纪录片《恐龙灭绝真相》 第07期 寻找陨石坑

Alan Hildebrand who was based in Calgary in western Canada, was determined¹ to be the one to discover the crater².

Alan Hildebrand一直在加拿大西部的卡尔加里从事研究，他一心想找到这个陨石坑。

He knew the spherule layers should be thicker, the nearer he got to the crater itself...

他知道，越接近陨石坑，小球体层就应该越厚，

so he followed the trail of the spherules.

于是，他开始追寻小球体的踪迹。

Here in western Canada we have a layer at the Cretaceous-Tertiary boundary,

在加拿大西部的这个地方，我们找到了处于白垩纪的第三纪界线层，

it's about one centimetre thick on average.

它平均有1厘米厚。

In Colorado and New Mexico it's two or two and a half centimetres thick.

但在美国的科罗拉多和新墨西哥，它的厚度有2-2.5厘米。

Still further south in the Caribbean as in Haiti it's about a half metre thick

往南直到加勒比海的海底，厚度又达到了半米左右，

so by nineteen eighty nine we knew that the source crater had to be somewhere between North and South America.

所以在1989年，我们推测陨石坑一定就在北美洲和南美洲之间的某个地方。

Then Alan Hildebrand had a stroke of luck.

不久，Alan Hildebrand的好运来了。

He happened to be looking at an old oil company map,

他无意中看到了一幅石油公司的老地图，

he was looking at the Yucatan Peninsula in Mexico, near a village called Chicxulub, then he noticed something odd.

他在研究墨西哥的尤卡坦半岛时，在一个叫做希克苏鲁伯的小村庄附近他注意到了一些奇怪的东西。

This is when I spotted³: a horseshoe shape feature, we can see it better on this map.

我发现的就是这个：一个马蹄铁形的地貌，用这张地图可以更清楚地看到它。

The anomaly is a hundred and eighty kilometres across

这个特别的地方有180公里宽，

which was in the range of sizes predicted for this crater

这正好符合对陨石坑大小的推测，

and laying on the Yucatan Peninsula, between North and South America,

它位于尤卡坦半岛上，在南北美洲之间，

it's within the region where the ejecta thickness says the crater should lie.

这个地区的火山喷出物也表明了陨石坑的存在。

So this suggested that this might indeed be the crater that killed the dinosaurs⁴.

这些都说明它极有可能就是导致恐龙灭绝的那个陨石坑。

1 determined   

adj.坚定的；有决心的

参考例句：

• I have determined on going to Tibet after graduation.我已决定毕业后去西藏。
• He determined to view the rooms behind the office.他决定查看一下办公室后面的房间。

2 crater   

n.火山口，弹坑

参考例句：

• With a telescope you can see the huge crater of Ve-suvius.用望远镜你能看到巨大的维苏威火山口。
• They came to the lip of a dead crater.他们来到了一个死火山口。

3 spotted   

adj.有斑点的，斑纹的，弄污了的

参考例句：

• The milkman selected the spotted cows,from among a herd of two hundred.牛奶商从一群200头牛中选出有斑点的牛。
• Sam's shop stocks short spotted socks.山姆的商店屯积了有斑点的短袜。

4 dinosaurs   

n.恐龙( dinosaur的名词复数 )；守旧落伍的人，过时落后的东西

参考例句：

• The brontosaurus was one of the largest of all dinosaurs. 雷龙是所有恐龙中最大的一种。 来自《简明英汉词典》
• Dinosaurs have been extinct for millions of years. 恐龙绝种已有几百万年了。 来自《简明英汉词典》