震级

On average, there are 18 killer quakes of magnitude 7.0 or greater around the world each year.

在世界范围内，平均每年有18次震级在7.0级或更高的地震。

Was the magnitude underplayed?

是否震级被缩小了？

Without considering surface covering layer, the surface earthquake dislocation and strain distribution near active fault were calculated under different conditions of magnitude, fault movement style and fault dip angle using 3-D finite element method. Based on above results, the safe distance of active fault to important project site was studied.

：在不考虑地表覆盖层的情况下，采用三维有限元方法计算了不同震级、不同断层活动方式以及不同断层倾角下断层上、下盘地表的地震位移及形变分布，通过设定的安全距离判定标准，研究了各种情况下工程场地距断层的安全距离。

Our result shows that the best double couple solution of this Mw5.2 event is 315°,64°and 19°for strike,dip and slip angles respectively,the second nodal plane solution is 214°,74°, and 152°.The focal depth is 25±2km,suggesting that this quake occurred in the lower crust which is much deeper than most continental earthquakes.This lower crust earthquake requires that the rock should be colder than expected.We proposed generation mechanism of this deep earthquake and its implications in rock strength and thermal state.

我们以此速度结构作为模型，利用中国国家地震台网5个台站的宽频带地震数据，采用CAP方法反演2003年8月16日赤峰地震震源机制解并初步确定震源深度：再利用IRIS 9个台站远震体波数据，通过对比高频(0.7～2.0Hz)理论地震图和观测记录的方法进一步精确确定震源深度并验证反演得到的机制解，得出此次地震矩震级为5.2，震源机制解为：节面I：315°/64°/19°，节面Ⅱ：216°/74°/152°，震源深度为25±2km，已深达下地壳。

With this velocity model and broadband records from 5 CDSN stations, we inverted focal mechanisms of Chifeng earthquake on August 16th, 2003 with the "Cut and Paste" method. Then we confirmed focal depth and the source mechanisms by comparing synthetic body waves at teleseismic distance with broadband records of 9 IRIS stations. Our result shows that the best double couple solution of this M w5.2 event is 315°, 64° and 19°for strike, dip and slip angles respectively, the second nodal plane solution is 216°,74°, and 152°. The focal depth is 25±2 km, suggesting that this quake occurred in the lower crust which is much deeper than most continental earthquakes.

我们以此速度结构作为模型，利用中国国家地震台网5个台站的宽频带地震数据，采用CAP方法反演2003年8月16日赤峰地震震源机制解并初步确定震源深度；再利用IRIS 9个台站远震体波数据，通过对比理论计算和观测记录的方法进一步精确确定震源深度并验证反演得到的机制解，得出此次地震矩震级为5.2，震源机制解为：节面I：315°/64°/19°，节面II：216°/74°/152°，震源深度为25±2 km，已深达下地壳。

The earthquake lacked the foreshocks that sometimes come with earthquakes of this magnitude.

地震缺少前震，它到来时的强度基本上和地震发生时所产生的震级是一样的。

More extensive logistic tree cited to describe an earthquake in graph of seismic division into districts tectonic geometry configuration, magnitude and the uncertainty with periodic recrudesce, among them diagnostic earthquake model includes: Sign of ザ grain screen is cast? of P of Wu of an ancient small-mouthed wine vessel of Jian of an ancient small-mouthed wine vessel of breasts of grain screen model and the float earthquake model that give magnitude of model of not fixed section.

在2008年地震区划图中引用了更为广泛的逻辑树来描述地震构造几何形态、地震震级和复发周期的不确定性，其中特征地震模型包括：单段破裂和多段破裂的特征地震模型，以及给定震级的浮动地震模型。

Magnitudes 6 and above are in red.

震级6及以上为红色。

Indonesia, a region that has been hit repeatedly by massive temblors,most recently a 7.6 earthquake in September that killed more than 1,000people.

印尼是一个反复遭受地震袭击的地方，最近的一次是在九月份，震级7.6，一千多人丧生。

The analyzing aboved is made from earthquake's space distributing, periodicity, migration phenomenon, repetition, strength, frequency, b value etc., according to data of earthquake station net in Shaanxi Province and microseisms station net watching results in Xi'an area. 3 group faults which are NEE, NW and EW direction control earthquake activities in Guanzhong area. Epicenter depth mostly is 5-25km and in shallow-focus earthquake. Earthquake in east area of Guanzhong was stronger and weaker in the West in history. Fen-Wei earthquake belt showed more activity. Microseisms and small seisms is main movement in recent earthquake, it has 8-10years' period of movement and show the trend that they are strong in the West but weaker in the East. And frequency and biggest magnitude of earthquake is supplement each other. In next years earthquake frequency will lessen but strength enhance, about M4. It presumes there is earthquake climax period in Guanzhong area in 2040 and M5-6 earthquake is happened at that time.

本文在对关中地区区域构造及重磁异常特征的分析基础上，根据陕西省地震台网监测资料及西安地区微地震台网监测成果，从地震的空间分布特征、周期性、迁移现象、重复性、强度、频度、b值分析等方面，对区域地震活动特征、关中地区地震活动规律进行了分析研究，关中地区地震活动主要受北东—北东东向、北西向、东西向三组方向的断裂控制，震源深度多为5—25公里，均属浅源地震，历史地震表现为东强西弱，东部的汾渭地震带表现出较强的地震活动性，近代地震活动主要以微震或小震为主，存在着8—10年的活动周期，近期表现出西强东弱的趋势，地震的频度与地震最大震级呈互补关系，未来的几年间，地震频度会有所减少，强度会增大，将有可能发生4级左右的地震，推测在2040年左右，关中地区将进入地震高潮期，届时将可能有5—6级左右的地震发生。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。