ADM-201 dump PMP dumps pdf SSCP exam materials CBAP exam sample questions

地质学 – 译学馆
未登录,请登录后再发表信息
最新评论 (0)
播放视频

地质学

Geology

Hi. It’s Mr. Anderson
大家好 我是Anderson
and this is environmental science video 3.
这是环境科学第三期
It is on geology,
本期讲地质学
which is the study of rocks and how they change over time.
即研究岩石及其随时间的变化
And in this class more appropriately
确切地说 本堂课在讲
how that affects human society.
岩石的变化如何影响人类社会
Now the problem with rocks is that they change slowly.
问题是岩石变化进程非常缓慢
They change over geologic time
它们随地质年代改变
and we simply do not live long enough to see all of these changes occur.
这些改变慢到我们一辈子也察觉不到
You could imagine how this sandstone is being shaped by the wind
你能想象这块砂岩怎样被风塑形
but you cannot see it.
但看不到
And it is not until we see lava
直到我们看到熔岩
that we really start to understand the dynamic earth.
我们才真正开始明白动态的地球
And to understand these systems on the earth
要想理解地球上的这些系统
we should really understand how the earth is put together.
我们需要明白地球是如何被组合起来的
And so if we look at the layers,
如果观察地球的分层
on the inside we have the inner and outer core.
地球内部分为内核和外核
We then have the mantle and finally we have the crust.
然后是地幔 最外面是地壳
And we live on the crust.
我们生活在地壳上
And we have only been able to
并且我们只能够
dig just a little bit into the crust.
往地壳内挖一点点
And so we have been able to figure out everything else
通过分析地震波在地层中的传播
by looking at how earthquake waves move through the earth.
我们可以知道任何地层的结构
And we know this,
我们知道
that the crust is made up of rocks and minerals.
地壳由岩石和矿物组成
Rocks are made of minerals,
矿物组成岩石
which in turn are made of molecules and atoms.
矿物又由分子和原子组成
They are constantly being reshaped.
岩石不断被重塑
And we can measure that through the rock cycle.
我们可以在岩石循环中探究这个过程
But crust itself is made up of these large continental and oceanic plates.
而地壳本身由巨大的大陆和大洋板块组成
And they float on the mantle itself.
这些板块漂浮在地幔上
And so this is rock under here,
所以这个位置上应该是岩石
but it is rock that is moving.
但是它是可移动的
As we generate heat,
随着产生热量
as it moves up, it is pushing those plates around.
岩石不断上移并推动着周围的板块
They move very slowly,
他们移动地非常慢
about the same rate that your fingernails grow.
大约和你的指甲生长速度相同
But they have huge force and therefore huge impacts.
但是它们推力极大 能产生巨大影响
And so when those plates run into each other we have boundaries.
板块相撞时会产生板块边界
An example of that would be the ring of fire.
太平洋火山带就是一个例子
So if you look around the Pacific Ocean
所以如果你观察太平洋
you have this area where almost all of the earthquakes and volcanoes take place.
会发现几乎所有地震和火山活动都在这儿
We also have what are called hot spots.
板块运动也能形成“热点”
And those are going to be areas where
板块经过地幔热区上方
a plate will move over a hot area in the mantle,
板块上对应的区域就成了热点
and we can form islands like Hawaii.
夏威夷之类的岛就这样形成
Now if we look at where those boundaries
如果观察板块边界
occur we will have structures like volcanoes and mountain chains.
我们会发现火山或者山脉
But we will also therefore
但这也会使得
have hazards around those areas
这些区域发生灾害
where it can impact human society
由此影响人类社会
and we will discuss a lot of those.
我们将对此细致讨论
And so to understand what is going on on the earth
所以要理解地球上正在发生什么
we should really understand what it looks like on the inside.
我们应该知道地球内部是什么样的
So we have a solid inner core,
地球有固体内核
a liquid outer core and
液态外核
then we have what is called the mantle.
还有被称为“地幔”的东西
Now around 85 percent of the volume of the earth
大约85%的地球体积
is going to be in this mantle.
都被地幔占据
So it is rock, but it is rock that is moving.
地幔也是岩石 但它也会移动
We are generating a huge amount of heat down here.
这下面产生着巨大的热量
And then we finally get up to what is called the crust.
最后是我们所说的“地壳”
That is where we live.
我们就生活在这里
And so on that crust we have rocks.
而地壳上面有岩石
And those rocks are constantly
岩石不断塑造转化
being shaped from one into another.
从一种形态变成另一种形态
And so if we take a look at this rock cycle,
我们来看一下岩石循环
since it is a cycle you could start anywhere.
这是个循环 哪开始都可以
Let’s start with an igneous rock.
我们从岩浆岩开始
So an igneous rock,
岩浆岩
like granite,
如花岗岩
is going to be formed when we have crystallization of magma.
是岩浆结晶后形成的
