风化

Lesson Objectives
::经验教训目标

• Define mechanical and chemical weathering.
  ::界定机械和化学天气预报。

• Discuss agents of weathering.
  ::讨论天气预报的代理商。

• Give examples of each type of weathering.
  ::举例说明每种类型的天气预报。

Lesson Vocabulary
::词汇表课程

• abrasion
  ::镜体

• chemical weathering
  ::化学风化

• erosion
  ::侵蚀

• ice wedging
  ::结冰

• mechanical weathering
  ::机械气象

Introduction
::导言

Have you ever heard the term weathering? It may not be what you think. Weathering does not explain the conditions at a certain place. That would be weather. The terms sound alike, but they are different.  Weathering  refers to the breaking apart of rocks. Rocks and even entire mountains are slowly broken up by the process of weathering.  Erosion  is the process that moves these broken pieces. Weathering and erosion work together to reshape the land. Weathering occurs on or near Earth's surface.  
::你曾听见这个说法吗?它或许不是你们所想的。天气不能解释某一地方的条件。那是天气。声音是一样的,但不一样。天气是指岩石的裂缝。岩石甚至整个山峰都因天气变暖过程而慢慢断裂。侵蚀是这些破碎的碎块移动的过程。天气和侵蚀合力重塑土地。天气发生在地球表面或地球表面附近。

What Is Weathering?
::什么是"天气预报"?

Weathering breaks down rocks into smaller pieces. These small pieces of rock are called sediment. Sediments can be any size and shape. Giant boulders can be sediments. They may have started as part of a mountain and then broken up. You may have small decorative rocks around your home. These too came from even larger rock. Therefore, they have been through the process of weathering. Even soil has been broken down from larger and larger rocks.
::天气使岩石破碎成小块。 这些小块岩石被称为沉积物。 沉积物可以是任何大小和形状。 巨型巨石可以是沉积物。 巨型巨石可以是山体的一部分, 可能从山体开始, 然后碎裂了。 你家周围可能有小块装饰石块。 这些石块也来自更大的岩石。 因此, 它们经历了气候变暖的过程。 甚至土壤也从更大的岩石中碎裂了。

It takes a long time for a rock or mountain to weather. Have you ever traveled to a colder part of the world? If so, you may have noticed all the holes in the roads. These holes appear in the spring after a cold winter ( Figure   ). This breaking apart of the roadway is a form of weathering. Its causes are the same as what happens to large mountains. The difference is that a road can change more quickly.  
::一座岩石或一座山要花很长的时间才能天气。 你曾经去过世界寒冷的地区吗?如果是的话,你可能已经注意到了道路中的所有洞穴。这些洞穴在寒冬过后出现在春天(图 ) 。 路道的破碎是一种天气形式。 其原因与大山发生的情况相同。 不同之处在于道路可以更快地改变。

Mechanical Weathering
::机械气象学

Mechanical weathering  breaks rock into smaller pieces. These smaller pieces are just like the bigger rock. They are just smaller! The rock is still the same type of rock. It has not changed into a different kind of rock. The smaller pieces have the same minerals. They are also in the same proportions. You could use the expression “a chip off the old block“ to describe this type of weathering! The main agents of mechanical weathering are water, ice, and wind.
::机械风化将岩石破碎成小块。 这些小块与大块的岩石一样, 它们只是小块的。 岩石仍然是同样的岩石类型。 它没有改变为不同的岩石类型。 小块的矿物质相同, 比例也相同 。 您可以使用“ 旧块上的芯片” 来描述这种天气类型 。 机械风化的主要动力是水、 冰和风 。

Ice Wedging
::冰 冰 结 织

How do you think ice plays a role in breaking apart a rock? Ice is just the solid form of water. Ice is not harder than a rock, so how can it be the cause of weathering? It's simple really, water is special.
::你认为冰如何在打破岩石中扮演角色?冰只是水的固态形式。冰并不比岩石更难,所以它如何成为气候变暖的原因?很简单,水是特别的。

Water is very unique. On Earth, it can exist in all three states. It can be a liquid at room temperature. When heated, it changes into a gas. Even more interesting is when it becomes a solid. When liquid water changes into ice, it actually gets larger. It is this change that causes ice wedging.  Ice wedging  is common in cold climates. It can also be found in mountainous regions.  
::水是非常独特的。 在地球上,它可以存在于所有三个状态。 它可能是在室温下的一种液体。 当加热时, 它会变成一种气体。 更有趣的是当它变成固体时。 当液体水变成冰时, 它实际上会变大。 正是这种变化导致了冰结。 冰结在寒冷的气候中是常见的。 它也可以在山区找到。

How does ice wedging occur? First, liquid water is needed to begin the process. Liquid water runs into the crack in the rock. This happens when the temperatures are above freezing. As temperatures drop below freezing, the liquid water turns to ice. During this physical change, the water expands. This expansion is what breaks apart the rock. You can see this effect when you fill an ice cube tray with water and put it in the freezer. Note the level of the water in the tray. With time, the water freezes into ice. You can now see the ice will be at a higher level in the tray.
::如何结冰? 首先, 需要液态水才能开始这一过程。 液态水会进入岩石的裂缝中。 当温度高于冰层时, 液体水会变成冰。 当温度降低到冰层以下时, 液体水会变成冰。 在这种物理变化中, 水会膨胀。 膨胀是打破岩石的原因。 当您用水填满一个冰块盘并把它放在冰柜中时, 您可以看到这种效果。 注意托盘中的水水平。 随着时间的推移, 水会冻结在冰中。 现在可以看到冰在托盘中的温度会更高 。

