Plate tectonic theory 地表板塊構造論

Plate tectonic theory 地表板塊構造論

Welcome to Sunday Science! Every Sunday, we're going to guide you through some cool experiments that you can do at home. It's a good idea for you to keep a record of what you do in a Science Journal. That way you can record what you learn, compare results and maybe use them to design new experiments! Have a look at the Science Journal box for some ideas to get you started. Remember to always ask a grown-up's permission before trying out an experiment.

歡迎閱讀《週日科學版》！我們每週日都要為你介紹可以在家中進行的有趣科學實驗。你可以在《科學日誌》中 記錄自己做了哪些活動，這樣就可以將所學的紀錄下來，比較這些結果，也許還可以利用它們來設計新的實驗！先看一下《科學日誌》的點子再開始吧。展開實驗之 前，記得要獲得大人許可喔！

Sunday, Jan 13, 2008,Page 14

照片︰CATHERINE THOMAS PHOTO: CATHERINE THOMAS, TAIPEI TIMES

Taiwan has lots of earthquakes. Do you know why? This week we're going to look at plate tectonic theory. This experiment can be very messy, so make sure you do it over a bowl or a sink.

What you will need:

A box of eggs

Toothpaste

The chamber part of a syringe

A bowl

A large world map

Tracing paper (optional)

Tissues (optional)

▲ Ask a grown-up to help you hard-boil some eggs. Gently tap the pointed end of one of the eggs when it's still raw so that you break a small part of the shell.

▲ As the eggs boil, observe what happens to the damaged egg.

▲ Let the eggs cool. Put the damaged egg to one side.

▲ Very carefully tap an egg on a hard surface so that you get some cracks in the shell. Be careful, you don't want too many, one or two is fine!

▲ The surface of the egg is now a little like the surface of the earth, with separate plates. Try gently moving the plates around by pressing gently on the egg's surface. Move them so that they slide past each other

and move away from each other. How do the plates interact?

▲ Choose a crack and push on either side so that the plates move toward each other and change shape. What does the result remind you of?

▲ Take the syringe chamber and put in a few squeezes of toothpaste.

▲ Take the damaged egg. It should have some cracks along the surface. Hold the egg so that you can see a nice long crack.

▲ Clear part of the shell away at the point of the egg so that you can see the white inside.

▲ Insert the nozzle into the egg white. Then slowly start pumping the toothpaste into the egg. Observe what happens.(CATHERINE THOMAS, STAFF WRITER)

台灣常常有地震，你知道為什麼嗎？這週我們要來探索「地表板塊構造論」，這個實驗會弄得很髒，所以你最好在一個碗裡或水槽中進行。

所需材料︰

一盒雞蛋

牙膏

針筒的筒身

一個碗

一大張世界地圖

描圖紙（非必要）

紙巾（非必要）

▲ 請大人幫你把幾顆蛋連殼煮到全熟；在蛋還是生的時候，先輕敲其中一顆的尖頭端，讓蛋殼破裂一小塊。

▲ 蛋煮熟後，觀察那顆破損的雞蛋有什麼變化。

▲ 把蛋放涼，取出破損的蛋，放到一旁。

▲ 在堅硬的表面上非常小心地輕敲一顆蛋，讓蛋殼產生裂縫；注意，你不需要敲裂太多，一、兩處就夠了！

▲ 現在，雞蛋的表面有點接近地球表面，有分散的板塊。試著輕輕地在雞蛋表面施加壓力，使板塊和緩地在周圍移動，從彼此間滑過又移開，這些板塊如何相互影響？

▲ 選一個裂縫從其中一側施力，這樣板塊會朝彼此移動，進而改變形狀，結果會讓你想到什麼？

▲ 在針筒中擠入一些牙膏。

▲ 取來受損的雞蛋，那上面應該有一些裂縫，托住這顆蛋以便觀察上面完整的長條裂縫。

▲ 將雞蛋尖頭端部份蛋殼剝掉，你就可以看到裡面的蛋白。

▲ 將針嘴插入蛋白，然後慢慢地將牙膏擠壓入蛋中，觀察後續情況。 （翻譯：袁星塵）

WHAT'S THE SCIENCE? 科學原理 The earth is made up of a very hot core. The inside of the core is solid and the outside liquid. The next layer is called the mantle - it has upper and lower parts. One part of the upper mantle is called the asthenosphere. This part is solid, but can "flow" very slowly, just like toothpaste. On top of the asthenosphere is the lithosphere. The tectonic plates are part of the lithosphere. The plates are made up of continental crust (which is very thick) and oceanic crust (which is much thinner). Most plates are a mixture of both oceanic and continental crust. The plates move on top of the asthenosphere at varying speeds and in different directions. The plates either come together (converge), move apart (diverge) or slide horizontally past each other (creating a fault). Sometimes when two plates converge, one goes under the other, just like on the egg. The movements of the plates are responsible for earthquakes, the creation of mountains and islands and many other things. The damaged egg with the toothpaste shows what happens under the ocean when plates diverge. Magma rises up and flows out of the cracks. This is called ocean floor spreading. The pressure that you apply through pumping in the toothpaste acts like the pressure of the heat in the earth's core. Scientists believe that it is this heat that causes the earth's plates to move. The plates move only a few centimeters each year. This is about the same speed as your fingernails grow at. 地球是由極度高溫的核心所組成，地核內部是固態，而外部是液態；第二層稱作地函─分成上下兩部份，上層地函有一部份稱作「軟流圈」， 軟流圈是固態的，但是能夠非常緩慢地「流動」，就像牙膏一樣；軟流圈上層是岩石圈，板塊是岩石圈的一部分。 板塊由陸殼（非常厚）和洋底殼（厚度薄很多）構成，多數板塊是由陸殼和洋底殼結合而成的，板塊在軟流圈上移動，速度和方向都各不相同； 板塊會匯聚（聚合）、散開（張裂）或相互水平錯動（形成斷層）；有時，兩板塊匯聚時，一塊可能會潛入另一塊下方， 就像雞蛋實驗一樣。這些板塊的運動解釋了地震、山脈和島嶼以及其他許多現象形成的原因。那顆受損的雞蛋擠入牙膏後， 顯示板塊張裂時海洋下的活動，岩漿上衝湧出裂縫的現象稱為「海底擴張」； 你擠入牙膏時所施加的壓力就類似地核裡高熱的壓力，科學家認為就是地核的熱度導致板塊移動， 板塊每年僅會移動幾公分，約等同於指甲生長的速度。

VOCABULARY 今日單字 1. plate tectonics theory n. phr. 地表板塊構造論 (di4 biao2 ban3 kuai4 gou4 zao4 lun4) 2. hard-boil v. phr. 煮全熟 (zhu3 quan2 shou2) 3. damaged adj. 受損的 (shou4 sun3 de5) 4. crack n. 裂縫 (lie4 feng4) 5. interact v.t. 互相影響 (hu4 xiang1 ying2 xiang3) 6. nozzle n. 嘴管 (zui2 guan3) 7. continent n. 大陸 (da4 lu4) 8. core n. 核心 (he2 xin1) 9. crust n. 地殼 (di4 ke2) 10. oceanic adj. 海洋的 (hai3 yang2 de5) 11. horizontally adj. 水平的 (shui3 ping2 de5) 12. fault n. 斷層 (duan4 ceng2) 13. magma n. 岩漿 (yan2 jiang1)