Question

    Compared to other causes of natural disasters, volcanoes offer clues only when they are about to erupt. Now, however, developments in monitoring systems have allowed scientists to develop sensors to detect and forecast eruptions more accurately.

University of Cambridge volcanologist Marie Edmonds says that scientists are now able to use very accurate sensors to monitor the gases volcanoes give out, which can give clues on the location of the magma. The sensors help with prediction because different gases are released at different stages of an eruption. When magma rises, pressure is released along with gases. Carbon dioxide is released early on and then, as the magma goes higher, Sulphur dioxide is released. The ratio of the two gases is used to detect the location of magma relative to the surface, telling researchers the coming of the eruption.

Edmonds is connected to an international group known as the Deep Carbon Observatory that has worked to put new gas sensors on fifteen of the most active and dangerous volcanoes to improve the forecasting of various types of eruptions. The gas sensors continually measure water vapor, sulphur dioxide, and carbon dioxide. They are placed inside large boxes with surface antennae and buried underground. Advances in electronics have increased their accuracy and lowered their cost, allowing more of them to be used worldwide.

Putting these sensors atop active volcanoes is dangerous. Scientists wear reflective suits that protect against heat, plus gas masks for protection from dangerous gases. They sometimes hike long distances in remote areas to reach a site. However, according to Edmonds, the work they do to save people’s lives makes a dangerous job worth it. She enjoys doing something that helps people.

Edmonds’ team has also attached sensors to a certain plane to measure gases released from a Papua New Guinea volcano for a short time, a technique developed to gather “snapshots” of the activity. These snapshots help researchers to better understand activities that lead to eruptions.

1.How do sensors detect and predict volcanic eruptions?

A.By sending warnings to researchers. B.By testing different gases released.

C.By measuring the heat underground. D.By studying the surrounding gases.

2.What do we know about the gas sensors?

A.They should be attached to the magma. B.They are available around the world.

C.They become more accurate and expensive. D.They can check various types of eruptions.

3.Why is it risky to place sensors atop active volcanoes?

A.Active volcanoes may erupt at any time. B.It’s hard to find the top of volcanoes.

C.Scientists are short of enough suits and masks. D.There is heat and dangerous gases

4.What can the snapshots do?

A.Predict volcanic eruptions earlier. B.Attract people’s attention to volcanoes.

C.Collect more information for researchers D.Avoid the danger of the researchers’ work.

Answer

1.B

2.B

3.D

4.C

【解析】

这是一篇说明文。与其他自然灾害的原因相比，火山只有在即将爆发时才会提供线索。然而现在，随着监测系统的发展，科学家们已经能够开发传感器来更准确地探测和预测火山爆发。气体传感器通过检测释放出的不同气体来检测和预测火山爆发。同时剑桥大学火山专家Marie Edmonds与国际组织联系，将这种传感器安装在了15座最活跃、最危险的火山上，文章还介绍了Edmonds对火山预测所做的一些其他努力。

1.

细节理解题。根据第二段中The sensors help with prediction because different gases are released at different stages of an eruption. When magma rises, pressure is released along with gases. Carbon dioxide is released early on and then, as the magma goes higher, Sulphur dioxide is released. The ratio of the two gases is used to detect the location of magma relative to the surface, telling researchers the coming of the eruption.可知传感器有助于预测，因为不同的气体会在火山喷发的不同阶段释放出来。当岩浆上升时，压力和气体一起释放出来。二氧化碳在早期被释放出来，然后随着岩浆上升，二氧化硫被释放出来。这两种气体的比例可以用来探测岩浆相对于地表的位置，从而告诉研究人员火山爆发的来临。由此可知，传感器通过检测释放出的不同气体来发现和预测火山爆发。故选B。

2.

推理判断题。根据第三段中Edmonds is connected to an international group known as the Deep Carbon Observatory that has worked to put new gas sensors on fifteen of the most active and dangerous volcanoes to improve the forecasting of various types of eruptions.可知Edmonds与一个名为“Deep Carbon Observatory”的国际组织有联系，该组织致力于在15座最活跃、最危险的火山上安装新的气体传感器，以提高对各种类型喷发的预测。由此可推知，世界各地都有气体传感器。故选B。

3.

细节理解题。根据倒数第二段中Putting these sensors atop active volcanoes is dangerous. Scientists wear reflective suits that protect against heat, plus gas masks for protection from dangerous gases.可知把这些传感器放在活火山上是危险的。科学家们穿着防热的反射服，外加防毒面具来保护自己免受危险气体的伤害。由此可知，活火山上的热量和危险气体，使得在活火山上放置传感器有风险。故选D。

4.

细节理解题。根据最后一段Edmonds’ team has also attached sensors to a certain plane to measure gases released from a Papua New Guinea volcano for a short time, a technique developed to gather “snapshots” of the activity. These snapshots help researchers to better understand activities that lead to eruptions.可知Edmonds的团队还在一架飞机上安装了传感器，用来测量巴布亚新几内亚一座火山短期内释放的气体，这项技术是用来收集火山活动的“快照”。这些快照有助于研究人员更好地了解导致火山爆发的活动。由此可知，快照可以为研究人员收集更多关于火山活动的信息。故选C。