Have you ever put a can of soda in the freezer? Have you left it there accidentally? What happened or what do you think might happen? Yes, it will expand. If you are lucky, the can will bulge. If you are unlucky, the can may have split open. (For the record, water is very unusual. Most substances get smaller when they get colder.)
::你曾没有在冰箱里放一罐苏打水呢?你曾无意地把水放在那里吗?你曾以为会发生什么事呢?你曾以为会怎样呢?是的,它会膨胀。如果你运气好,那罐水就会膨胀。如果你运气不好,那罐水就会裂开。(如果你们运气不好,那罐水就裂开。)

Over time, freezing and thawing of water forces the rock apart. Ice wedging is very good at breaking apart rocks. Look around and you may find some evidence at the base of a mountain slope. You will probably find large piles of broken rock at the base of a slope. These rocks were broken up by ice wedging. Once loose, they tumbled down the slope.
::随着时间的推移, 冰冻和水的解冻迫使岩石分解。 冰结会拆解岩石。 冰结会很好地拆解岩石 。 环顾四周, 您可以在山坡底找到一些证据 。 您可能会在山坡底找到一大堆破碎的岩石 。 这些岩石是被冰结拆开的。 一旦松散, 它们就会从山坡上掉下来 。

Abrasion
::面部

Abrasion  is another type of weathering. Like ice wedging, it is a form of mechanical weathering. Like ice wedging, abrasion does not change the rock into another type of rock.
::磨损是另一种类型的天气变迁。 就像冰层变形一样,它是一种机械变形。 像冰层变形一样,磨损不会将岩石变成另一种类型的岩石。

With abrasion, one rock or piece of sediment bumps against another rock. Rocks don't normally roll around on their own, so why do they move? There are a couple of reasons a rock may move.
::岩石通常不会自行滚动,为什么它们会移动?岩石移动有几个原因。

Gravity can cause rocks to move. They may roll downhill or fall off a cliff. As they roll down a hill, they bump into each other. Maybe a moving rock hits a rock that is not moving at the bottom of the hill. 
::引力可导致岩石移动。 它们可能会滚下山坡或从悬崖上坠落。 当它们滚下山坡时,它们会相撞。 也许移动的岩石撞到一块没有在山底移动的岩石。

Moving water causes rocks and sediment to move.  Rocks are bounced along the bottom and bump against one another ( Figure   ). As they collide, they begin to chip away at each other. Angular rocks become more rounded with each collision.  
::移动水导致岩石和沉积物移动。岩石沿底部反弹并相互碰撞(图 ) 。 当它们相撞时,它们开始相互碰撞。 每次碰撞时,角岩会变得更圆。

Strong winds cause abrasion. The wind carries sediment. This sediment is thrown against other rocky surfaces by the wind. It is like sand-blasting a rock. 
::强风造成磨损,风携带沉积物,这种沉积物被风抛向其他岩石表面,就像砂状岩石。

Finally, the ice in glaciers causes abrasion. Pieces of rock embedded in ice grind away at the rock below. Have you ever collected beach glass? Maybe you have seen rounded pebbles in the bottom of a stream? If so, you have witnessed the work of abrasion.
::最后,冰川中的冰块造成了磨损。 岩石被冰块困在下面的岩石上。 你收集过海滩玻璃吗? 也许你见过溪底的圆形石块吗? 如果是这样, 你见过磨损的痕迹。

Plants and Animals in Mechanical Weathering
::机械气象中的植物和动物

Sometimes plants and animals cause weathering. This can happen slowly. A plant's roots grow into a crack in rock. As the roots grow larger, they wedge open the crack. You can see this in action by looking at sidewalks. Smalls plants grow in the cracks. Over time, the plants can grow large enough to break apart the concrete. 
::有时,植物和动物导致天气变暖。这可以慢慢发生。植物的根部会长成岩石裂缝。当根部变大时,它们会将裂缝隔开。你可以通过观察人行道看到这一点。小植物会生长在裂缝中。随着时间的推移,植物会长得足够大,可以拆解混凝土。

Burrowing animals can also cause weathering. Animals may dig for food or create a hole to live in. This process may cause rock to break apart. 
::栖息动物也可以造成天气变暖。 动物可以挖食物或创造洞住。 这一过程可能会导致岩石分裂。

Today, human beings do a lot of weathering of rocks. They dig and blast rock for many purposes. Small pieces of rock and sediment are needed for the building of homes and roads. Places where humans break apart large rocks into smaller ones are called quarries. 
::今天,人类经常对岩石进行风化,他们为许多目的挖掘和爆破岩石,建造房屋和道路需要小块岩石和沉积物。 人类将大块岩石拆成小块岩石的地方被称为采石场。

