首页
登录
职称英语
Since ancient times, the destructive effects of earthquakes on human lives a
Since ancient times, the destructive effects of earthquakes on human lives a
游客
2023-07-05
52
管理
问题
Since ancient times, the destructive effects of earthquakes on human lives and property have encouraged the search for reliable methods of earthquake prediction. This challenge remains and modern scientists continue to search for reliable methods to determine the time, place and intensity of individual quakes. One prediction technique involves an analysis of the recurrence(重现)rates of earthquakes as indicators of future activity. Earthquakes are concentrated in certain areas of the world which are subject to constant movements of earth’ s plates and it is in these areas that scientists focus their investigations.
This search for pre-earthquake phenomena has received particular attention. In contrast to the ancient Greeks and Romans, who relied on the crying of dogs as a warning sign, modern scientists have focused on physical evidence for a coming earthquake. Evidence of plate strain can be found by measuring relative movements, while chemical changes also offer signals for scientists.
Analysis of the changes in magnetic properties and conductivity(传导性)of rocks provides further data for prediction. The electrical and magnetic properties of crustal(地壳的)rocks are particularly sensitive to strain. The conductivity of crustal rock is determined by the degree to which the rock is soaked with fluid and the electrolytic properties of those fluids. Before large earthquakes, small fractures develop in rocks, which change the quantity of fluid present. These changes can be measured and provide useful data. However, similar changes in the fluid, bearing capacity of rock can occur as a result of other factors such as changes in the water table, and therefore this technique is not entirely reliable.
The ancient believe that the behavior of birds, cats and dogs provides evidence of inevitable earthquakes has recently been attended as a result of tests carried out in California. It has been shown that changes taking place in the metabolic(新陈代谢的)rates of these animals correlate with subsequent seismic activity. It is assumed that the animals are sensitive to the seismic waves which precede major quakes. In zones where earthquakes are known to occur, improved construction techniques can significantly reduce the effects of seismic waves. If more accurate information regarding the time and intensity were available, governments could take even more effective measures to reduce the impact on human life, if, however, an entirely accurate prediction technique became available, there would be significant social and political implications. [br] Which of the following is used by modern scientists to indicate a coming earthquake?
选项
A、The crying of dogs.
B、The conductivity of rocks.
C、The changes in the water table.
D、The quantity of fluid in earth.
答案
B
解析
细节题。短文第三段第一句指出Analysis of the changes in magneticproperties and conductivity of rocks provides further data for prediction.即对岩石的磁性和导电性变化的分析为地震预测提供了很多数据。故选项B正确。
转载请注明原文地址:https://tihaiku.com/zcyy/2810379.html
相关试题推荐
ImaginebeingaslaveinancientRome.Nowrememberbeingone.Thesecondta
Sinceancienttimes,thedestructiveeffectsofearthquakesonhumanlivesa
Sinceancienttimes,thedestructiveeffectsofearthquakesonhumanlivesa
Sinceancienttimes,thedestructiveeffectsofearthquakesonhumanlivesa
Isitpossibletopersuademankindtolivewithoutwar?Warisanancientin
Isitpossibletopersuademankindtolivewithoutwar?Warisanancientin
[originaltext]Inancienttimesthemostimportantexaminationswerespoken,
[originaltext]Inancienttimesthemostimportantexaminationswerespoken,
[originaltext]Inancienttimesthemostimportantexaminationswerespoken,
[originaltext]Inancienttimesthemostimportantexaminationswerespoken,
随机试题
[img]2018m5x/ct_epekm_epelist_0162_180525[/img][originaltext]Pleasepassmethe
AllsummerlongIhavebeendreamingofextravagantusesofwater.Idonot
会谈是指双方或多方为各自利益,就某些实质性问题交流情况、交换意见、达成协议等。会
弹性模量表示材料抵抗弹性变形的能力。()
A.1 B. C. D.
肺的通气/血流比值反映肺部气体交换的气泵与血泵的匹配情况。如果通气/血流比值增大
患者,男性,66岁,于1小时前突发胸闷,伴胸痛,位于心前区,且呈进行性加重,心悸
试述德育过程的基本规律。
既是抑菌剂,又是表面活性剂的是A.苯扎溴铵 B.液状石蜡 C.苯甲酸 D.
对于功能性低血糖病人,为减少低血糖发作,下述哪项饮食调整是不对的A、少食多餐
最新回复
(
0
)