VOA慢速英语听力：GPS数据可以预测几小时前的地震 GPS Data Could Predict Earthquakes Hours Ahead.
Researchers say they have identified earth movement signals that could predict earthquakes up to two hours before they hit.
研究人员表示，他们已经发现了地球运动信号，可以预测地震发生前多达两小时。
The signals were recorded, or detected, by GPS collection devices. The devices were positioned in areas where major earthquakes had struck in the past.
这些信号是由GPS收集设备记录或探测到的。这些设备被放置在过去发生过大地震的地区。
Scientists noted, however, that the right equipment does not currently exist to use the data to predict earthquakes. But if the sensitivity of current GPS measuring devices can be improved, the researchers say a new earthquake warning system could be possible.
然而，科学家指出，目前并不存在适合利用这些数据进行地震预测的合适设备。但是，如果能够提高当前GPS测量设备的灵敏度，研究人员表示，一个新的地震预警系统可能成为可能。
Earthquakes are caused by movements, or slips, in existing faults under Earth’s surface, the U.S. Geological Survey (USGS) explains. A fault is a long break in rock attached to Earth’s crust. When tension builds up along a fault, energy waves are released and travel through the crust. This causes the ground to shake.
美国地质调查局（USGS）解释说，地震是由地球表面现有断层的运动或滑动引起的。断层是附着在地壳上的长断裂带。当沿断层积聚压力时，能量波被释放并穿过地壳。这导致地面震动。
Technology for predicting earthquakes currently remains very limited. But the USGS does have equipment that can pick up seismic data when an earthquake is just starting. The term seismic relates to earthquake activity.
目前，预测地震的技术仍然非常有限。但是，美国地质调查局（USGS）确实有设备可以在地震刚开始时捕捉到地震数据。地震一词与地震活动相关。
The USGS method makes it possible to warn people in areas where seismic activity is expected. But this method generally can only provide a warning several seconds before an earthquake hits. The USGS system is called ShakeAlert. It has already been deployed along the U.S. West Coast. That is where the majority of earthquakes happen in the country.
美国地质调查局的方法使得在预计发生地震活动的地区向人们发出警告成为可能。但这种方法通常只能在地震发生前几秒钟提供警告。美国地质调查局的系统被称为ShakeAlert。它已经在美国西海岸部署。那里是该国大多数地震发生的地区。
But the new detection method could produce warnings up to two hours before the damaging effects of an earthquake are felt. Such a system could save lives by giving people the chance to get out of buildings that might collapse in an earthquake.
然而，这种新的检测方法可能会在地震造成破坏性影响前提供多达两小时的预警。这样的系统可以通过给予人们逃离可能在地震中倒塌的建筑物的机会来挽救生命。
Two scientists from France’s National Research Institute for Sustainable Development carried out a study that described the latest results. The findings recently appeared in the publication Science.
来自法国国家可持续发展研究所的两名科学家进行了一项研究，描述了最新的结果。这些研究结果最近发表在《科学》杂志上。
For the study, researchers examined GPS data collected before and after past earthquake events around the world. The data was collected on 90 earthquakes measuring larger than 7 on the Richter scale. The study period covered the past 20 years.
为了进行这项研究，研究人员检查了世界各地过去地震事件发生前后收集的GPS数据。这些数据收集自90次里氏震级大于7级的地震。研究时间跨越了过去20年。
The team identified a pattern of fault movements as they examined the data collected from different areas. The movement signals were recorded within two hours of an earthquake striking. The researchers said the study demonstrates that faults generally begin to move about two hours before a large earthquake.
在检查来自不同地区的数据时，研究团队发现了一种断层运动的模式。这些运动信号在地震袭击后的两小时内被记录下来。研究人员表示，该研究证明断层在大地震前通常会开始运动约两小时。
Scientists had identified such signals before single earthquakes in the past. But until now, researchers were not able to link those signals to all seismic events.
科学家们在过去曾经识别出单个地震之前的这种信号。但直到现在，研究人员还没有能够将这些信号与所有地震事件联系起来。
While the data identified this pattern, the scientists said the instruments that could capture GPS data in real time do not currently exist.
尽管数据确认了这种模式，但科学家们表示目前并不存在能够实时捕捉GPS数据的仪器。
The National Research Institute for Sustainable Development issued a statement on the development. It said that in order to make predictions, researchers “would need to measure signals at least 10 times smaller than what we can presently do.”
国家可持续发展研究所对这一发现发表了一份声明。声明称，为了进行预测，研究人员“需要测量比我们目前能够测量到的信号至少小10倍的信号”。
Another way to possibly build a better earthquake prediction system would be to develop “dense measurement networks” that sit very close to faults. However, such an effort would require major technological progress, the institute said.
国家可持续发展研究所表示，可能构建一个更好的地震预测系统的另一种方法是开发“密集的测量网络”，它们位于断层非常近的地方。然而，这样的努力需要进行重大技术进步。
Quentin Bletery is a geophysicist at Côte d’Azur University in the city of Nice. Bletery worked together on the study with Jean-Mathieu Nocquet, another researcher at the university.
昆汀·布雷特里是尼斯市蓝色海岸大学的地球物理学家。他和另一名研究员让-马蒂尤·诺克特一起参与了这项研究。
Bletery told Science that the study found that no observable movement was identified in the first 46 hours leading up to an earthquake. But starting around two hours before an earthquake, the GPS signals recording movement started to increase.
布雷特里告诉《科学》杂志，研究发现地震前的头46小时内没有发现可观测的运动。但在地震前约两小时开始，记录运动的GPS信号开始增加。
To confirm its findings, the team compared that data to more than 100,000 random time periods recorded when no earthquakes were reported. That experiment found that similar patterns in non-earthquake areas happened just 0.03 percent of the time.
为了确认研究结果，团队将这些数据与记录没有地震发生的10万多个随机时间段进行了对比。该实验发现在非地震区域发生类似模式的概率只有0.03%。
“This tells us earthquakes are predictable in nature,” Bletery told Science.
布雷特里告诉《科学》杂志：“这告诉我们地震在本质上是可预测的。”
The scientists note that more research is needed to support their findings.
科学家指出需要进行更多的研究来支持他们的发现。
Much of the information used in the latest study, for example, depended heavily on data from GPS stations near major earthquake sites.
例如，最近的研究中使用的许多信息在很大程度上依赖于位于重大地震点附近的GPS站的数据。
I’m Bryan Lynn.
我是布赖恩·林恩。
Words in This Story
GPS – n. a system that follows the movements of something with an electronically-powered piece of equipment
pattern – n. a regular and repeated way in which something happens
resolution – n. a measure of the sharpness of an image or the fineness a device operates at
