于两千万年前 Scientists have dated the island's emergence to 20 million years ago,
但却只能想象出岛屿的形状 but could only imagine what this might have looked like.
然而在一九六三年十一月十四日 But on November 14th 1963,
在位于冰岛南岸的海面上 off the south coast of Iceland,
世界见证了冰岛壮观诞生景象的重演 the world watched an action replay of Iceland's spectacular birth.
滚滚烟尘携带着岩石碎片 冲出洋面 A column of rock and ash blasted out of the ocean,
直达一万八千英尺的高空 18,000 feet into the sky,
甚至远在七十英里外的冰岛首都 so high it could be seen 70 miles away
雷克雅未克 也能够看到 in Iceland's capital city, Reykjavik.
一座新的岛屿就此诞生在世人的面前 A new island was forming right in front of the world's eyes.
科学家根据挪威火神叙尔特尔的名字 Scientists called it Surtsey,
将该岛命名为叙尔特塞岛 after the Norse god of fire, Surtr.
这座距冰岛大陆二十英里远的海中小岛 Located 20 miles off the mainland,
吸引了众多地质学家们前来探究 the small island of Surtsey is now a magnet for geologists.
对研究冰岛最初成因的拉菲米纳博士来说 It offers a wealth of forensic evidence for Dr. La Femina,
它提供了丰富的鉴定证据 who is investigating how Iceland first formed.
首次去看叙尔特塞岛让我很兴奋 It's amazing to see Surtsey for the first time.
我看过它的照片 I've seen pictures.
也看过它的航空摄像图 I've seen aerial photographs.
但真的来到这里 But to actually be here
有机会近距离观察它 and a chance to, uh go out and see it up close
观察它的地质情况 and actually look at the geology
真是让我无比振奋 it's just, awe inspiring.
形成叙尔特塞岛的这种喷发类型 This type of eruption that formed Surtsey
如今被命名为叙尔特塞喷发 has now been named after Surtsey,
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宾州州立大学
皮特·拉费米纳博士
我们把它们叫做叙尔特塞式喷发 we call them Surtseyan eruptions,
这种喷发有很强大的爆发力 and they're very, very explosive.
炽热熔岩或岩浆与海水相互作用 The interaction of hot magma or lava with the ocean
引起了这充满蒸汽 causes these very steam-rich
极具爆发性的烟水混合物的喷发 and highly explosive eruptions of ash and water.
当科学家们在一九六四年夏天 When scientists first stepped foot
首次踏上这座岛屿时 on the island in the summer of '64,
他们难以相信 they found it hard to believe
这座岛屿形成不过数月 that this was an island whose age was measured in months,
而非数千年 not millennia.
在大约九个半月的时间里 In about nine and a half months,
这个火山锥就形成了 this whole volcanic cone built up.
另外 岩浆流沿着火山中心流出 In addition, lava flows came out of the volcanic center here,
形成了我们现在看到的这些漂亮的黑岩 and we're seeing those, these nice black cliffs in front of us.
如今 地质学家们知道了 Now geologists had an insight into
冰岛是如何形成的 how early Iceland might have formed.
在短短两千万年的时间内 In only 20 million years,
冰岛从一座小岛 Iceland grew from a tiny island
变成了一座面积四万平方英里的岛屿 into a 40,000 square mile land mass
与肯塔基州面积相当 as big as the state of Kentucky.
冰岛火山的动力源终于得到确认 The forces that power Iceland's volcanoes have been revealed.
沿着赫克拉火山的裂缝 Cracks along Hekla volcano
释放出大型的裂缝喷发 unleash gigantic fissure eruptions.
岩石中的稀有元素表明 And rare chemicals in the rock prove that
这些喷发是由两种力量所激发的 these eruptions were fueled by two separate forces,
即中大西洋海岭与热点 the Mid-Atlantic Ridge and the hotspot.
冰岛逐渐成为了世界上最大的火山岛 Iceland grew to become the world's largest volcanic island.
但单纯的火山作用并不能解释 But volcanism alone doesn't explain
冰岛上的陆地是如何形成的 how the land of Iceland was formed.
调查还发现了另一种同样重要的力量 The investigation will unearth another, equally dramatic, force
这种力量造就了冰岛今日独特的轮廓 that sculpted the distinctive shape of the Iceland we know today.
它与冰岛火山的力量相抗衡 A force which would challenge the might of Iceland's volcanoes.
如果冰岛只是由火山喷发塑造而成的 If Iceland was formed by fire alone,
那它的形状应该会像诸如夏威夷或塔希提 it should look like other volcanic islands
那样的火山岛 such as Hawaii or Tahiti,
但其他的力量也在这里起作用 but something else was at work here
将这座岛屿改造成今日独特的形状 to transform this island into the distinctive shape it is today.
