ABOUT THE SPEAKER
Liz Hajek - Geoscientist
Liz Hajek studies sedimentary rocks to understand how landscapes change and evolve.

Why you should listen
Liz Hajek's research has contributed new perspectives on how rivers and coastlines move and how sediments record earth history. She is an assistant professor of geosciences at The Pennsylvania State University, where she teaches a range of courses spanning topics from oceanography to petroleum geology. Hajek and her students often conduct fieldwork in rugged places and use computer models and experiments to reveal the rhythms and dynamics of earth's surface. She recently appeared in the NOVA Treasures of the Earth: Power episode and has a paper in the Annual Review of Earth and Planetary Sciences.
More profile about the speaker
Liz Hajek | Speaker | TED.com
TEDxPSU

Liz Hajek: What rivers can tell us about the earth's history

Liz Hajek: 河流告诉我们的地球历史

Filmed:
1,376,299 views

河流是自然最强大的力量之一——它们推动高山,侵蚀大地,而且河道也一直在变化。理解它们如何形成以及如何变化对居住在河岸旁和三角洲的人来说十分重要。在这一图片信息丰富的演讲中,地质学家Liz Hajek向我们展示了由古代河流堆积成的岩石如何可以被用作时间机器来研究地球的历史,从而让我们得知在今天应当如何可持续的生存下去。
- Geoscientist
Liz Hajek studies sedimentary rocks to understand how landscapes change and evolve. Full bio

Double-click the English transcript below to play the video.

00:12
All right, let's get up
our picture图片 of the earth地球.
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好的,我们来看看地球的照片。
00:16
The earth地球 is pretty漂亮 awesome真棒.
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地球确实令人惊叹。
00:18
I'm a geologist地质学家, so I get
pretty漂亮 psyched激动 about this,
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我是名地质学家,所以对这很着迷,
地球很伟大。
00:20
but the earth地球 is great.
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00:21
It's powerful强大, it's dynamic动态,
it's constantly经常 changing改变.
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它充满力量,充满活力,
时时刻刻都在变化。
确实是个令人兴奋的居住地。
00:25
It's a pretty漂亮 exciting扣人心弦 place地点 to live生活.
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00:28
But I want to share分享 with you guys today今天
my perspective透视 as a geologist地质学家
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但我今天想从一个地质学家的视角
和你们分享,了解地球的过去
00:32
in how understanding理解 earth's地球 past过去
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00:34
can help inform通知 and guide指南
decisions决定 that we make today今天
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将如何帮助并指导我们在地球上
可持续的生存下去。
00:37
about how to sustainably可持续 live生活
on earth's地球 surface表面.
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00:41
So there's a lot of exciting扣人心弦 things
that go on on the surface表面 of the earth地球.
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地球表面有着许多令人兴奋的事物。
如果我们在这里放大一点,
00:45
If we zoom放大 in here a little bit,
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00:47
I want to talk to you guys a little bit
about one of the things that happens发生.
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我想和你们谈谈一个现象。
物质在地球的表面不断被冲刷,
00:51
Material材料 get shuffled洗牌 around
earth's地球 surface表面 all the time,
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其中一个重要的影响是,
高山上的东西也会被冲刷掉,
00:53
and one of the big thing that happens发生
is material材料 from high mountains
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被搬运并最终沉淀于海底。
00:57
gets得到 eroded侵蚀 and transported
and deposited沉积 in the sea.
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这一过程一直发生着,
00:59
And this process处理 is ongoing不断的 all the time,
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并且深刻的影响了地形的形成。
01:01
and it has huge巨大 effects效果
on how the landscape景观 works作品.
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举个例子,在印度南部
01:03
So this example here in south India印度 --
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01:05
we have some of the biggest最大
mountains in the world世界,
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有着世界上最高的山峰,
01:08
and you can see in this satellite卫星 photo照片
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你可以从这张卫星图像上看到,
01:10
rivers河流 transporting传输 material材料
from those mountains out to the sea.
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河流运输着这些山上的东西直至海洋。
你可以把这些河流想象成推土机。
01:14
You can think of these rivers河流
like bulldozers推土机.
