>>>沪江汶川地震专题 

 

Introduction

简介

In order to reduce the risk of an earthquake and reduce and mitigate its effects, it is necessary to predict where and when a future, large earthquake may occur. For example, it would be important to know when such an earthquake will hit, where it will strike, and what the level of its destructiveness may be. Earthquake prediction at the present time is not an exact science, and forecastsof earthquake occurrences have not been very accurate. Presently predictions are given in statistical terms. For example, when a prediction is made that :here is a 90% chance that an earthquake will occur in the next 50 years", it does not mean that this earthquake cannot happen tomorrow or it may not be delayed by 50 years. Thus, present predictions are not within a reasonable time frame that can be of usefulness to planners, policy makers, and those in government that deal with public safety.

为了降低地震危险性（一定地区在未来一段时间内可能发生破坏性地震的危险程度）和减少地震带来的危害，那么预测一下未来是否有一场大地震，它将在何时何地 发生，这就显得很有必要。预测一场地震最重要的就是要知道地震发生的时间，地点及其破坏性。现在所谓的地震预测并不是一门精确科学，因此对于地震的预报也 没有那么精确。现在的地震预测都是用数字说话的，假如有预测说，未来50年里有90%的可能会发生地震，这并不意味着明天不会发生地震，也不是说50年后 才有可能发生地震。因此，现在的地震预测是无法给出一个合理的时间段的，而这不管是对于人们制定计划、作出决策还是对于负责公众安全的政府官员来说，都提 供不了多少帮助。

To understand earthquake prediction, three different time frames have been assigned by scientists: long term, intermediate and short-term predictions. Long term prediction involves a time frame of a decade or more and can only be general and with very limited usefulness for public safety. Intermediate term prediction would fall into a time span of a few weeks to a few years, and again it would not be of great practical usefulness. It is the short-term prediction, that is specific information on the time and location of an earthquake given within days, weeks, months - not years - that would be useful for any kind of public safety and evacuation.

要了解地震是如何预测出来的，我们必须先知道科学家提出的三个概念：长期，中期和短期。长期预测是指对10年之后的地震进行预测，但这只是大致的预测，对 确保公众安全起到的作用极为有限。中期预测的时间跨度可从数周到数年，但这也没有很大的实际作用。只有短期预测，这种在几天、几周或几个月里而并不是几年 预测到的地震的具体信息，才能在确保公众安全和及时撤离中真正发挥作用。

Several specific geophysical, geological, and chemical methods are presently used for earthquake prediction. To the list of geological and geophysical events and precursors we should add one more method that has been used with much success in China: that is the monitoring the behavior of animals before quakes.

目前我们一般用地球物理学、地质学和化学方法进行地震预测。在这里我还想再介绍一种方法，在中国，人们也曾多次用这种方法成功预报了地震，那就是通过观察动物的行为来监测地震。