冰岛的形状是冰岛形成的另一条线索 Its shape is another clue to Iceland's formation.
特殊的力量将冰岛北海岸刻画成锯齿状 An extraordinary force indented Iceland's northern coastline,
形成向内陆延展的深深峡湾 burrowing deep fjords which extended far inland.
但究竟是什么巨大的力量 But what colossal force
使得冰岛的火山地貌 could cause such a dramatic change
发生了如此剧烈的变化呢 to Iceland's volcanic landscape?
当然 我们可以猜想是由于 There's an obvious suspect
岛上散落分布的冰 that's found scattered across the island - ice.
冰岛 正如其名 As its name suggests,
在很长的一段时间内 都被冰雪所覆盖 Iceland has a long history of being covered in ice like this.
如今 岛上十分之一的土地 Today it covers ten percent of the island,
终年被冰雪所覆盖 all year round.
在该国的中央是欧洲最大的冰盖 And in the middle of the country lies Europe's biggest icecap,
瓦特那冰川
即巨大的瓦特那冰川 the mighty Vatnajokull.
瓦特那冰川的面积巨大 Over 3,000 square miles in size,
超过三千平方英里 Vatnajokull is so large
拥有自己的气候环境 it even has its own climatic conditions.
冰盖厚度达到三分之二英里 Up to two thirds of a mile thick,
像一块巨大的厚石板挤压着陆地 it squashes the land like a giant slab of rock,
在其边缘 长长的冰舌伸向深谷 and at its edges, great tongues of ice flow out through deep valleys.
冰川专家马修·罗伯茨博士正在调查 Glacier expert Dr. Matthew Roberts is investigating
冰川是如何凿穿磐石的 how ice can gouge out solid rock,
找出冰盖在冰岛形成过程中所起的作用 and discover the role it has played in Iceland's past.
这是卫星接收器 相当于汽车卫星导航 This is a GPS receiver, just like in car satellite navigation.
这里用它来监测冰川运动 It's used here to measure glacier movement.
将它在冰面上放置几天 This will be left on the ice surface for a few days
之后我会回来 进行数据分析 and then I'll come back and I'll analyze the data
观察冰川运动了多少距离 and discover just how far the glacier has moved.
罗伯茨博士收集的数据表明 Dr. Roberts' data reveals
整个冰川正以每天两英尺的 that this whole glacier is sliding forward
惊人速度向前滑动 at an astounding rate of two feet per day.
这里的环境千变万化 令人惊叹 This is an amazing, ever-changing environment.
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马修·罗伯茨博士
我的周围就像一片凝固不动的冰海 The ice around me is like an icy sea that's been frozen in place.
当冰川从山谷旁流出时 As the ice flows out of the confines of the valley,
它就会迅速扩散 占据更广阔的区域 it expands and spreads to occupy a greater area.
而扩散会导致裂缝的出现 Now, as it expands, crevasses form,
大的裂缝就跟我身边的这条差不多 and large depressions just like the one here.
这条则是形成的较小的裂缝 Here's a smaller crevasse that's formed.
有时 当这些裂缝张开 Occasionally, when these crevasses open,
你能听到开裂的声音 as they begin to open, sounds can be heard.
冰川有时也会发出嘎吱声 Also, the glacier occasionally makes a groaning sound.
这是冰川活跃 This is all signs that the glacier is alive
向前缓慢移动的全部标志 and moving forward very slowly.
瓦特那冰川是北半球最大的冰盖之一 Vatnaj kull is one of the largest icecaps in the northern hemisphere.
随着冰盖从山谷滑下 Flowing down the valleys,
巨量的冰会产生 the great mass of ice bears down
每平方英尺重达百吨的压力 with the weight of 100 tons per square foot.
罗伯茨博士相信这移动的巨型冰川 Dr. Roberts believes this moving giant
正是能够侵蚀磐石的力量 is a force capable of eroding solid rock,
而且他找到了用来证明的关键证据 and he's found crucial evidence to prove it.
这是冰川侵蚀能力的一个很好的例子 This is an excellent example of the power of glacial erosion.
这块大石头曾在冰川之下 This boulder would have been trapped beneath the base of the ice,
当冰从它表面漂过时 and as the ice flowed over the surface of it,
会逐渐侵蚀石头的表面 it would have progressively eroded the surface of the boulder
从而在产生了这些独特的印记 to produce these very distinctive marks
我们将此称之为 表面擦痕 called striations in its surface.
我们甚至能够辨认冰川漂动的方向 We can even tell the direction in which the ice was flowing.
我拿块石头 演示一下 If I take a rock, I can illustrate this.
