Everyone has heard of the San Andreas fault , which constantly threatens California and the West Coast with earthquakes. But how many people know about the equally serious New Madrid fault in Missouri? Between December of 1811 and February of 1812, three major earthquakes occurred, all centered around the town of New Madrid, Missouri, on the Mississippi River. Property damage was severe. Buildings in the area were almost destroyed. Whole forests fell at once, and huge cracks opened in the ground, allowing smell of sulfurto filter upward. The Mississippi River itself completely changed character, developing sudden rapids and whirlpools. Several times it changed its course, and once, according to some observers, it actually appeared to run backwards.Few people were killed in the New Marid earthquakes, probably simply because few people lived in the area in 1811; but the severity of the earthquakes are shown by the fact that the shock waves rang bells in church towers in Charleston, South Carolina, on the coast. Buildings shook in New York City, and clocks wer stopped in Washington, D.C. Scientists now know that America s two major faults are essentially different. The San Andreas is a horizontal boundary between two major land masses that are slowly moving in opposite directions. California earthquakes result when the movement of these two masses suddenly lurches forward. The New Madrid fault, on the other hand, is a vertical fault; at some points, possibly hundreds of millions of years ago, rock was pushed up toward the surface, probably by volcanoes under the surface. Suddenly, the volcanoes cooled and the rock collapsed, leaving huge cracks. Even now, the rock continues to settle downwards, and sudden sinking motions trigger earthquakes in the region. The fault itself, a large crack in this layer of rock, with dozens of other cracks that split off from it, extends from northeastArkansas through Missouri and into southern lllinois. Scientists who have studied the New Madrid fault say there have been numerous smaller quakes in the area since 1811; these smaller quakes indicate that larger ones are probably coming, but the scientists say have no method of predictingwhen a large earthquake will occur. 1. This passage is mainly about . A)the New Madrid fault in Missouri B)the San Andreas and the New Madrid faults C)the causes of faults D)current scientific knowledge about faults 2. The New Madrid fault is . A) a horizontal fault B) a vertical fault C) a more serious fault than the San Andreas fault D) responsible for forming the Mississippi River 3. We may conclude from the passage that . A) it is probably as dangerous to live in Missouri as in California B) the New Madrid fault will eventually develop a mountain range in Missouri C) California will become an island in future D) A big earthquake will occur to California soon 4. This passage implies that . A) horizontal faults are more dangerous than vertical faults. B) Vertical faults are more dangerous than horizontal faults C) Earthquakes occur only around fault areas D) California will break into pieces by an eventual earthquake 5. As used in the first sentence of the fourth paragraph, the word essentially means . A) greatly C) basically B) extremely D) necessarily Passage 3 1.B 2.B 3.A 4.C 5.C
雅思词汇:那些与old相关的地道习语
雅思词汇记忆其实也不难:拆字法
两种雅思词汇记忆方法介绍
雅思考试分类词汇:有关教育常用词汇
雅思考试分类词汇:有关会议的词汇
雅思考试分类词汇:有关公司员工职务词汇
雅思词汇:词根背单词“-rupt-”
实用雅思分类词汇:饮食
雅思考试分类词汇:有关国外节日词汇
雅思常用分类词汇:艺术-1
雅思考试分类词汇:有关家畜的词汇
雅思词汇:英语单词记忆法之拆字法
雅思分类词汇:亲属称谓-6
快速提高雅思词汇量的方法
雅思词汇记忆其实也不难:新构词法
雅思词汇:词根背单词“-voc-”
雅思词汇:英语单词记忆法之同构法
雅思听力场景高频词:银行场景
雅思词汇:虚弱无力的和穿上
雅思词汇:专家总结背诵雅思单词的方法
雅思词汇:英语单词记忆法之异构法
雅思词汇:记单词的20种方法
雅思常用分类词汇:船舶-2
雅思考试分类词汇:有关度量衡词汇
雅思词汇:英语单词记忆法之对比法
词根法巧记雅思词汇:“corp-/corpor-”
雅思词汇:词根背单词“-viv-/-vit-/-vig-”
雅思词汇记忆其实也不难:音像法
雅思常用分类词汇:船舶-1
雅思词汇:词根背单词“-vac-/-van-/-uoid-”
| 不限 |
| 英语教案 |
| 英语课件 |
| 英语试题 |
| 不限 |
| 不限 |
| 上册 |
| 下册 |
| 不限 |