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它们基本上就是在拽着这些山峰,
将它们向海的方向推移。
01:16
They're basically基本上 taking服用 these mountains
and pushing推动 them down towards the sea.
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01:21
We'll give you guys an example here.
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给你们举个例子。
01:23
So we zoom放大 in a little bit.
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我们放大一点。
我想和你们具体谈谈其中一条河。
01:24
I want to talk to you guys
specifically特别 about a river.
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我们可以看到河流
运输物质到海洋的过程中,
01:27
We can see these beautiful美丽 patterns模式
that the rivers河流 make
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描绘出的美丽图案,
01:29
as they're pushing推动 material材料
down to the sea,
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但是这些图案不是一成不变的。
01:32
but these patterns模式 aren't static静态的.
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这些河流这里绕一绕,那里绕一绕,
01:33
These rivers河流 are wiggling摆动
and jumping跳跃 around quite相当 a bit,
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就会对我们的生活产生很大的影响。
01:36
and it can have big impacts影响 on our lives生活.
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其中一个例子是戈西河。
01:38
So an example of this
is this is the Kosi科西 River.
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01:40
So the Kosi科西 River
has this nice不错 c-shapedC形 pathway,
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戈西河有着漂亮的C形河道,
01:43
and it exits退出 the big mountains of Nepal尼泊尔
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它从尼泊尔的高山流出,
带着成吨的矿物,
01:45
carrying携带 with it a ton of material材料,
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通过侵蚀高山得到的沉积物,
01:48
a lot of sediments沉积物 that's being存在
eroded侵蚀 from the high mountains,
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穿过印度,
01:51
and it spreads利差 out across横过 India印度
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并且运输着它们。
01:52
and moves移动 this material材料.
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01:54
So we're going to zoom放大 in to this area
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我们将放大这一块区域,
01:56
and I'm going to tell you a little bit
about what happened发生 with the Kosi科西.
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而我将告诉你们戈西河发生的事情。
这个例子告诉了我们
这些系统的动态程度。
02:00
It's an example of how dynamic动态
these systems系统 can be.
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这是2008年八月的一张卫星图像,
02:02
So this is a satellite卫星 image图片
from August八月 of 2008,
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已经被着色了,
02:06
and this satellite卫星 image图片 is colored有色
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所以植物或植被都是绿色的,
02:08
so that vegetations植被 or plants植物
show显示 up as green绿色
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水是蓝色的。
02:10
and water shows节目 up as blue蓝色.
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你可以看到当它离开尼泊尔时
02:12
So here again you can see
that c-shapedC形 pathway
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是呈C形的河道。
02:15
that this river takes as it exits退出 Nepal尼泊尔.
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02:18
And now this is monsoon雨季 season季节.
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现在是季风季节。
02:20
August八月 is monsoon雨季 season季节
in this region地区 of the world世界,
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八月是这个地区的季风季节,
任何住在河流旁边的人都对洪水
02:22
and anyone任何人 that lives生活 near a river
is no stranger陌生人 to flooding洪水
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以及洪水带来的危害
和不便不感到陌生。
02:25
and the hazards危害 and inconveniences不便之处
at minimum最低限度 that are associated相关 with that.
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02:29
But something interesting有趣
happened发生 in 2008,
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但是2008年发生了有趣的事情,
02:31
and this river moved移动 in a way
that's very different不同.
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这条河流以十分不同的方式变化了。
它以与平常不同的方式造成了洪水。
02:34
It flooded in a way that's very
different不同 than it normally一般 does.
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戈西河流到这里,
02:37
So the Kosi科西 River is flowing流动 down here,
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02:40
but sometimes有时 as these rivers河流
are bulldozing推土 sediment沉淀,
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但是有时随着这些河流
运输的沉积物越来越多,
河道开始堵塞了,
02:43
they kind of get clogged堵塞,
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而这些堵塞实际上可以
02:44
and these clogs木底鞋 can
actually其实 cause原因 the rivers河流
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导致河流走向的巨大变动。
02:46
to shift转移 their course课程 dramatically显着.