把这想象作冰川的底部 Imagine this is the base of the-- of the ice
当冰川运动时 and material trapped inside the ice
冻在冰种的物质也会一同运动 is being dragged across as the glacier moved
便会在石头表面产生这些独特的印记 to produce these very distinctive marks in the surface.
就像用砂纸去磨糙木料一样 This is just like sandpaper over wood.
同样的侵蚀效果 The same erosive effect.
在这块石头上发生的侵蚀过程 The erosive process that's happening on this boulder is
也沿着这些峡谷的表面 the same process that's happening on a much larger scale
大规模地发生过 along the surface of these valleys.
这些从前被岩石填满的低谷与盆地 The glacier is responsible for literally carving the landscape,
是如此与众不同 producing very distinctive troughs and basins
这些地貌都出自冰川的鬼斧神工 which were formerly infilled with solid rock.
这显示了冰川巨大的侵蚀能力 This really testifies to the--the erosive power of--of a glacier.
北海岸古老的峡湾有着相同的盆状形态 The ancient fjords on the north coast are the same deep basin shape,
这意味着 那里也曾是冰的世界 which means they must once have been filled with ice.
如今 科学家们了解到 Scientists now know that,
大约一百五十万年前 around one and a half million years ago,
地球轨道的变化以及地轴的倾斜 changes in the Earth's orbit, and the tilt of its axis,
使地球的温度开始下降 began to cool the planet.
从地球北部蔓延开的冰盖 An enormous ice sheet descended from the north
给冰岛披上了一层冰衣 and shrouded Iceland in a cloak of ice.
冰盖的蔓延与消退 As the ice advanced and retreated,
切割出了这些深深的峡湾 it carved out deep fjords
也塑造出冰岛曲折的北海岸线 and indented Iceland's northern coastline.
冰是冰岛上的一股强大力量 Ice was a formidable force in Iceland,
而在它的下面 沉睡着大量火山 and many volcanoes lay entombed beneath it.
冰与火则为争夺霸权 陷入一场鏖战 Fire and ice were now locked in a titanic battle of supremacy.
切割峡湾的巨大冰盖 Would the giant ice sheets that carved the fjords
能扑灭创造冰岛的火焰吗 put out the fires that created Iceland?
第一条线索就藏在冰川以西五英里的 The first clue lies in this ancient valley,
古老的山谷中 five miles west of the glacier.
谷底散布着成百块巨石 The valley floor is strewn with hundreds of giant boulders,
但令罗伯茨博士好奇的是 but it's how they got here
它们是如何到这的 that interests Dr. Roberts.
这些巨石有助于我们深刻理解 These boulders provide a lot of insight into
这种地貌是如何形成的 how this landscape was formed.
巨石聚集在这里 The boulders are clustered together and,
有趣的是 它们都是圆润的 interestingly, these boulders are rounded,
说明它们曾不断翻滚 which shows that they've been rolling.
现在 在某种动力的作用下 Now, the boulders have been brought together
这些巨石 聚拢在一起 by some dynamical force.
你可以看见 中间困着一些较小的石头 You can also see smaller boulders trapped in the center.
很明显 这是水流造成的结果 And It's quite clear that flowing water is the cause of this.
不过这可不是背景中的那种 But this wouldn't have been water in the stream
涓涓细流 that we see in the background.
而是足以淹没整个山谷的迅猛潮水 This would have been water produced by a much larger, faster flow
产生的水流 that would have inundated this entire valley.
罗伯茨博士对于这里所发生的事情 Dr. Roberts has an extraordinary theory
有一套特别的理论 about what happened here.
古时候 一场一百英尺高的大洪水 In ancient times, a cataclysmic flood 100 feet high
贯穿了山谷 cut through this valley.
它威力无比 It was so powerful that
这些巨石就如同溪里的鹅卵石般被卷起 it rolled these giant boulders like pebbles in a stream,
最终被遗弃在这片区域 before dumping them on the landscape.
但这浩大的水流是如何产生的呢 But what could create such a colossal flow of water?
罗伯茨博士认为洪水 Dr. Roberts suspects the flood
产生自巨大的瓦特那冰川 came from the mighty Vatnaj kull glacier
而他也正要去寻找线索 and is hunting for clues.
由于需要考察一大片区域 With such a huge area to cover,
罗伯茨博士选择了飞机 Dr. Roberts takes to the air.
调查中 他发现了一条关键的证据 His investigation leads him to a crucial piece of evidence -
冰面上奇妙的碗状凹陷 this strange bowl-like depression on the surface of the ice.
这真是个美妙的地方 This is an amazing location.
冰面上巨大的凹陷是由于冰盖底层下 This giant depression in the--in the ice has been formed
有个水囊不停吸水而形成 as a pocket of water has drained from beneath the base of the icecap.
