Geologic Time Periods托福听力原文翻译及问题答案

2023-06-23 12:32:44 来源：中国教育在线

Geologic Time Periods托福听力原文翻译及问题答案

一、Geologic Time Periods托福听力原文：

Narrator:Listen to part of a lecture in a geology class.MALE PROFESSOR:As geologists,we examine layers of sediment on the Earth's surface to approximate the dates of past geologic time periods.Uh,sediment,as you know,is material like sand,gravel⋯fossil fragments⋯that is transported by natural processes,like wind,water flow,or the movement of glaciers.So,uh,sediment is transported,and then deposited,and it forms layers on the Earth's surface over time.We examine these layers to learn about different geologic time periods,including when they began and ended.Uh,for example,from about 1.8 million years ago to around 11,000 years ago was the Pleistocene epoch.The Pleistocene epoch was an ice age.Uh,during this epoch,sediment was made by the kind of erosion and weathering that happens when the climate is colder.And part of those sediments are fossils of plants and animals that lived at that time.

The Holocene epoch followed the Pleistocene epoch when the Earth's climate warmed up around 11,000 years ago.The Holocene epoch is characterized by different sediments⋯ones that form when the climate is warmer.Because the climate changed,the types of plants and animals changed also.Holocene sediments contain remnants of more recent plants and animals.So it’s pretty easy to differentiate,geologically,between these two epochs.Now there’s growing evidence that the presence of humans has altered the Earth so much that a new epoch of geologic history has begun⋯the Anthropocene epoch,a new,human-influenced epoch.This idea,that we've entered a new,Anthropocene epoch,was first proposed in 2002.The idea is that around the year eighteen hundred C.E.,the human population became large enough,around a billion people,that its activities started altering the environment.

This was also the time of the Industrial Revolution,which brought a tremendous increase in the use of fossil fuels,such as coal.The exploitation of fossil fuels has brought planetwide developments—industrialization,construction,uh,mass transport.And these developments have caused major changes,like additional erosion of the Earth's surface and deforestation.

Also,things like the damming of rivers has caused increased sediment production.Not to mention uh,the addition of more carbon dioxide and methane in the atmosphere.Naturally,all these changes show up in recent sediments.And these sediments are quite different from pre-year eighteen hundred sediment layers.

Interestingly,there's some speculation that humans started having a major impact on Earth much earlier,about 8,000 years ago.That's when agriculture was becoming widespread.Early farmers started clearing forests,and livestock produced a lot of extra methane.But I want to stress that this is just a hypothesis.The idea that early humans could’ve had such a major effect,well⋯I'm just not sure we can compare it with the Industrial Age.Geologists in the far future will be able to examine the sediment being laid down today.Whereas right now we can say that yes,human impact on the Earth is clear,it'll be future researchers who'll have a better perspective and will be able to really draw a line between the Holocene and the Anthropocene epochs.

二、Geologic Time Periods托福听力中文翻译：

旁白：听地质学课上的一节课。男教授：作为地质学家，我们研究地球表面的沉积物层，以接近过去地质时期的日期。呃，沉淀物，如你们所知，是像沙子、砾石这样的物质⋯化石碎片⋯这是通过自然过程运输的，如风、水流或冰川运动。所以，呃，沉积物被运输，然后沉积，随着时间的推移，它在地球表面形成了一层。我们检查这些地层以了解不同的地质时期，包括它们的开始和结束时间。例如，从大约180万年前到大约11000年前是更新世。更新世是冰河期。呃，在这个时期，沉积物是由气候较冷时发生的侵蚀和风化作用形成的。这些沉积物中的一部分是当时的动植物化石。

更新世之后是全新世，大约11000年前地球气候变暖。全新世具有不同沉积物的特征⋯当气候变暖时形成的。由于气候变化，动植物的种类也发生了变化。全新世沉积物中含有较新动植物的遗迹。所以从地质学上讲，很容易区分这两个时代。现在有越来越多的证据表明，人类的存在对地球的影响如此之大，一个新的地质历史时代已经开始⋯人类世，一个新的、受人类影响的时代。这个想法，即我们已经进入了一个新的人类世，是在2002年首次提出的。这个想法是在公元前1800年左右，人类人口变得足够大，大约有10亿人，其活动开始改变环境。

这也是工业革命的时期，工业革命带来了煤炭等化石燃料的大量使用。化石燃料的开发带来了工业化、建筑业、呃，大众运输业的全面发展。这些发展导致了重大变化，如地球表面的进一步侵蚀和森林砍伐。

此外，河流筑坝等事件也导致了泥沙产量的增加。更不用说大气中增加了更多的二氧化碳和甲烷。自然，所有这些变化都出现在最近的沉积物中。这些沉积物与前一年的1800个沉积层有很大不同。

有趣的是，有人猜测人类在8000年前就开始对地球产生重大影响。那是农业开始普及的时候。早期农民开始砍伐森林，牲畜产生了大量额外的甲烷。但我想强调的是，这只是一个假设。早期人类可能会产生如此重大的影响⋯我只是不确定我们能不能把它与工业时代相比。在遥远的将来，地质学家将能够检查今天沉积的沉积物。然而现在我们可以说，是的，人类对地球的影响是显而易见的，未来的研究人员将有更好的视角，能够真正在全新世和人类世之间划清界限。

三、Geologic Time Periods托福听力问题：

Q1:1.What is the lecture mainly about?

A.Recognizing when one geologic epoch ends and another begins

B.How geologists determine the age of Earth

C.Whether humans have affected Earth's climate

D.Identifying elements that affect the formation of sediment layers

Q2:2.Why does the professor mention the Pleistocene epoch?

A.To explain how sediments change during an ice age

B.To give an example of a well-defined geologic epoch

C.To describe how certain environmental conditions affect erosion rates

D.To describe the factors that influence the naming of geologic epochs

Q3:3.Researchers study sediment in order to learn about the characteristics of past geologic epochs.What does the professor say that sediment reveals about a particular epoch?[Click on 2 answers.]

A.The climate on Earth then the sediment formed

B.The places on Earth with the highest amounts of rainfall

C.The level of the oceans at the time

D.The organisms that lived when the sediment formed

Q4:4.According to the professor,what is the significance of the year 1800 C.E?[Click on 2 answers.]

A.The human population reached 1 billion.

B.The Anthropocene epoch was first described.

C.Industrialization began to influence Earth's environment.

D.There was a significant change in the amount of sediment deposited around the world.

Q5:5.What does the professor imply about the spread of agriculture 8,000 years ago?

A.It was the true beginning of the Holocene epoch.

B.It was when greenhouse gases were at their lowest levels.