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这是仅仅两周后的卫星图像。
02:48
So this satellite卫星 image图片
is from just two weeks later后来.
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这是之前的河道,
02:51
Here's这里的 the previous以前 pathway,
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那C形的河道,
02:53
that c-shapedC形 pathway,
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你会发现它不再是蓝的了。
02:54
and you notice注意 it's not blue蓝色 anymore.
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现在蓝色的河道,
02:56
But now what we have is this blue蓝色 pathway
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在图中央纵切了一刀。
02:58
that cuts削减 down the middle中间
of the field领域 of view视图 here.
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现实中,戈西河漫上了它的河堤,
03:01
What happened发生 is
the Kosi科西 River jumped跳下 its banks银行,
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还有这里的比例尺是40英里。
03:03
and for reference参考,
the scale规模 bar酒吧 here is 40 miles英里.
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这条河十分突然的
移动了超过30英里。
03:06
This river moved移动
over 30 miles英里 very abruptly突然.
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03:10
So this river got clogged堵塞
and it jumped跳下 its banks银行.
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这条河堵住了,然后漫过了河堤。
03:13
Here's这里的 an image图片 from about a week later后来,
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这是一周后的一张图片,
你可以看到这些是之前的河道,
03:15
and you can see
these are the previous以前 pathways途径,
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而且漫堤的过程仍在继续,
03:18
and you can see this process处理
of river-jumping江跳 continues继续
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这条河离它的主道越来越远。
03:20
as this river moves移动 farther更远 away
from its major重大的 course课程.
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03:23
So you can imagine想像
in landscapes景观 like this,
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所以你可以想象,
03:26
where rivers河流 move移动 around frequently经常,
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在这种河流经常改道的地形里,
理解河流何时、何地以及
如何改道是十分重要的。
03:28
it's really important重要 to understand理解 when,
where and how they're going to jump.
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但是这种过程同样也发生在我们身边。
03:33
But these kinds of processes流程
also happen发生 a lot closer接近 to home as well.
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03:37
So in the United联合的 States状态,
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在美国,
03:39
we have the Mississippi密西西比州 River
that drains水渠 most of the continental大陆 US.
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密西西比河流经大部分的美洲大陆。
它推动着来自落基山脉
03:43
It pushes material材料
from the Rocky洛基 Mountains
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和大平原的物质。
03:45
and from the Great Plains平原.
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它夹带着这些物质贯穿美国,
03:47
It drains水渠 it and moves移动 it
all the way across横过 America美国
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然后把它们倒入墨西哥湾。
03:50
and dumps转储 it out in the Gulf海湾 of Mexico墨西哥.
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03:53
So this is the course课程 of the Mississippi密西西比州
that we're familiar with today今天,
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这是我们今天熟悉的密西西比河河道,
但是它并非一直是按这个方向流动的。
03:56
but it didn't always flow
in this direction方向.
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如果我们利用地质记录,
03:58
If we use the geologic地质 record记录,
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就可以重建它过去的走向。
04:00
we can reconstruct重建
where it went in the past过去.
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04:04
So for example, this red area here
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举个例子,这里红色的区域
04:06
is where we know the Mississippi密西西比州 River
flowed流入 and deposited沉积 material材料
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据我们目前所知,是大约
4600年前密西西比河流过
并且沉积物质的地方。
04:10
about 4,600 years年份 ago.
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04:12
Then about 3,500 years年份 ago it moved移动
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然后大约在3500年前,
04:14
to follow跟随 the course课程
outlined概述 here in orange橙子.
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它移动到了橘色标注的河道流动。
它一直移动,不停移动。
04:16
And it kept不停 moving移动 and it keeps保持 moving移动.
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04:18
So here's这里的 about 2,000 years年份 ago,
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这是约2000年前,
1000年前,
04:20
a thousand years年份 ago,
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700年前。
04:22
700 years年份 ago.
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直到500年前,
04:23
And it was only
as recently最近 as 500 years年份 ago
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它才移动到了我们今天熟悉的河道。
04:26
that it occupied占据 the pathway
that we're familiar with today今天.