你在冰面上看到的 The beautiful concentric crevasses
美丽的中心凹陷 that you see on the ice surface
就是由于水被吸收 have formed as the ice has slowly crept into the hollow
冰缓慢地向凹陷处延伸形成的 that's been created as the water has drained away.
冰层下 正进行着激烈的运动 Beneath the ice, a dynamic process is happening.
在地下 炽热的岩浆和蒸气使冰川融化 Hot magma and steam are melting the glacier from underneath.
融水在地下火山的顶部 The meltwater collects in a huge ice basin,
汇集成一个巨大的冰盆 at the top of the volcano.
随着冰盆慢慢被融水填满 The basin slowly fills, but as it does,
它周围的冰层开始变得不稳定 the surrounding ice becomes unstable.
冰盆开始出现裂痕 Cracks appear in the ice basin and,
那些热水从裂缝流走 形成了 一条 as the hot water drains away, it forms a tunnel
通向冰川边缘的通道 which channels the water to the edge of the glacier.
这说明 即使在质量庞大的冰川下 This would suggest that volcanic eruptions still happen,
火山仍在喷发 even under the enormous weight of ice.
这个过程会是解释古代大洪灾的关键吗 Is this process the key to explaining the ancient cataclysmic flood?
要想得到答案 To answer this
我们必须前往冰岛最大的火山之一 we must go to one of Iceland's largest volcanoes,
格里姆火山 Grimsvotn.
这座巨大的火山 Lying entombed beneath the ice
潜伏在瓦特那冰川的中心冰带下 in the heart of Vatnajokull,
每十年就会剧烈喷发一次 this massive volcano violently erupts every ten years.
在这里 冰火交融 惊天动地 Here, fire and ice spectacularly collide,
冰岛的火山占据了这场战役的优势 with Iceland's volcanoes emerging victorious.
冰川无法压制住火山无与伦比的威力 Ice cannot suppress the invincible power of Iceland's volcanoes,
却找到一条新的途径 发泄它们的愤怒 which have now found a new way to vent their anger.
在一次如此大规模的喷发中 During a huge eruption like this,
格里姆火山融化的冰足以填满 Grimsvotn can melt enough ice to fill
美国最大的人工湖 密德湖 America's largest man-made reservoir, Lake Mead.
但冰川无法长时间承受 But this vast volume of water
如此之多的融水 cannot be held back by the ice for long
因此 冰川融化 and leads inevitably
不可避免地引发了一场大洪水 to a massive glacial flood.
1996年 这股自然之力袭击了冰岛 Such a force of nature struck Iceland in 1996,
造成了毁灭性的打击 with devastating consequences,
洪水所到之处 所剩无几 the floodwater taking out everything in its path.
洪水冲断了桥梁 冲走了断桥残骸 Bridges were torn down and swept away,
高速公路也被大水淹没 and the highway was submerged under water.
洪水的洪峰流量 The flood itself reached a--a peak discharge of
超过了每秒一百八十万立方英尺 over 1.8 million cubic feet per second,
这是个令人惊叹的流量 that's a remarkable discharge,
相当于亚马逊河的夏季流量 equivalent to the summertime discharge of the River Amazon.
想象一下 一个相对小的区域 Imagine that sort of condition
却有如此惊人的流量 over a relatively small area.
洪水的力量带动了冰山 The sheer force of the water carried icebergs
它们有四层楼那么高 the size of four-storey buildings.
像这样的洪水 It's floods like these
在数日之内 便可颠覆一切 that can change the landscape in a matter of days.
洪水的这种侵蚀能力 The erosive power of the flowing water
能够侵蚀无数的石块 can result in tremendous amounts of--of rock being eroded,
实际上 它们会被洪水产生的高水压 literally being fractured away by the high water pressure
冲成碎片 that's being created.
不夸张的说 一场凶猛的洪水过后 So, literally, a landscape can form
你的眼前就会出现与之前截然不同的景象 before your eyes during a very severe glacial flood.
关于冰岛奇异地貌的推测已初具雏形 The story of Iceland's bizarre landscape is taking shape.
石头上的擦痕展现了冰川强大的力量 Striations on rock prove that ice is a formidable force
这股力量切割出冰岛独特的海岸线 that carved out Iceland's unique coastline.
散布在空旷山谷中的巨石 Boulders strewn in an empty valley
揭示了一场古老的洪灾 reveal cataclysmic floods of the past.
而冰层上的凹陷证实了 And depressions in the ice confirm that
冰岛火山无法抑制的威力 Iceland's volcanoes could not be suppressed.
