英语大破解
How deep into the Earth have we gone? 人类抵达过地球内部多深的地方？
本集内容
How deep into the Earth have we gone?
人类抵达过地球内部多深的地方？
文字稿
What's the deepest into the Earth a human has ever been?
人类曾抵达过地球内部多深的地方？
The answer is only a tiny fraction.
答案是：只进入了极小的一部分。
The outer layer of the Earth is up to 70 kilometres deep in places.
地壳在一些地方厚达 70 公里。
But the deepest a human has ever been is just 4km.
但人类曾抵达过的最深处仅约 4 公里。
That's at a mine in South Africa.
那是在南非的一座矿井中。
We've also tried drilling boreholes, but the deepest one only got about 12km down – just a third of the way through the crust at that point.
人类还尝试过钻探深井，但最深的钻孔也只达到约 12 公里，仅相当于当地地壳厚度的三分之一。
Getting any further is really hard because of the vast pressures and really high temperatures the deeper you go.
想要再往下钻探就变得极其困难，因为越往深处，压力越大、温度越高。
But we can use seismometers to model the layers of the Earth.
不过，我们可以用地震仪来研究地球内部的分层结构。
Seismic waves travel through different materials differently, giving us an idea of what's there even if we can't see it for ourselves.
地震波在不同物质中的传播方式不同，这让我们知道地下深处有什么，即使无法亲眼看到。
This helps us answer questions like why volcanoes erupt, or why earthquakes happen.
这些知识能帮助我们解释一些问题，比如火山为什么会喷发，以及地震为什么会发生。
It can also show us how the Earth has evolved over time, which could help us learn about other planets, too.
它还能让我们了解地球的演变过程，这可能有助于我们研究其他行星。
重点词汇或表达
tiny fraction 极小的一部分
borehole 钻孔
crust 地壳
seismometer 地震仪
model 建立…的模型