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04:30
So these processes流程 are really important重要,
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这些过程十分重要,
04:32
and especially特别 here, this delta三角洲 area,
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特别是这里,这个三角洲,
在这个三角洲里密西西比河
不断漫堤和改道,
04:34
where these river-jumping江跳 events事件
in the Mississippi密西西比州
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于是在陆地和海洋的交界处
形成了(新的)陆地。
04:38
are building建造 land土地 at the interface接口
of the land土地 and the sea.
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这是非常宝贵的资产,
04:41
This is really valuable有价值 real真实 estate房地产,
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像这样的三角洲是我们星球上
人口最稠密的地区。
04:43
and deltas三角洲 like this are some of the most
densely密地 populated人口稠密 areas on our planet行星.
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所以了解这些地形的动态变化,
04:48
So understanding理解 the dynamics动力学
of these landscapes景观,
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它们如何形成,在未来将如何继续演化
04:51
how they formed形成 and how they will
continue继续 to change更改 in the future未来
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对于生活在那里的人们十分重要。
04:54
is really important重要
for the people that live生活 there.
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04:57
So rivers河流 also wiggle摆动.
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河流也会轻微摆动。
04:59
These are sort分类 of bigger jumps跳跃
that we've我们已经 been talking about.
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我们刚才谈到的是更大的漫堤过程。
我想向你们展示这里的一些河流摆动。
05:01
I want to show显示 you guys
some river wiggles here.
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我们转移到亚马逊河流域,
05:04
So we're going to fly down
to the Amazon亚马逊 River basin盆地,
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类似的,这里有一个巨大的河流系统,
05:06
and here again we have a big river system系统
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不断冲刷,转移着
安第斯山脉上的物质,
05:08
that is draining排水 and moving移动 and plowing耕作
material材料 from the Andean安第斯 Mountains,
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携带着它们穿越南美大陆,
05:13
transporting传输 it across横过 South America美国
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最终它们被倾入大西洋。
05:15
and dumping倾销 it out
into the Atlantic大西洋 Ocean海洋.
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05:18
So if we zoom放大 in here, you guys
can see these nice不错, curvy曲线玲珑 river pathways途径.
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如果我们在这里放大,
你们可以看到这些蜿蜒曲折的河道。
05:23
Again, they're really beautiful美丽,
but again, they're not static静态的.
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同样的,它们十分美丽,但又不稳定。
这些河流的走向不停扭曲变动。
05:26
These rivers河流 wiggle摆动 around.
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我们可以利用最近30年的卫星图像
05:28
We can use satellite卫星 imagery意象
over the last 30 or so years年份
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05:31
to actually其实 monitor监控 how these change更改.
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来实际观察这是如何变化的。
05:33
So take a minute分钟 and just watch
any bend弯曲 or curve曲线 in this river,
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花点时间看看这条河
任何地方的弯曲,
你会发现它并不会在一个地方呆很久。
05:38
and you'll你会 see it doesn't stay
in the same相同 place地点 for very long.
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它会不断变化,演变,改变图案。
05:41
It changes变化 and evolves演变
and warps经线 its pattern模式.
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05:44
If you look in this area in particular特定,
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如果你再仔细看看这块区域,
05:47
I want you guys to notice注意
there's a sort分类 of a loop循环 in the river
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我想让你们关注到河流中
有一个类似圆圈的地方,
完完全全的被分隔开来了。
05:50
that gets得到 completely全然 cut off.
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05:51
It's almost几乎 like a whip鞭子 cracking开裂
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它就像个马鞭,
从河流的某个位置被分开了。
05:53
and snaps按扣 off the pathway
of the river at a certain某些 spot.
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05:56
So just for reference参考, again,
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方便大家参考,
05:58
in this location位置, that river
changed its course课程 over four miles英里
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在这个地方,河流在一到两个季节里
将它的河道移动了将近四英里。
06:02
over the course课程 of a season季节 or two.
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06:05
So the landscapes景观
that we live生活 in on earth地球,
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所以我们所居住的这个地球上的
地形其实是不断在变化的:
06:08
as this material材料
is being存在 eroded侵蚀 from the mountains
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随着高山上的物质被不断侵蚀,
不断被运输到海洋,
06:10
and transported to the sea,
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地形也在不断地发生变化,
06:11
are wiggling摆动 around all the time.
