他们的房子修建得很坚固，经受住了主震。
Their house, which was solidly built, resisted the main shock.
主震后又有无数次余震，最大余震超过7级。
Numerous aftershocks were recorded with one having a magnitude greater than 7.
余震可以在主震发生后的一个月或者几天之内发生。
It can happen with a month, or within days, from the main shock.
通常余震比主震弱，但是，在主震中受损的建筑往往因余震倒塌。
Aftershocks are generally weaker than the main quake, but buildings that have already been damaged are prone to collapse in an aftershock.
这些余震虽然一般较主震为弱，但也足以造成进一步损害，并使建筑物更脆弱。
These secondary earthquakes are usually less violent than the main quake, but they can be strong enough to cause additional damage and weaken buildings.
信号震和主震沿同一构造体系活动；
Signal earthquake and the major earthquake seem to be controlled by the same structural system.
地震序列类型为前震—主震—余震型；
本文讨论了地震序列中前震、主震和余震的烈度。
This paper discusses the intensity of the earthquake sequences, which include the foreshock, main shock and aftershock.
已经受损的建筑物会因主震后的余震而进一步损坏。
Damaged buildings may be destroyed by aftershocks following the main quake.
该结果对主震和最大余震的预测具有一定的参考价值。
This result has a certain reference value for forecasting of main shock and the maximum aftershock.
与唐山主震震源机制解结果和野外宏观考察结果基本一致。
It is essentially consistent with the results from the earthquake source mechanism solution and the results of field macroscopic observations of the main Tangshan earthquake.
大震后有60%的强余震与主震发震时刻的倾斜固体潮背景相同。
The background of tilt earth tide of 60% strong aftershocks after large earthquakes is similar to that of main shocks at the original times.
因此认为，最大余震可能是由主震引起的库仑破裂应力变化触发的。
Therefore, the largest aftershock was probably triggered by the Coulomb failure stress change.
北北东—南南西向分布的余震发生在主震的断层面上（或其附近）；
The NNE-SSW distributed aftershocks occurred on, or near, the fault plane of the main shock;
主震后，由于释放了绝大部分应力，余震序列则表现为低应力破裂过程。
After the main shock, most of the stresses have been released, so the aftershock sequences show a rupture process of lower stresses.
主震后不到一个小时的时间里，又发生了两次余震，一次5.0级，一次5.2级。
Within an hour after the main shock, two aftershocks, one of magnitude 5.0 and the other 5.2, occurred.
汶川地震的主震发生在具有右旋性质的仰冲型断层带上，震源深度为15公里左右。
The main shock occurred on the dextral obduction-type fault zone and the hypocenter depth was about 15km .
一般来说余震代表发生主震的断层的微小重调。余震的发生频率随着时间慢慢减小。
As a general rule, aftershocks represent minor readjustments along the portion of a fault that slipped at the time of the main shock.
由此推测，主震的错动面为北西西走向，可能是高倾角的左旋平移断层的滑动结果。
From this, it has been inferred that the strike of the dislocating fault plane of the main shock is NWW. It seems to be a left lateral horizontal slip fault with high dipping Angle.
此外，强震的余震多为中小地震，大量中小余震可为主震发震机理研究提供重要信息。
Moreover, most aftershocks of strong earthquake are small and moderate events, which provide important information on focal mechanism of mainshock.
余震发生在主震的断层面上(或其附近)，是由主震断层面附近介质的应力调整造成的。
The aftershocks were distributed on (or near) the fault plane and were triggered by the stress redistribution in the medium in the nearby region of the fault plane.
本次4.9级地震作出的震源机制解显示为走滑型，与1969年主震的情况较为类似。
The focal mechanism of the M4.9 earthquake shows that it belongs to strike slip type that is similar to the M6.4 earthquake in 1969.
本文研究了主震与若干余震的震源机制解，并应用零矢量方法确定了地震破裂面的走向。
In this paper the focal mechanism of the major shock and several aftershocks has been studied and the strike of seismic fracture has been also determined by means of null vector data.
坝体-坝基动力相互作用在地震过程中的不同阶段表现有所不同，主震阶段的相互作用显著。
In different phases of the earthquake process, effects of the dynamic dam-foundation interaction are different. The interaction is rather prominent in the main shock phase.
YUS台附近的地壳应力在主震后得到了增强，随着余震活动导致的应力释放，后期应力减小。
The stress at station YUS increased after the main-shock, and with the stress release caused by the aftershocks, the stress reduced in the late stage.
用姚安地震序列前震、主震和余震的78个震源机制解，分析了序列震源断层和震源应力场特征。
We use 78 focal mechanisms of the fore shocks, main-shock and after shocks of the Yao 'an earthquake sequence to analyze the characteristics of focal fault and stress field.
结果表明，前震的一组节面比较集中且与主震断层面大体一致，其主压应力轴也表现出相对的集中。
The results show that the group of nodal planes of pre shocks puts together comparably and identical with the fault of main shock, so do their P axes.
挤压型逆冲断层地震在主震之后，应力传播和释放过程比较缓慢，可能导致余震强度较大，持续时间较长。
Compressive faults occurred after principal earthquake with slow variation in propagation and release of stress wave, this might lead to higher after shock intensity and longer duration.
我们所观测到的世界上地震发生后强度最大的余震通常要比主震小一级，一般是在几个月内发生，但也可能是在几年后。
The largest aftershocks of an earthquake over the years around the world we've observed tend to be about one magnitude unit less than the main shock, more likely within months, but it could be years.
我们所观测到的世界上地震发生后强度最大的余震通常要比主震小一级，一般是在几个月内发生，但也可能是在几年后。
The largest aftershocks of an earthquake over the years around the world we've observed tend to be about one magnitude unit less than the main shock, more likely within months, but it could be years.
应用推荐