但一万两千年之前 茫茫冰盖开始消融 But 12,000 years ago, the great ice sheets retreated,
冰岛逃离了严寒的禁锢 and Iceland was liberated from their wintry grip.
现在 冰岛的火山 Now, the effects of Iceland's volcanoes
正影响着整个地球 would be felt on a global scale.
有那么几千年的时间 For thousands of years,
冰岛上的火山与冰川僵持在一场恶战之中 Iceland's volcanoes were locked in a titanic battle with ice,
然而 一万两千年之前 but then, 12,000 years ago,
庞大的冰盖最终消融 the giant ice sheets finally retreated.
这开启了冰岛火山史的新篇章 This would open a new chapter in Iceland's volcanic history,
它们可以尽情肆虐了 as they were now free to wreak havoc.
但这会给冰岛及其周边带来什么影响呢 But what effect would this have on Iceland and its surroundings?
最引人注目的影响之一 One of the most dramatic effects can be found
拉基火山
位于岛上的中南地区 in the south central region of the island.
这里奇异的地貌叫做拉基火山 This alien landscape is known as Laki.
奇形怪状的火山坑排成一行 A row of strange craters and solidified lava flows
从地面大裂缝中冒出的熔岩在这凝固 that have bubbled up from a huge tear in the earth.
一次大规模的裂缝喷发 A massive fissure eruption,
在这片地貌上 it stretches for an astounding 16 miles
令人惊异地延伸了十六英里 across the landscape.
火山学家托尔·索达生博士 Volcanologist Dr. Thor Thordarson
正在对拉基火山进行研究 is investigating Laki,
这里发生过近代历史上 the site of one of the greatest eruptions
最为宏伟的火山喷发之一 in recent history,
也对世界造成了毁灭性的影响 one which would have devastating effects worldwide.
拉基火山裂缝从西南这里开始延伸 The Laki fissures which extend from here in the southwest
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托尔·索达生博士
爱丁堡大学
穿过这片地貌 形成一排火山锥 continue here through the landscape as a row of cones,
在这 它穿过拉基火山 up here, through Mount Laki,
拉基火山在喷发中被一分为二 which was split into two during the eruption,
继续向远处延伸到东北方向 and continue further to the northeast
一直延伸到冰川的边缘地区 all the way to the margins of the glaciers here.
目击记录精确表明喷发发生于一七八三年 Eyewitness accounts accurately date the eruption to 1783.
这是冰岛历史上最惨痛的几年之一 This was one of the most disastrous years in Icelandic history.
火山喷发物导致庄稼颗粒无收 Fallout from the eruption caused harvests all over the island to fail
百分之七十五的家畜死亡 and 75 percent of the livestock died,
随后冰岛陷入了一场大饥荒 plunging Iceland into a great famine
一万人因此丧命 which killed ten thousand people.
难以理解的是 在同一时期 But mysteriously, at the same time,
北半球的其它地区却出现极其寒冷的天气 the rest of the northern hemisphere reported freakishly cold weather.
比正常气温平均低二点三华氏摄氏度 Averaging 2.3 degrees Fahrenheit below normal,
北半球一片冰天雪地 the northern hemisphere froze over.
荷兰海岸线沿北海全结了冰 The North Sea along the coast of Holland froze,
沿岸村庄的人们在冰面上往来 so people skated between villages along the coast.
那个冬天 密西西比的河水 There was ice on the Mississippi
一直冻到了新奥尔良 down by New Orleans in that winter.
多年以来 人们都认为拉基火山的喷发 For many years, it was thought the Laki eruption
与这些气候变化没有关系 and these climatic events were unrelated,
但随着地质学的发展 but advances in geology found
人们发现这不仅仅是离奇的巧合 it wasn't just a bizarre coincidence.
对比目击记录和地质遗迹后 Comparing eyewitness accounts with the geological remains,
索达生博士再现了历史 Dr. Thordarson has reconstructed what happened.
他发现 喷发始于 He discovered that the eruption started
一七八三年六月八日清晨的一次爆炸 with a bang on the morning of June 8th 1783.
被抛起的石块在空中飞舞 It sent rocks flying high into the air
大地被撕扯出一条一英里长的裂痕 and ripped the earth open along a one-mile tear.
然而 这仅仅是一个序幕 But this was just the beginning.
三天后 第二波喷发呼啸而来 Three days later, a second eruption ripped open,
然后是 第三波 第四波 第五波 then a third, fourth, fifth.
地壳上总共撕扯出十道大裂痕 In total, the earth unzipped along ten vast tears in the crust,
岩浆不断喷涌而出 持续了八个多月 erupting lava continuously, for over eight months.
从地底倾泻而出的岩浆规模极其庞大 The mammoth amounts of lava that poured out of the ground here
足以使曼哈顿淹没在 would have buried Manhattan
八百三十英尺深的岩浆之下 to a depth of 830 feet.