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它们时时刻刻都在变化着,
06:13
They're changing改变 all the time,
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而我们需要理解这些过程
06:14
and we need to be able能够
to understand理解 these processes流程
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以便于可持续的生存在这些地形之中。
06:17
so we can manage管理 and live生活
sustainably可持续 on these landscapes景观.
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但如果仅仅知道地表发生了什么,
06:20
But it's hard to do
if the only information信息 we have
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仍不足以为可持续的生存指明方向。
06:23
is what's going on today今天
at earth's地球 surface表面.
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我们的观测还不够。
06:25
Right? We don't have
a lot of observations意见.
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例如,我们只有近30年的卫星数据。
06:27
We only have 30 years'年份' worth价值
of satellite卫星 photos相片, for example.
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我们需要更多的观测来
更加深入地了解这些过程。
06:32
We need more observations意见
to understand理解 these processes流程 more.
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此外,我们需要了解
06:35
And additionally另外, we need to know
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随着人类不断占据和改造地表,
06:37
how these landscapes景观 are going
to respond响应 to changing改变 climate气候
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这些地形对气候的变化和
06:40
and to changing改变 land土地 use
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人类对土地的使用将会呈现怎样的反应。
06:41
as we continue继续 to occupy占据
and modify修改 earth's地球 surface表面.
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06:45
So this is where the rocks岩石 come in.
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这就是为什么我们接下来会提到岩石。
06:47
So as rivers河流 flow,
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随着河流流动,
随着它们不断将物质
从高山运送到海洋,
06:50
as they're bulldozing推土 material材料
from the mountains to the sea,
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有的时候一些泥沙和石块会滞留在地面。
06:53
sometimes有时 bits of sand and clay粘土
and rock get stuck卡住 in the ground地面.
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这些留在地面的沙石逐渐被掩埋,
06:56
And that stuff东东 that gets得到 stuck卡住
in the ground地面 gets得到 buried隐藏,
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随着时间的流逝,
便形成了又大又厚的堆积,
06:59
and through通过 time, we get
big, thick accumulations积累 of sediments沉积物
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最终变成了岩石。
07:03
that eventually终于 turn into rocks岩石.
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这意味着,我们可以去到
07:05
What this means手段 is that we can
go to places地方 like this,
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拥有大量沉积岩的地方,
07:07
where we see big, thick stacks
of sedimentary沉积 rocks岩石,
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回到过去,
07:10
and go back in time
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了解过去的地形是什么样子的。
07:12
and see what the landscapes景观
looked看着 like in the past过去.
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从而我们可以重构
07:14
We can do this to help reconstruct重建
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并理解地球的地形演化过程。
07:16
and understand理解
how earth地球 landscapes景观 evolve发展.
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07:22
This is pretty漂亮 convenient方便, too,
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这也非常方便,
07:23
because the earth地球 has had
sort分类 of an epic史诗 history历史. Right?
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因为地球有着宏伟的历史,对吧?
07:26
So this video视频 here
is a reconstruction重建 of paleogeography古地理
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这个视频重构的是地球历史中
最开始的那6亿年的地表演变。
07:31
for just the first
600 million百万 years年份 of earth's地球 history历史.
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07:35
So just a little bit of time here.
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我们花了短短几秒就看完了(笑)。
07:37
So as the plates move移动 around,
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随着板块移动,
我们知道气候变化了,
海平面变化了,
07:40
we know climate气候 has changed,
sea level水平 has changed,
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不同的地形和环境形成了,
07:43
we have a lot of different不同
types类型 of landscapes景观
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07:46
and different不同 types类型 of environments环境
that we can go back --
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我们可以回到过去——
如果有时间机器的话——
07:49
if we have a time machine --
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我们可以回到过去进行观察,
07:51
we can go back and look at,
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而我们确实拥有一台时间机器,
07:52
and we do indeed确实 have a time machine
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我们可以观察这段时间内堆积的岩石。
07:54
because we can look at the rocks岩石
that were deposited沉积 at these times.