as it crystallizes you can see those crystals right here.
结晶时你可以在它上面看到晶体
So this granite is made up of minerals.
花岗岩由矿物构成
So I can see for example this quartz
比如我可以看到石英
and this pink feldspar and we have this mica.
粉红色的长石 还有云母
So these are the minerals that make up the rock itself.
这些都是组成岩石的矿物
But, this could experience erosion.
但是岩石可能会受到侵蚀
So erosion on the planet, water, wind,
地球上水 风之类的侵蚀
can cause it to break down into sediments.
会使岩石分解 化为沉积物
therefore after it has done that it could get squeezed
这个过程之后 沉积物会被挤压
for a long period of time and
持续很久后
we could have a sedimentary rock,
沉积岩就形成了
which is going to be compressed sediments.
这种石头是被压实的沉积物
Now that it could be squeezed,
既然它能被挤压
we could squeeze it under the surface of the earth using heat and pressure.
在地表下的热量和压力作用下
It could form something like quartzite.
它会变成类似石英岩的岩石
Or we could take that igneous and we could squeeze and
或者对岩浆岩进行挤压
make something like gneiss.
形成类似片麻岩的物质
And so g-n-e-i-s-s,
片麻岩拼作g-n-e-i-s-s
it is a type of metamorphic rock
它是一种变质岩
that is formed by the squeezing of granite.
由花岗岩挤压形成
Now you can see those minerals are still there
你看到的矿物还在
but has a different shape.
只是以不同的形态
And so the rocks on our planet
所以地球上的岩石
are continually recycled over and over and over again.
在持续循环 周而复始
But if we get back to the structure of the earth,
但是如果我们回到地球结构上
what is driving all of this
驱动所有这一切的
are going to be convection currents within the mantle itself.
将是地幔里的对流
And so if you look at this and say this is some boiling water,
请看这缸沸水
so if we generate a little bit of heat underneath it,
假设在下面稍稍加热它
that heat is going to be transferred through the water,
热量就会通过水传播
so if you held your hand up here
当你把手伸到上方时
you would feel some of that heat above it.
你就会感受到水上面的热量
But if we look inside the water itself
如果我们观察水的内部
we are going to have these convection currents,
就会发现一些对流
areas where we are heating it up.
这是我们加热的地方
And so we are decreasing the density
水密度在这降低
and then it cools down and then it is going to sink again.
水冷却后又再次下沉
So we are going to find the same thing in the mantle itself.
而我们会在地幔里发现相同的现象
It does not occur as quickly
但是这种现象
as it does in the boiling water,
不像沸水中那样发生那么快
but it has huge implications on the crust above.
但它将对上面的地壳产生巨大的影响
So if we look at that crust it is actually made up of plates.
我们观察地壳就会发现它由板块组成
And so if I trace out a plate like this,
我描出了这样一个板块
this would be a continental plate.
这是个大陆板块
And so it is being pushed to the left
这个大陆板块被往左推动
and the reason why it is being pushed is
它为什么被这样推动呢
because this convection current is moving like that.
是因为对流促使板块这样移动
It is forcing the plate in that direction.
它推动板块按这个方向移动
And it is running into another plate.
这个板块撞上另一个板块
So we have an oceanic plate.
这是个大洋板块
The oceanic plates are going to be more dense
大洋板块将变得更密实
and they will be pushed underneath a continental plate.
它们被推到大陆板块下面
And what we are going to get, right along this
我们可以进一步看到
margin is going to be a convergent plate boundary.
顺着这个边缘将有一个汇聚板块边界
They are running into each other.
两个板块会相撞
But we could look over here
但我们看看这里
and maybe there is another oceanic plate that is moving in the other direction.
或许另一个大洋板块往其它方向移动
Why is it moving in the other direction?
为何它如此移动呢?
Because the convection current is pushing it here.
因为对流正在把它推向这里
Or pushing it there.
或者那里
And so we could have this mid-Atlantic ridge or this mid-oceanic
所以地球上有大西洋中脊
ridge being formed right there.
大洋中脊
So we have known this for a long time.
众所周知
If you look at the ring of fire,
如果你研究火山带
we find around the Pacific Ocean we have an aggregation of volcanoes and earthquakes,
就会发现太平洋周围是火山和地震聚合带
something like 75 percent of all volcanoes,
世界上75%的火山爆发
90 % of earthquakes are found in this area.
90%的地震都出现在此地区
If we start plotting where those
标出地震发生地
earthquakes are we can start to see where
我们就会发现它们正好存在于
those plates exist.
板块的位置
And if we look at the plates on our planet it is hard to wrap your
如果我们观察一下地球上的板块
head around this picture for a second.
你恐怕没法立刻弄明白
So this is North America right here.
这是北美洲