但这个如此偏远小岛的一次喷发 But how an eruption on this small, remote island
是如何引起千里之外的气候紊乱的呢 could cause climatic chaos thousands of miles away
这仍是个谜 remained a mystery.
能解释拉基火山 The evidence that would link Laki
与世界气候灾难之间联系的证据 with this worldwide catastrophe
就藏在这些巨石之中 was locked inside these boulders.
故事就写在这些岩石中 The story is in the rocks.
这块岩石是在喷发过程中 This rock here is part of the material,
带出的岩浆物质 the magma that came out during the eruption.
这些洞叫做气泡 These holes are called bubbles.
它们是在地下的岩浆 And they form as the magma rises from deep within the ground
涌至表面 and approaches the surface,
开始沸腾的时候形成的 and it really starts to boil.
在地球深处时溶解在岩浆中的气体 The gas which is dissolved in the magma at depth
变成气泡 goes into the bubbles,
然后逃逸到大气之中 then it escapes into the atmosphere.
当这种"气泡岩石"喷发到地表时 When this "bubble rock" erupted onto the surface,
会将大量气体注入冰岛的大气层 it would have poured gas out into the Icelandic atmosphere.
是这种气体导致了全球性的气候紊乱吗 Could this gas have caused climatic chaos across the globe?
这种气体的成分 The identity of this gas can be found
可以由岩石在显微镜下的构造得出 in the microscopic structure of the rock.
如果你仔细观察这块岩石 If you look closely at this rock,
你可以看到很多的白色微粒 you can see a lot of white specks.
这些白色微粒是生长于 These little white specks are crystals
地球深处岩浆中的晶体 who grow in the magma at depth.
有时 在晶体生长过程中 Sometimes these crystals, as they grow,
它们会将原始岩浆包裹起来 they will encapsulate pristine magma
带到地球表面 and bring it up to the surface.
像密封容器一样 Like time capsules,
这些白色晶体包含着来自一七八三年 the white crystals contain untouched magma from deep in the Earth,
地球深处未受损的岩浆 locked away since 1783.
索达生博士分析了这些岩浆 Dr. Thordarson has analyzed this magma
发现它含有有毒的二氧化硫 and found it to contain poisonous sulphur dioxide.
由于这里有这么多熔岩 And because there was so much lava here,
所以 当时肯定释放了大量的有毒气体 it would have released enormous amounts.
令人震惊的一亿吨二氧化硫气体 A staggering 100 million tons of sulphur dioxide gas
被释放到大气中 was pumped into the atmosphere.
但是 拉基火山释放的气体 But how could gases released from Laki
是如何造成全球气候变冷的呢 cause bitterly cold weather across the globe?
问题的答案就在一七八三年六月 The answer lay in accounts of a thick red fog
对冰岛上空红色浓雾的记录中 reported over Iceland in June 1783.
几周之内 它们已经被吹到 Within a few weeks, it had been blown
伦敦和巴黎的上空 over London and Paris,
截止七月 它已经遍布整个北半球 and by July it had dispersed across the entire northern hemisphere.
科学家们现在知道 红色浓雾是由 Scientists now know that the red fog was caused
涌入空中的二氧化硫造成的 by the sulphur dioxide which rose high into the air.
与水混合后 它形成了硫酸烟雾 Mixing with water, it created a sulphuric acid haze.
烟雾挡住了太阳 导致气温骤然下降 The haze blocked out the sun and it sent temperatures plummeting.
结果 北半球 As a result, the northern hemisphere
历经三个严冬 endured three bitterly cold winters,
并导致春洪 饥荒 which brought spring floods, famine
欧洲遍地贫困 and widespread poverty to Europe.
一些历史学家一直相信 Some historians have long believed that
正是这些气候条件引起了社会及政治动荡 these climatic conditions triggered social and political unrest
最终导致一七八九年法国大革命的爆发 which led to the French Revolution in 1789.
但是科学家现在怀疑 But scientists now suspect
拉基火山的影响远非如此 Laki had ramifications even further afield.
北部的低温 The cold temperatures in the north
改变了南部的气流 changed air currents in the south,
导致了巨大的气候变化 causing dramatic climate changes.
印度遭遇严重的旱灾 India was hit by a terrible drought.
据说 五十多万人 People say that more than half a million people died
死于印度旱灾 from the drought in India.
并且 这一大气循环的改变 Also, this change in atmospheric circulation
使日本经历了一个寒冷的夏天 caused a very cold summer in Japan.
天气又冷又湿 水稻歉收 It was cold and wet, the rice harvest failed
结果便是日本历史上最严重的饥荒 and the result was the greatest famine in Japanese history.