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举个例子,带你们到
07:57
So I'm going to give you
an example of this
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地球历史上的一个特殊时期。
07:59
and take you to a special特别
time in earth's地球 past过去.
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大约5500万年前,地球骤暖。
08:01
About 55 million百万 years年份 ago,
there was a really abrupt突兀 warming变暖 event事件,
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当时大量的二氧化碳
08:05
and what happened发生 was
a whole整个 bunch of carbon dioxide二氧化碳
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被释放到了地球的大气中,
08:07
was released发布 into earth's地球 atmosphere大气层,
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这导致了快速并且极端的全球变暖。
08:09
and it caused造成 a rapid快速
and pretty漂亮 extreme极端 global全球 warming变暖 event事件.
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我说的“暖和”是指超级暖和,
08:13
And when I say warm, I mean pretty漂亮 warm,
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那时北至加拿大,南至巴塔哥尼亚,
08:15
that there were things
like crocodiles鳄鱼 and palm棕榈 trees树木
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都能找到鳄鱼和棕榈树。
08:18
as far north as Canada加拿大
and as far south as Patagonia巴塔哥尼亚.
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所以这的确是非常暖和的时期,
而且发生得非常突然。
08:22
So this was a pretty漂亮 warm time
and it happened发生 really abruptly突然.
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我们能做的,
08:25
So what we can do
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就是回到过去,找到当时沉积的岩石,
08:26
is we can go back and find rocks岩石
that were deposited沉积 at this time
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并且重构这些地形是
如何随全球变暖变化的。
08:29
and reconstruct重建 how the landscape景观 changed
in response响应 to this warming变暖 event事件.
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08:33
So here, yay好极了, rocks岩石.
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这里,太好了,有岩石。
08:35
(Laughter笑声)
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(笑声)
这是一堆岩石。
08:37
Here's这里的 a pile of rocks岩石.
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这里黄色圈出的一片,
08:39
This yellow黄色 blobBLOB here,
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其实是一条古河道,
08:41
this is actually其实 a fossil化石 river,
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就像我刚才展示的卡通一样,
08:43
so just like this cartoon动画片 I showed显示,
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这些是5500万年前留下的沉积物。
08:44
these are deposits存款 that were
laid铺设 down 55 million百万 years年份 ago.
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作为地质学家,
我们可以近距离的观测它们,
08:48
As geologists地质学家, we can go
and look at these up close
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并且重构地形。
08:51
and reconstruct重建 the landscape景观.
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08:53
So here's这里的 another另一个 example.
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还有一个例子。
08:54
The yellow黄色 blobBLOB here is a fossil化石 river.
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这黄色范围内的一片是古河道。
在它上面还有一片。
08:57
Here's这里的 another另一个 one above以上 it.
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我们可以到实地仔细考察、测量,
08:58
We can go and look in detail详情
and make measurements测量 and observations意见,
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还可以观测它们的特征。
09:02
and we can measure测量 features特征.
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例如,我刚刚标注的地方
09:03
For example, the features特征
I just highlighted突出 there
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告诉我们这条河大约3英尺深。
09:05
tell us that this particular特定 river
was probably大概 about three feet deep.
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如果你生活在5500万年前,
09:09
You could wade
across横过 this cute可爱 little stream
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你可以涉水通过这条萌萌的小溪。
09:11
if you were walking步行 around
55 million百万 years年份 ago.
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09:14
The reddish stuff东东 that's above以上
and below下面 those channels渠道,
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在这些渠道之上和之下的红色物质,
09:17
those are ancient soil deposits存款.
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是古代的土壤沉积。
我们可以通过它们知道在这片土地
生活和生长着什么样的生物,
09:19
So we can look at those to tell us
what lived生活 and grew成长 on the landscape景观
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并且了解这些河流是如何和
冲积平原相互影响的。
09:23
and to understand理解 how these rivers河流
were interacting互动 with their floodplains漫滩.
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09:27
So we can look in detail详情
and reconstruct重建 with some specificity特异性
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我们可以仔细的观测,准确的重构
这些河流的走向,以及地形的样貌。
09:32
how these rivers河流 flowed流入
and what the landscapes景观 looked看着 like.