And it sits on this giant north american plate.
坐落在巨大的北美洲板块上
And then we would have the pacific plate right here.
然后这里是太平洋板块
And so those plates are constantly moving around.
这些板块都在不停地移动
You are probably familiar with Pangea
你可能熟悉“泛大陆”
which was a time when all of the continental plates had come together.
那时所有大陆板块都合在一起
So what happens when plates meet is
那么当板块相遇会发生什么呢
that they can do one of three things.
有三种事情可能发生
They can slide past one another
它们会在转换边界
in this transform boundary.
彼此滑动
They could move apart.
它们会分开
We call that a diverging boundary or
我们称之为离散边界
they could run into each other.
它们会互相碰撞
That is converging.
那种是汇聚
And so if we look at an example of that, right
我们来看一个例子
here we have a convergent plate boundary.
这是一个汇聚边界
So what is going on?
那会发生什么
We have this oceanic plate,
这是大洋板块
which is being pushed of subducted underneath a continental plate.
它将被推拉到大陆板块下面
I described that just a second ago.
我刚描述过这种情况
What is happening is we are melting that rock
岩石将会被熔化
and that is forming this volcano chain
进而沿着这里
that goes all the way back here.
形成火山链
An example could be the Cascades in Washington state.
还有一个例子 在华盛顿州的卡斯卡德斯
We could also have a convergent boundary right here
这里也有一个汇聚边界
where you have an oceanic plate going underneath another oceanic plate.
这里的一块大洋板块深入另一块下方
And we get this island arc like the Aleutian Islands in Alaska.
这个弧形列岛就像阿拉斯加的阿留申群岛
We could have divergent boundaries.
这里是离散边界
An example could be right here.
一个例子如下
So we have this oceanic plate moving away
两个大洋板块背向移动
from this oceanic plate so we get this mid-oceanic ridge.
就形成了大洋中脊
We could have a rift valley
当大陆板块被撕开时
where this continental plate is being pulled apart.
就会产生裂谷
We could have transformed boundaries.
就有了转换边界
Here would be an example where they are sliding past one another.
下面再举一个板块彼此划过的例子
San Andreas fault is a good example of that.
圣安德烈亚斯断层就是代表之一
But we could also have structures where this no boundary.
但也有不在边界的地质结构
So if we look right here we have what is called a hot spot.
看这里 这个被称为“热点”
Remember that is going to be an area where
请记住 这里是
the mantle is close to the surface.
地幔接近地表的区域
And so for example
比如
Hawaii was formed as the plate slid over a hot spot.
热点上的板块滑动形成了夏威夷
And let me show you what that looks like.
我来展示下原理
So if we imagine that is the hot spot,
假如这就是那个热点
it is going to be underneath the plate and
它位于板块之下
what has happened to Hawaii over time,
随着时间的流逝
is it slowly slid over the hot spot.
夏威夷渐渐滑过热点
Hot spot stays in the same location.
热点待在相同的位置
And so we have had volcano after volcano after volcano.
所以这里会有接二连三的火山爆发
And so this the most recent volcano and
而这是最近的火山爆发
we will have another island right here.
就在此处会产生另外一个岛屿
And the reason they are smaller islands out here is that there is more erosion.
它们是小岛的原因是这里有过更多的侵蚀
Yellowstone National Park is another example
黄石国家公园在另一个热点上
of a hot spot and a plate simply sliding over the surface.
也是由板块滑过地球表面形成
Now we get to humans and human society and
现在我们来看人类和人类社会
how we start to interact with the structures of the earth.
是如何开始和地球结构互相作用的
And so living around these boundaries can be dangerous.
而住在板块交界处是危险的
It is just a matter of time.
这只是时间问题
And so an example could be volcanoes.
举一个有关火山的例子
Some volcanoes, like the ones we would find in
一些火山 比如夏威夷的火山
Hawaii can ooze out.
会不时喷发
And as long as we are able to move out of there quickly
只要能快速离开
we are going to be fine.
我们就会没事
But some are highly explosive.
但是一些火山极度活跃
And it depends on what minerals make up that
构成岩石的矿物
rock that determines the explosiveness of the volcano.
决定了火山爆发是否剧烈
A very explosive one I remember
有个很活跃的
was Mount St. Helens.
叫圣海伦斯山
And so this is a picture of Mount St. Helens in Washington.
这是一张圣海伦斯山的图片
This is the day before it exploded.
拍摄时间是它爆发之前那天
And so just take a second to imagine that is the structure
所以短暂想象一下火山的结构
of the volcano and now it is gone and rebuilding again.
现在它没了 又开始再次重塑
And so it literally blew apart.
所以说 它完全炸掉了
If you were on or near that you died.
所以如果你在附近你就死了