据估计 在世界范围内 It is estimated that
拉基火山导致了两百多万人死亡 Laki killed over two million people worldwide
是人类历史上 最具破坏性的 and was one of the most devastating volcanic eruptions
火山爆发之一 in the history of mankind.
冰岛近期的火山爆发 The evidence has proven that
已经证明 Iceland's recent volcanic history
其对岛屿本身及其他地方 has had a devastating effect on the island,
有毁灭性影响 and the rest of the world.
庞大的火山岩表明 Enormous lava fields reveal
拉基火山是一次巨大的火山喷发 that Laki was a gigantic eruption.
岩石中的气泡表明 Bubbles in the rock indicate
拉基火山爆发 释放了大量的气体 that huge volumes of gas were released from Laki.
白色晶体表明 The white crystals reveal that
这种气体是有毒的二氧化硫 this gas was poisonous sulphur dioxide.
这些都是冰岛火山 Evidence that Iceland's volcanoes
导致全球气候紊乱的证据 caused climatic mayhem across the globe.
但诸如拉基火山这样的火山爆发 But eruptions like Laki
并非只限于过去 may not be confined to the past.
有人认为 冰与火间的平衡正在转换 Some believe that the balance between fire and ice is shifting
这可能导致冰岛 and has the potential to propel Iceland
再次成为人间地狱 into another hell on Earth.
大量证据表明 The evidence is mounting that
冰岛有可能成为这个星球上最致命的岛屿 Iceland has the potential to be the most lethal island on the planet.
一股可怕的火山力量藏匿其下 A fearsome volcanic force lies beneath it,
正在制造能够产生庞大熔岩流 creating powerful volcanoes capable of
改变全球气候的强大火山 generating gigantic lava flows and altering global climates.
冰岛的许多火山目前还覆盖在冰层之下 Yet many of Iceland's volcanoes are covered in glaciers.
冰与火处于一种微妙的平衡状态 Fire and ice are held in a delicate balance.
科学家们担心 如果这一平衡 Scientists fear if this balance were tipped
向火山的一方倾斜 in the volcanoes' favor,
冰岛将更为致命 Iceland could become even deadlier.
如果剩余的冰融化 If the remaining ice were to melt,
将会对冰岛的火山活动产生怎样的影响呢 what effect would it have on the activity of Iceland's volcanoes?
这一调查的首要线索 The first clue in the investigation lies
藏在成堆的岩石瓦砾中 in these innocuous looking piles of rock and rubble.
它们遍布冰岛 They're found all over Iceland,
但是这些岩石并非产生于火山爆发 and yet these rocks don't come from a volcano.
它们是冰碛 They're moraines,
冰川口沉淀的岩石堆的地质学名称 the geological term for rock piles deposited at the mouth of a glacier.
这些沉淀物是冰川正在消融的证据 These deposits are evidence that the glaciers are shrinking.
年复一年 冰川不断融化 Year by year, the glacier has melted
后退至山谷 and retreated back up the valley,
身后留下这样的冰碛 leaving a moraine like this behind.
过去十年 罗伯茨博士通过研究 Dr. Roberts has studied the Vatnajokull glacier
瓦特纳冰川 注意到这一显著趋势 for the last ten years and has noticed this dramatic trend.
冰川以惊人的速度撤退 The glacier has retreated at a remarkable rate.
马修·罗伯茨博士 冰岛气象局
我时常探访这一区域 Since I've been visiting the area,
我见证了巨大的变化 I've seen tremendous changes.
冰川大约以每年200英尺的速度撤退 The ice has retreated annually at a rate of about 200 feet per year.
这个湖过去曾被冰川所覆盖 This lake over here used to be filled with ice.
我看到冰川日益融化 I've seen the ice progressively melt,
冰碛形成 this moraine has formed
整个山谷几乎完全裸露出来 and this whole valley has become almost bare.
也许未来二十年内 Maybe in the next 20 years,
整个冰川都会消失 this whole glacier will disappear
山谷中会形成一个湖泊 and a lake will form in the valley.
冰岛的冰川正以史无前例的速度消融 Iceland's glaciers are melting at an unprecedented rate.
过去四十年中 冰岛百分之五的冰盖 With five percent of Iceland's icecaps melting
已经融化 in the last 40 years,
科学家们急于了解的问题是 the question that scientists are keen to understand is
这种迅速的融化 what effect this rapid melting
会对其下的火山产生怎样的影响 will have on the volcanoes that lie beneath.
上一次冰川如此迅速融化 The only other time that glaciers have melted this quickly
是在上个冰河时代 冰岛刚刚出现时 is when Iceland came out of the last Ice Age.