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现在当我们为这个地区重构过去的
09:34
So when we do this
for this particular特定 place地点
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09:38
at this time,
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地形时,
如果我们看看
在这次突然变暖之前发生了什么,
09:39
if we look what happened发生
before this abrupt突兀 warming变暖 event事件,
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这些河流从高山到海洋开辟了一条道路,
09:42
the rivers河流 kind of carved their way
down from the mountains to the sea,
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看上去和我向你们展示的
亚马逊流域很像。
09:45
and they looked看着 maybe similar类似 to what
I showed显示 you in the Amazon亚马逊 River basin盆地.
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但是气候变化刚一开始,
09:50
But right at the onset发病
of this climate气候 change更改 event事件,
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这些河流就发生了剧变。
09:53
the rivers河流 change更改 dramatically显着.
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09:55
All of a sudden突然 they got much broader更广泛,
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首先它们一下子就变宽了许多,
09:57
and they started开始 to slide滑动 back and forth向前
across横过 the landscape景观 more readily容易.
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其次它们在地表上的
改道活动更加频繁。
10:01
Eventually终于, the rivers河流 reverted回复
back to a state that was more similar类似
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最终,这些河流变回了
10:05
to what they would have looked看着 like
before this climate气候 event事件,
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气候变暖之前的样子,
但这花了很长很长的时间。
10:09
but it took a long, long time.
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10:12
So we can go back in earth's地球 time
and do these kinds of reconstructions重建
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我们可以回到地球的过去,
做类似的重构,
10:16
and understand理解 how
earth's地球 landscape景观 has changed
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了解地表是如何随着气候变化,
如之前提到的地球骤暖
或土地使用的变化而变化的。
10:18
in response响应 to a climate气候 event事件 like this
or a land土地 use event事件.
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河流产生变化一些方式,
10:22
So some of the ways方法 that rivers河流 change更改
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或是改变走向和水文活动的原因,
10:24
or the reasons原因 that rivers河流 change更改
their pattern模式 and their movements运动
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有一些是因为当地表有了更多的水,
10:29
is because of things like with extra额外 water
falling落下 on the land's土地的 surface表面
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再加上气候变暖,
10:33
when climate气候 is hotter,
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沉积物会被更加频繁地被运送或侵蚀,
10:35
we can move移动 more sediment沉淀
and erode侵蚀 more sediment沉淀,
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这些都会对河流产生影响。
10:37
and that changes变化 how rivers河流 behave表现.
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10:40
So ultimately最终,
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总而言之,
10:42
as long as earth's地球 surface表面 is our home,
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只要地球是我们的家园,
我们就需要小心的管理资源,
10:45
we need to carefully小心 manage管理
the resources资源 and risks风险
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警惕生活在这种动态环境中的风险。
10:48
associated相关 with living活的
in dynamic动态 environments环境.
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我认为我们能真正持续
这么做的唯一途径
10:51
And I think the only way
we can really do that sustainably可持续
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是充分考虑在地球历史的
10:55
is if we include包括 information信息
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慢慢长河中,地形的演变和走向。
10:58
about how landscapes景观 evolved进化
and behaved in earth's地球 past过去.
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谢谢。
11:02
Thank you.
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(掌声)
11:03
(Applause掌声)
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Translated by Lipeng Chen
Reviewed by Hongmeng Yang

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ABOUT THE SPEAKER
Liz Hajek - Geoscientist
Liz Hajek studies sedimentary rocks to understand how landscapes change and evolve.

Why you should listen
Liz Hajek's research has contributed new perspectives on how rivers and coastlines move and how sediments record earth history. She is an assistant professor of geosciences at The Pennsylvania State University, where she teaches a range of courses spanning topics from oceanography to petroleum geology. Hajek and her students often conduct fieldwork in rugged places and use computer models and experiments to reveal the rhythms and dynamics of earth's surface. She recently appeared in the NOVA Treasures of the Earth: Power episode and has a paper in the Annual Review of Earth and Planetary Sciences.
More profile about the speaker
Liz Hajek | Speaker | TED.com