Chemical Weathering
::化学天气预报

Chemical weathering  is different to mechanical weathering. The minerals in the rock change. The rock changes composition. The rock becomes a different type of rock. 
::化学天气与机械天气不同。岩石中的矿物变化。岩石的构成变化。岩石变成一种不同的岩石类型。

There are many agents of chemical weathering. Remember that water is a main agent of mechanical weathering. Water is also an agent of chemical weathering. That makes it a double agent! Carbon dioxide and oxygen are also agents of chemical weathering. Each of these is discussed below.
::有很多化学气化剂。 记住水是机械气化的主要剂。 水也是化学气化的一种剂。 这使得它成为一种双重剂! 二氧化碳和氧气也是化学气化的剂。 以下将讨论其中的每一种。

Water
::水 水

Water is an amazing molecule. It has a very simple chemical formula, H ₂ O. It is made of just two hydrogen atoms bonded to one oxygen atom. Water is remarkable. It is able to do many things. It can exist in three forms on Earth. It can freeze and expand. Lots of things dissolve easily in water. Some types of rock can even completely dissolve in water! 
::水是一个惊人的分子。 它有一个非常简单的化学方程式, H2O。 它由两个氢原子组成, 连接到一个氧原子。 水是惊人的。 它能做很多事情。 它可以以三种形式存在于地球上。 它可以冷冻和膨胀。 许多东西很容易在水中溶解。 有些类型的岩石甚至可以完全溶解到水中 。

Weathering Happens at Different Rates
::不同比率的天气状况

Each type of rock weathers in its own way. Certain types of rock are very resistant to weathering. Igneous rocks tend to weather slowly as they are hard. Water cannot easily penetrate them. Granite is a very stable igneous rock. Other types of rock are easily weathered. They dissolve easily in weak acids. Limestone is a sedimentary rock. It dissolves easily. When softer rocks wear away, more resistant rocks are left behind. These more resistant rocks form ridges or hills.
::每种类型的岩石天气都以自己的方式。 某些类型的岩石非常耐不住天气。 某些类型的岩石往往会缓慢地经受严酷的天气; 水不容易渗透它们。 巨石是一个非常稳定的有皮质的岩石。 其他类型的岩石很容易被风化, 它们很容易在微弱的酸中溶解。 利姆斯通是一个沉积的岩石。 它很容易溶解。 当较软的岩石消失时, 更耐抗力的岩石会落在后面。 这些较耐力的岩石形成脊或山丘。

Devil's Tower in Wyoming shows how different types of rock weather at different rates ( Figure   ). The softer materials of the surrounding rocks were worn away. The resistant center of the volcano remains behind.
::怀俄明的恶魔塔展示了不同程度的岩石天气(图 ) 。 周围岩石的柔软材料被耗尽了。 火山的抵抗中心仍然落后。

Lesson Summary
::经验教训摘要

• Mechanical weathering breaks rocks into smaller pieces. Their composition does not change.
  ::机械风化把岩石碎成小块,其构成没有改变。

• Ice wedging and abrasion are two important processes of mechanical weathering.
  ::结冰和磨损是机械风化的两个重要过程。

• Chemical weathering breaks down rocks by forming new minerals. These minerals are stable at the Earth's surface.
  ::这些矿物质在地球表面很稳定

• Water, carbon dioxide, and oxygen are important agents of chemical weathering.
  ::水、二氧化碳和氧气是化学风化的重要制剂。

• Different types of rocks weather at different rates. More resistant types of rocks will remain longer.
  ::不同种类的岩石天气以不同的速度变化,更具抗力的岩石将持续更长的时间。

Lesson Review Questions
::经验回顾问题

Recall
::回顾

1. Name two types of mechanical weathering. Explain how each works to break apart rock.
   ::列出两种机械风化 解释一下如何打破岩石

1. What are three agents of chemical weathering? Give an example of each.
   ::三个化学气化剂是什么?请举一个例子。

Apply Concepts
::应用概念

3. How do acids form in the atmosphere? What increases the acidity of rainfall?
   ::酸如何在大气中形成?什么增加了降雨的酸性?

3. What are the effects of acid rain?
   ::酸雨有什么影响?

Think Critically
::仔细仔细思考

5. Describe what you think weathering would be like in an arid region. What would weathering be like in a tropical region?
   ::描述一下在干旱地区天气如何。在热带地区天气如何?

5. What type of surface weathers faster: a smooth surface or a jagged surface?
   ::哪些类型的地表天气速度更快:平滑的表面还是倾斜的表面?

Points to Consider
::需要考虑的要点

• What types of surfaces other than rock are affected by weathering?
  ::除岩石外,哪些表层受到气候变化的影响?

• What might the surface of the Earth look like if weathering did not occur?
  ::如果天气没有发生,地球表面会是什么样子?

• Do you think that you would be alive today if water did not dissolve elements?
  ::你认为如果水不溶解元素 你今天会活着吗?

• Would the same composition of rock weather the same way in three very different climates?
  ::在三种截然不同的气候下 同样的岩石天气构成会是一样的吗?