但是 过去的事件能给未来什么启示呢 But what can past events tell us about the future?
地质学家比尔·麦克奎教授在研究 Geologist Professor Bill McGuire is investigating
上个冰河时代末期 how volcanic activity changed
火山运动是如何改变的 at the end of the last Ice Age,
他发现了一些惊人的结果 and he's unearthed some surprising results.
大约在一万一千或者一万两千年前 Around about 11 or 12,000 years ago,
■
伦敦大学
比尔·麦克奎教授
冰岛及其他地方开始出现 you--you started to see quite rapid melting of glaciers
快速的冰川融化 in Iceland and elsewhere,
这导致火山活动显著增多 and that triggered a--a recognizable increase in volcanic activity
因为大量的冰迅速消失 because you were removing this large mass of ice very, very quickly.
迅速的消融惊醒了下面的火山爆发 The rapid melting of ice kick-starts volcanic eruptions beneath.
火山爆发是由岩浆中的气体引发 Volcanic eruptions are triggered by the gas in the magma,
这些气体产生气泡 which expands to form bubbles,
气泡驱动了火山爆发 and the bubbles drive the eruption.
这就像取出了一瓶香槟的软木塞 It's rather like taking the cork out of a--a bottle of champagne.
如果火山上有巨大的压力 Now, if you have a very heavy weight on top of a--a volcano,
如果存在大量的水或者冰 if there's a heavy mass of water or ice,
那会帮助压制爆发活动 that can help suppress eruptive activity.
但是当冰川快速融化 But when ice melts quickly,
这一向下的压力瞬间消失 this downward pressure is suddenly released,
这就成为危机的起源 and that's when the trouble starts.
随着冰川的融化 As the ice melts,
地下岩浆减少了 so the pressure on the magma underneath is reduced,
岩浆中的气泡可以传化成气泡 the gas in the magma can form bubbles,
它们可以联合 最终促使岩浆 they can coalesce and they can eventually drive the magma
向上涌出地面 upwards towards the surface
并引起爆炸性的喷发 and trigger either explosive eruptions or effusions of lava
使熔岩喷出很远 that can spread out over huge distances.
冰岛的冰川正在迅速消融 Iceland's glaciers are melting rapidly.
这使科学家们相信 This has led scientists to believe that
一场与拉基火山同等规模的毁灭性喷发 a devastating eruption on the scale of Laki
还会再次爆发 could happen again.
只是时间问题 The question is when.
我们需要对其有所思考 These are things that we have to think about
并且提前做好准备 and try to prepare ourselves to deal with
以免它们发生在我们有生之年 if they happen in our lifetime.
冰岛可能会再次发生一次这样的喷发吗 Is it possible that we can get another eruption like this in Iceland?
肯定会 Definitely.
调查已经揭示出 The investigation has revealed
冰岛这座广阔而不安的岛屿形成的过程 how the vast and violent island of Iceland was formed.
辛维里尔平原上的裂缝 Cracks in the Thingvillir Plain
和岩石中的化学成分 and traces of chemicals in the rocks
揭示了中大西洋海岭与热点 revealed how the Mid-Atlantic Ridge and hotspot
一同创造出了一个柱状的火山力量 joined forces to create a colossal volcanic force.
大量的裂缝喷发将陆地撕裂 Massive fissure eruptions ripped the land open.
喷出成千上万吨熔岩 冰岛迅速形成 Hemorrhaging millions of tons of lava, Iceland rapidly formed.
北部峡湾有力地证明了 Deep northern fjords were evidence that
巨大的冰层侵蚀了陆地 埋葬了火山 a giant ice sheet eroded the land and entombed the volcanoes,
将火与冰的剧烈战斗镇压 locking fire and ice in a titanic battle.
散落在古老山谷中的巨石 Boulders, strewn in an ancient valley,
揭示了火如何胜利 revealed how fire emerged victorious,
释放洪水 unleashing cataclysmic floods.
岩石中的微粒显示 And specks of sulphur in the rocks showed
冰岛火山有可能 how Iceland's volcanoes have the potential
造成全球性破坏 to cause global destruction.
现在 一些世上最为危险的 Now glaciers, melting above some of the world's
火山上的冰川正在融化 most deadly volcanoes,
未来的爆发威胁不断增大 are increasing the threat of future eruptions.
在过去的两千万年间 Over the last 20 million years,
冰岛强大的火山力量创造了一个巨大的 Iceland's almighty volcanic force has created a vast,
奇异之地 alien landscape.
无法预言 Volatile and unpredictable,
也许某一天 它会再次大规模爆发 it may one day unleash a massive eruption
摧毁整个冰岛 which could devastate both Iceland
以及更为广阔的世界 and the wider world beyond.