Narrator: Listen to part of a lecture in a geology class.

旁白：下面请听一段地质学课上的讲座。

Professor: Hi, class, let’s get started.

教授：嗨，同学们，我们开始上课啦。

Um, last time we finished up the section of coal, so we have just two fossil fuels left to talk about.

嗯，上节课我们讲完了煤炭部分，所以我们就只剩下两种化石燃料需要讲了。

Those are petroleum and natural gas.

也就是石油和天然气。

Today I will concentrate on petroleum and we will get into natural gas tomorrow.

今天我主要是集中讲石油，我们明天会开始讲天然气。

Like coal and natural gas, petroleum has been formed over millions of years, from remains of prehistoric plants and animals.

就像是煤炭和天然气一样，石油也是几百万年前就形成了，它是由史前的动植物的遗体形成的。

And like coal and natural gas, it’s found in the rocks of Earth’s crusts.

就像是煤炭和天然气一样，石油是在地壳岩层中被发现的。

In fact, the word "petroleum " literally means "rock oil".

实际上，“石油”这个词字面意义上指的就是“岩层里的油”。

And in its’ original state, the way we find it in Earth’s crust, it is called crude oil, sometime people will short that up, and just refer to it as crude.

石油原始的状态，及我们从地壳中发现它时的状态，是叫做原始状态的石油，有的时候人们会简化这个名字，就简单地叫它原油。

Um, petroleum also contains natural gas, so usually the petroleum industry is naturally searching for and utilizing deposits of both crude oil and natural gas at the same time.

嗯，石油也同样含有天然气，所以通常来说石油工业就是同时在寻找和使用原油加天然气的矿藏。

In other words, companies might as well gather, use and sell both the oil and the gas when they find it, since both are valuable.

换句话说，这些负责开采的公司在找到石油和天然气的时候会同时收集、使用和售卖两者，因为这两者同样有价值。

And...

还有……

Student: But what kind of organic materials, I mean, specifically what kind of dead plant and animals make up petroleum exactly?

学生：但是哪一种有机物质，我的意思是，具体是哪种死掉的动植物才可以形成石油呢？

Do you mean like trees and dinosaurs?

你的意思是树木和恐龙吗？

Professor: Well, apparently petroleum is usually made from simple, one-celled marine animals and plants, algae, for example.

教授：嗯，显然石油通常是来自于简单的单细胞海洋动植物，比如说藻类。

Um, what happens is this accumulated plant and animal material that originally came from the ocean gets covered by sediment.

嗯，会发生的事情是，这种来自海洋的不断积累的动植物尸体会被沉积物覆盖。

And then is... um, eventually exposed to earth internal heat and pressure, for millions of years.

然后……嗯，最终会暴露在地球内部的高热和高压下，这个过程可以有几百万年。

And over those millions of years, the heat cooks and the pressure molds that material, turning it into a thick, sticky liquid.

在这几百万年间，热量改变这些动植物尸体的性质，压力则为它们塑形，最终把它们变成了厚重粘稠的液体。

And since petroleum is made from these ocean organisms, you can guess where it was found, it makes sense that we usually find it under the ocean or near shore, right?

因为石油是来自于这些海洋生物的，你们可以猜一下哪里可以找到石油，我们经常在海底或者海岸边发现石油就显得很有道理了，对吗？

Yes, Ann?

安？

Ann: I’ve heard people talk of... ah... live and dead oils?

安：我听说有人会谈论……啊……活的石油和死的石油？

Professor: Well, um, when crude oil has a lot of natural gas mixed up with it, it’s called live oil.

教授：嗯，当石油里混有大量的天然气，这就叫做活的石油。

But if the gas escapes from the mixture, then oil is said to be dead.

但是如果天然气从石油里逃逸出来，那么这就被称为死的石油。

And it’s heavy and more difficult to pump.

死的石油很重，而且更难被泵出来。

Does anyone know how the gas separates from the oil?

有人知道天然气怎么从石油里逃逸出来吗？

Sam, go ahead.

山姆，你说。

Sam: Doesn’t it happen when the oil shoots up to the surface?

山姆：这是不是在石油被泵出来的时候发生的？

Professor: Yes, that’s right.

教授：是的，正确。

When oil reaches the surface of the Earth, there is less pressure on it.

当石油到达地面的时候，它所承受的压力就会变小。

And with less pressure, the oil and gas were able to separate.

在更小的压力下，石油和天然气就会分离。

The other way the crude oil was able to come up to the surface is by people pumping it up out of the ground.

另一种把石油带到地面的办法是人们人为地泵出它。

And, um, it’s the same thing that happens at the surface, there is less pressure, and, so the oil and gas separate.

而且，嗯，以这种方式泵出的石油和前一种情况一样，到达地面的时候也会承受较小的压力，所以，石油和天然气就分开了。

But when we talked about how it actually exists inside earth’s crust, most people think that there are huge, pools of oil sitting around in caverns somewhere under there.

但是当我们谈论到在地壳里面存在的到底是什么东西的时候，大多数人认为是巨大的一洼一洼的存在于洞穴里面的石油。

That’s really rare.

但其实这种情况是很稀少的。

The majority of petroleum is just filling in the tiny pores and cracks in rocks.

大多数石油仅仅就是填充在岩石里小的孔洞和裂缝中的。

Now, um, a little more on the petroleum industry.

现在，嗯，我们再多讲一点关于石油工业的东西。

As far as the extraction process the petroleum industry digs deep wells to reach underground oil fields where crude oil has accumulated over a large area and is trapped between layers of rocks.

石油提取的过程是石油工厂向地下钻很深的油井，以达到地下油田的位置，这些地下油田里的原油囤积在一大片区域里，渗透于层层岩石之间。

Then it pumps the crude oil out.

然后泵石油的机器会把原油泵出来。

Then its refineries have two main tasks, convert less valuable crude oil into a more valuable form and create usable products from refined oil.

然后精炼机器有了两个新任务，也就是把不怎么有价值的原油转化成更加有价值的形式，并且从精炼后的油里制造出可用的产品。

Basically, the refiner will do this by boiling the oil.

基本上，精炼机器会通过蒸馏来进行这个过程。

When the oil cools off, the stuff that is left is turned into a variety of products, like gasoline, diesel fuel for cars and trucks, asphalt for roads, um, paints, plastics, even soaps.

当石油冷却以后，它留下的东西可以被转化成各种各样的产品，就像是供给汽车和卡车的汽油，柴油，修路的沥青，嗯，颜料，塑料，甚至是肥皂。

And check what you’re wearing. If you are wearing something with synthetic fibers, what that really means is that it is made of the petroleum.

再看看你身上穿的衣服，如果你穿着含有合成纤维的衣服的话，这意味着它是由石油做成的。

So you can see petroleum is essential to today’s industrial society.

所以你们可以知道，石油对于现在的工业社会是多么至关重要。

Now, next week we will be joining the graduate students from the department of petroleum engineering to examine the comprehensive field study they’re working on in our local oil fields.

下周我们会和石油工程系的研究生一起去看看他们正在当地一处油田进行的综合性实地研究。

And I’d like you to read over the pack of information I’m about to hand out to you before we go.

我希望你们在出发之前读完我马上要给到你们的一些资料。

It should familiarize you with the history of the oil field we will be touring as well as the details of their project.

这些资料可以帮助你们熟悉这处我们将要去的油田的历史，还有这个项目的一些细节。