Earthquakes are another example of a natural hazard.
地震是另一种自然灾害
We have our faults and this would be a fault right here.
我们有断层示意图 这个就是
And we have one plate, in this
这里发生了断层
case transformed fault, where it is sliding past one.
这种是平移断层 即两个断层平行错开
We could also have a divergent boundary,
这种离散边界
so these two are moving away from each other.
两个断层上下错开
And so we have what is called a normal fault.
这种还叫做正断层
It is slipping down.
它在向下滑开
Or we could have a reverse or thrust fault,
我们还有逆断层或冲断层
when we have an convergent
这个断层两边的区域
between these two areas on either side of the fault.
是会聚性的
Now the names are not as important.
它的名字不重要
Really understanding what is going on in an earthquake is.
只需明白地震这样发生
If you think about it, if we
请你想象
have two plates that are pushing
两板块挤住
on each other eventually they are going to build up pressure
最后产生压力
and it is going to slip.
然后就会滑动
And as it does that we have an earthquake.
这样就会产生地震
So if we watch this right here,
请看这张图
let’s say there is pressure in this direction,
假如往这个方向有个压力
in this direction and eventually it builds up
最终这个压力会增强
and we have a slide along that fault line.
然后板块会在断层线处滑动
Now it is not like it stopped.
这次滑动后板块不会停
There is still pressure there.
那里仍然有压力
We could have another earthquake in the future.
未来可能发生第二次地震
And another earthquake in the future.
第三次地震也未来可期
As these move past each other
当板块彼此滑过时
it is just going to move in small slips.
只会滑动很小的距离
And every time we do we have an earthquake.
但每次滑动都会引发地震
Now if you are standing on the surface and
若此时你站在地面上
there is an earthquake you are going to be fine.
就算发生地震也不会有事
The problem is if we build structures
但地震处若造有建筑
on that and it is not earthquake ready then those fall
且没有为地震做准备 他们就会倒塌
in and humans are going to be impacted.
人类将受到很大的影响
We could also look at tsunamis which are caused by earthquakes.
我们还可以看到地震还引发了海啸
What we have here is a subducting oceanic plate.
这是一个俯冲海洋板块
This would be a continental plate.
而这个是大陆板块
And what is happening is this is being
接下来会发生的是
pushed underneath, but it will just stick.
它冲到下面 被卡住
And so it is not going to release.
这样死死卡住
And it sticks then we build up pressure.
卡住后会积攒压力
And eventually when it slips what
最终两个板块出现滑动时
we get is a huge push up on the water above it.
上面的水会受到巨大的推力
So you get this vertical motion
海水会垂直运动
in the ocean and that leads to these giant tidal waves.
进而导致巨大的海浪
And so if you are near the ocean
所以如果你在海洋附近
you would also suddenly notice the ocean is going way
你会突然发现海浪上下起伏
out and then it is going to come way in and there are really bad consequences
产生巨大颠簸 会带来恶劣的结果
from that. We could also have mass wasting.
这会给我们造成巨大的损失
So an example could be a landslide moving across this road.
一个例子就是山体滑坡造成的路面毁损
This is a picture taken before and then watch it, after a landslide.
请看这两张取景自山体滑坡前后的照片
Now it does not occur really quickly.
但是这不会瞬间发生
It could be triggered by an earthquake, but generally
它会由地震引发
if we get a lot of water in an area,
但是如果那还有很多水
it can not support that weight.
就无法承重这么多了
And so did you learn about earth systems?
现在你了解地球系统了吗?
Can you stop the video and try to fill in the blanks right now?
现在你能停下视频填写这张表格了吗?
I would pause the video.
我会停下视频
But if not, I would say we have a center core.
但是若你不能 我提示你这是地心
We have a mantle and a crust.
还有地幔和地壳
The crust is made up of rocks which
地壳由岩石组成
in turn are made up of minerals, which
岩石由矿物组成
is reshaped using the rock cycle.
在岩石循环中被重塑
These plates move on the surface.
这些板块在地表移动
We call that plate tectonics.
我们称之为板块构造论
An example would be the ring of fire.
火山带就是一个例子
Where we have boundaries we can build up structures
在板块边界 会有一些地质活动
like volcanoes, mid-oceanic ridges.
比如火山 大洋中脊
But we could also have natural hazards.
还会发生一些自然灾害
And remember not along boundaries,
记住不要待在板块边界
but just within the plate we can have hot spots.
但就算板块内部也有热点
So I hopeyou learned all of that.
愿你对这些都已了解
And I hope that was helpful.
有所禆益

发表评论

译制信息
视频概述

简述了地球上的岩石循环,板块构造与板块边界,热点、火山、海啸和地震。

听录译者

收集自网络

翻译译者

饼干

审核员

审核员_ZB

视频来源

https://www.youtube.com/watch?v=acwSG17e_lQ

相关推荐