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Everyone has heard of the San Andreas fault , whichconstantly threatens California and the West Coast with earthquakes. But howmany people know about the equally serious New Madrid fault in Missouri? Between December of 1811 and February of 1812, three majorearthquakes occurred, all centered around the town of New Madrid, Missouri, onthe Mississippi River. Property damage was severe. Buildings in the area werealmost destroyed. Whole forests fell at once, and huge cracks opened in theground, 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 runbackwards.Few people were killed in the New Marid earthquakes, probably simplybecause few people lived in the area in 1811; but the severity of theearthquakes are shown by the fact that the shock waves rang bells in churchtowers in Charleston, South Carolina, on the coast. Buildings shook in New YorkCity, and clocks wer stopped in Washington, D.C. Scientists now know thatAmerica s two major faults are essentially different. The San Andreas is ahorizontal boundary between two major land masses that are slowly moving inopposite directions. California earthquakes result when the movement of thesetwo masses suddenly lurches forward. The New Madrid fault, on the other hand, is a vertical fault; atsome points, possibly hundreds of millions of years ago, rock was pushed uptoward the surface, probably by volcanoes under the surface. Suddenly, thevolcanoes cooled and the rock collapsed, leaving huge cracks. Even now, therock continues to settle downwards, and sudden sinking motions trigger earthquakes in the region. The fault itself, a large crack in this layer ofrock, with dozens of other cracks that split off from it, extends fromnortheastArkansas through Missouri and into southern lllinois. Scientists who have studied the New Madrid fault say there have beennumerous smaller quakes in the area since 1811; these smaller quakes indicatethat larger ones are probably coming, but the scientists say have no method ofpredictingwhen a large earthquake will occur. 11. This passage is mainly about. A)the New Madrid fault in MissouriB)the San Andreasand the New Madrid faults C)the causes of faults D)currentscientific knowledge about faults 12. 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 13. 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 inMissouri C)California will become an island in future D)A big earthquake will occur to California soon 14. 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 15. As used in the first sentence of the fourth paragraph, the wordessentially means. A) greatlyC) basically B) extremelyD) necessarily Passage 3 11.B12.B13.A14.C15.C | 
