24. When The Earth Quakes. 24、地震时刻 1. On the night of August 17, 1959, at about 20 minutes before midnight, the ground in the vicinity of Yellowstone National Park began shaking violently. At the time there was a rumbling sound, something like a huge truck would make. Both the heaving of the ground and the noise were very frightening but lasted not quite 45 seconds. 1、1959年8月17日的晚上，大约午夜前20分钟，黄石国家公园附近大地开始猛烈摇动。同时，大地发出如同重型卡车发出的轰响。大地的升降和啸叫都令人非常害怕，但是一切不超过45秒。 2. What was even more frightening was the sound of huge boulders which began rolling down the steep mountain. In one part of the upper reaches of the Madison River, a whole mountain began shifting, then came crashing down to fill the deep valley and dam the great river with millions of tons rock and trees. 2、更令人害怕的是巨石开始从陡峭的山上滚下来的声音。在麦迪生河上游的一条支流处，一整座山开始移动，之后，它崩塌下来填满深深的山谷，上百万吨岩石和大树如坝般阻挡住大河。 3. A dozen or more campers along the river were buried deep beneath the great landslide. Others were able to climb to safety, some of them badly hurt, but were trapped by the slide. Finally these people were saved, many of them by helicopter. 3、十几个，或许更多沿河的露营者被深埋在大滑坡下。幸存的野营者开始爬向较安全的地方，其中一些人伤得很重，仍然不时陷入滑坡。最后这些人都获救了，其中多人得救于直升飞机。 4. This earthquake near Yellowstone Park was just one of nearly a million that happen every year all over the world. And as bad as this quake was, many have been worse. Earthquake experts say that the Yellowstone quake of 1959 was about as bad as the one which hit San Francisco in 1906.But the San Francisco quake caused more damage because it struck in a place where there were so many people living. In San Francisco 700 person lost their lives. An earthquake in Japan in 1923 took 160,000 lives. In china in 1920 an earthquake took 200,000 lives. It is easy to understand why earthquake are so feared. 4、在黄石公园附近发生的地震，仅仅是每年全世界发生的上百万次地震中的一次。若就地震灾害而论，有许多地震甚至更严重。地震专家说，1959年的黄石的地震，差不多相当于1906年发生在旧金山的地震。旧金山地震造成更多的破坏，他发生在人口密集地方。在旧金山约700人丧命。1923年发生在日本的地震夺走了16万人的生命。1920年一场大地震发生在中国，20万人死亡。因此，很容易理解人们为什么非常恐惧地震。 5. What causes these terrible shakes of the very ground on which we live? 5、是什么原因造成我们生活的这块土地发生可怕的摇动？ 6. To answer that question we must first understand some things about the earth itself. Forty miles deep in the earth is the edge of the outer crust of the earth, and there it is so hot that instead of hard rock there is material much like the hot lava that a volcano erupts. It is the earth s 40 mile deep crust with which we are concerned when we seek the cause of earthquake. The earth s crust is formed of many different layers of rocks. The layers of rocks are not laid evenly, as a bricklayer would build a wall. Instead, the earth s crust is made of rock layers that are often uneven and not perfectly balanced. Because of the great weight pressing down on them, these layers tend to fold downward at weak spots, and this finally causes an actual break in the crust. When this break occurs, or when the sides of an old break slip, the earth quakes, or shakes, while the crust is settling into a new position.