纪录片《恐龙灭绝真相》 第15期 采集岩芯

At the end of 2001, an international team of scientists gathered near Chicxulub.

2001年底，一支国际科研小组来到希克苏鲁伯附近。

They used an oil rig to drill down over a kilometre into the heart of the crater¹.

他们利用石油钻探机钻入1公里深处的陨石坑中心。

They extracted hundreds of metres of rock cores,

他们采集了数百米深的岩芯，

most of the rock had been pulverised by the Chicxulub impact, but one section was undamaged.

大部分岩石都因为希克苏鲁伯大碰撞而变得粉碎，但是有一个截面却没有遭到破坏。

It lay above the broken rock, so it must have been created after the impact, and just underneath² the Iridium layer,

它位于破碎岩石之上，因此它肯定是在碰撞之后形成的，而且刚好是在铱元素层下方，

so the question was how long had this section taken to form?

现在的问题是，这个岩层花了多长时间形成？

If the mysterious rock had been formed slowly, it would support Keller and Wolfgang Stinnesbeck.

如果这些神秘的岩石形成缓慢，那也就证明了Keller和Wolfgang Stinnesbeck的理论。

What we can see here is the impact sediment³ which is all smashed off the rocks,

我们在这儿看到的是碰撞沉积岩，都是破碎不堪的岩石，

we see bigger pieces and smaller pieces here, but then we find something completely different.

有大块的，也有小块的，但是后来我们发现了一些很不一样的东西。

See this grey rock, this is a limestone⁴, and when I looked at the limestone with my head lens

例如这块灰色岩石，这是石灰岩，我用放大镜观察这块石灰岩时，

I noticed that the grains which are forming the limestone are very fine,

发现形成这些石灰岩的颗粒非常细小，

so that would show to me that this sediment has been deposited under rather quiet conditions.

因此在我看来，这些沉积岩肯定是在非常平静的条件下沉积形成的。

1 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。

2 underneath   

adj.在...下面，在...底下；adv.在下面

参考例句：

• Working underneath the car is always a messy job.在汽车底下工作是件脏活。
• She wore a coat with a dress underneath.她穿着一件大衣，里面套着一条连衣裙。

3 sediment   

n.沉淀，沉渣，沉积(物)

参考例句：

• The sediment settled and the water was clear.杂质沉淀后，水变清了。
• Sediment begins to choke the channel's opening.沉积物开始淤塞河道口。

4 limestone   

n.石灰石

参考例句：

• Limestone is often used in building construction.石灰岩常用于建筑。
• Cement is made from limestone.水泥是由石灰石制成的。