Question

The goal of earthquake prediction is to give early enough warning. The U.S. Geological Survey conducts and supports research on the likelihood of future earthquakes. Scientists estimate earthquake probabilities in two ways: by studying the history of large earthquakes in a special area and the rate at which strain（拉力）accumulates（积累）in the rock.

Scientists study the past frequency of large earthquakes in order to determine the future likelihood of similar large shocks. For example scientists researched the large earthquakes in the San Francisco Bay region during the 75 years between 1836 and 1911. For the next 68 years, no earthquakes of magnitude (震级) 6 or large occurred in the region. Beginning with a magnitude 6 shock in 1979, the earthquakes in the region increased dramatically; between 1979 and 1989, there were four magnitude 6 or greater earthquakes, including a magnitude 7.1 earthquake. So scientists estimated that the probability of a magnitude 6.8 or larger earthquake occurring during the next 30 years in the region is about 67 percent.

Another way to predict earthquakes is to study how fast strain accumulates. When plate movements build the strain in rocks to a critical level, like pulling a rubber band too tight, the rocks will suddenly break and slip to a new position. Scientists measure how much strain accumulates along a fault (断层) each year, how much time has passed since the last earthquake, and how much strain was released in the last earthquake. This information is used to calculate the time required for the accumulating strain to build to the level that results in an earthquake. This simple model is so complicated that such detailed information about faults is rare. In the United States, only the San Andreas Fault System has adequate records for using this prediction method.

Scientific understanding of earthquakes is of vital importance to the Nation. As the population increases, expanding urban development and construction encroach (侵蚀) upon areas susceptible(易受影响的) to earthquakes. With a greater understanding of the causes and effects of earthquakes, we may be able to reduce damage and loss of life from this destruction.

1.What does the passage mainly talk about?

A．What an earthquake is like.

B．How to predict earthquakes.

C．Where earthquakes often happen.

D．When a fault is formed.

2.That scientists study the history of large earthquakes in certain areas is to ultimately_________.

A．do research on the past frequency of large earthquakes

B．estimate the magnitude of similar earthquakes

C．forecast the possibilities of similar earthquakes

D．judge the specific location of future earthquakes

3.Which is TRUE according to the passage?

A．There were four magnitude 6 earthquakes in the San Francisco Bay region between1979 and1989.

B．The accumulating strain of the fault to a certain level results in the earthquake.

C．About 68 years after 1911, no earthquakes occurred in the San Francisco Bay region.

D．The fast increasing population on the earth is the main cause of the earthquake.

4.What is the critical factor of forming a fault?

A．The material of rocks.

B．The existing time span of the rocks.

C．The plate movements around the rocks.

D．The amount of strain released in the last earthquake.

5.According to the passage, we can know that the San Andreas Fault System____.

A．has a greater understanding of the causes and effects of earthquakes

B．stores much more information about the history of large earthquakes

C．offers the potential for doing research on the faults where strain accumulates

D．illustrates specifically how rocks along a fault are formed

 

Answer 1

【答案】

1.B

2.C

3.B

4.C

5.C    

【解析】

试题分析：这篇文章讲的是如何预测地震，可以通过特殊地区大型地震来预测，也可以研究某个地方拉力的累积的情况知道地震的可能性。

1.主旨题：从第一段的句子：The goal of earthquake prediction is to give early enough warning.可知这篇文章讲的是如何预测地震。选B

2.细节题：从第二段的句子：Scientists study the past frequency of large earthquakes in order to determine the future likelihood of similar large shocks.可知科学家研究大地震是为了预测相似地震的可能性。选 C

3.细节题：从第三段的句子：This information is used to calculate the time required for the accumulating strain to build to the level that results in an earthquake.可知拉力累积到一定程度会导致地震，选B

4.细节题：从第三段的句子：When plate movements build the strain in rocks to a critical level, like pulling a rubber band too tight, the rocks will suddenly break and slip to a new position. 可知板块运动是形成断层的关键因素。选C

5.细节题：从第三段的句子：In the United States, only the San Andreas Fault System has adequate records for using this prediction method. 可知San Andreas Fault System对研究在拉力累积的地方形成断层提供可能。选C 。 

考点：考查科普类短文

点评：这篇文章讲的是如何预测地震，第一段指主题，第二段可以通过特殊地区大型地震来预测，第三段是研究某个地方拉力的累积的情况知道地震的可能性，结构非常清晰，便于学生找到答案，是这篇文章题型有细节题也有推理题，在答题中，应首先略读每题的信息，把几个选项含义理解透，抓住关键信息，要求学生在把握文章主旨的基础上，也要留意细节，对一些长难句的理解要准确。