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1.
地震活动图像特征与强震危险区经验性预测依据的初步研究 总被引：1，自引：0，他引：1
在研究近期（10年）强震危险性判定和总结四川地区1972--2002年强震预测经验的基础上，清理了中国大陆1920--2002年47次浅源大震事件前地震活动图像特征（M≥4．7），提炼出10个方面12项经验性预测依据：主体活动区、多发时段、关联序列、大陆及地区地震异常图像、地区（带）-地段（震源区）地震增强图像（含信号震、诱发地震、地震条带）、相关地震、窗口地震、复发间隔、大陆及地区缺震、地段缺震与地段强震一缺震转折等。它们在47次震例中的综合出现率≥0．58（即依据比7／12以上）占42例；≥0．66（即8／12以上）占34例。因此，强震（M≥4．7）活动图像经验性预测依据可以作为预测有较大可能发生大地震危险区的依据之一。 相似文献
2.
中等地震活动增强作为强震标志的研究 总被引：7，自引：0，他引：7
通过对(1990~1996年)发生在我国大陆及边境地区24次6级以上地震的分析研究表明,80%的强震主震前在震源区及附近有中等地震活动增强的过程。异常表现出共同的基本特征,即长期平静→增强活动→震前平静→发震。震前平静至发震大约经历几个月到2年时间(平均10个月左右),可以作为中短期地震预报判据。用岩石蠕变声发射实验来解释这一现象,可把中等地震活动增强看作是稳态蠕变阶段后期发生的广义前震。 相似文献
3.
华北成组强震孕育过程及预测研究 总被引：1，自引：0，他引：1
利用华北丰富的历史地震资料, 通过研究地震与块体活动的联系, 揭示了地震高潮期的形成过程。 认为地震高潮期成组强震的孕育与区域块体的运动方式相联系。 一个地震活动期可分为二个阶段, 在前期块体边界的运动是很不平衡的, 各组地震主要是由于各局部范围若干闭锁段破裂和破裂间相互作用的结果, 当沿块体边界的破裂发展到一定程度时, 这些边界所围的地块就会进入以整体运动为主的阶段, 这时块体边界的运动具有一定程度的同步性, 加之闭锁段破裂后不再重新闭锁, 从而导致块体边界闭锁段由弱到强渐进式的破裂过程, 直至一组强闭锁段完成破裂, 形成地震活动高潮。 这是成组强震形成的根本原因, 另外强震间的诱发作用也是强震成组发生的重要原因。 最后概述了如何利用以上模式预测地震高潮期的时间、 强度和主体活动场所。 相似文献
4.
强震前中短期地震活动异常动态图像的表示方法及其预测意义 总被引：4，自引：0，他引：4
提出了二个描述中强震发生前中短期阶段地震活动异常时空演经图像的参量σＮ、σＥ。分别将其用于华北地区、新疆地震区及南北地震带,并对其预报效能进行检验,对其异常的空间分布图像与强震发生地震进行了分析,结果表明,该二参量能较好地瓜倾吐夺前中短期阶段孕震区及其周围地区地震活动的异常平静及丛集的现象。二参量异常的时空分布图像上示出在中强震发生前３个月至１年在震中周围地区有明显的异常分布,且随着时间逼近发震时 相似文献
5.
强震发生前震源及其周围地区可能会出现前震活动, 这种前震活动可以分为二种: 一种为连续型, 即前震的频度或震级随时间渐渐增大, 直至主震发生; 另一种为不连续型, 前震的频度和震级先增大后减小, 然后发震。 这种现象不但在破裂声发射试验中观测到, 也在中国大陆地区多次强震前被观测到。 文中基于细胞自动机模型, 引入时间-状态依从摩擦本构关系, 即把自组织非线性系统的普适特征与真实断层摩擦的具体特征结合起来, 研究了强震前短期前兆地震活动的时间演化过程的机理。 文中研究了模型中各参数对模拟事件时间过程的影响, 结果表明, 静摩擦强度在断层上的分布, 或是说静摩擦系数的离散程度直接影响强震前地震活动时间演化过程。 相似文献
6.
According to geological tectonics and seismic activites this paper devided North China (30°–45°N, 105°–130°E) into four areas.
We analyzed the North China earthquake catalogue from 1970 to 1986 (from 1965 to 1986 for Huabei, the North China, plain region)
and identified forty-two bursts of aftershock. Seven of them occurred in aftershock regions of strong earthquakes and seventeen
of them in the seismic swarm regions. The relation between strong earthquakes with the remaining eighteen bursts of aftershocks
has been studied and tested statistically in this paper. The result of statistical testing show that the random probabilityp of coincidence of bursts of aftershock with subsequent strong earthquakes is less than six percent. By Xu’sR scoring method the efficacy of predicting strong earthquake from bursts of aftershock is estimated greater than 39 percent.
Following the method proposed in the paper we analyzed the earthquake catalogue of China from 1987 to June, 1988. The results
show that there was only one burst of aftershock occurred on Jan. 6, 1988 withM=3.6 in Xiuyan of Northeast China. It implicates that a potential earthquake withM
S⩽5 might occur in one year afterwards in the region of Northeast China. Actually on Feb. 25, 1988 an earthquake withM
S=5.3 occurred in Zhangwu of Northeast China. Another example is Datong-Yanggao shock on October 18, 1989 which is a burst
of aftershock. Three hours after an expected shock withM =6.1 took place in the same area. Two examples above have been tested in practical prediction and this shows that bursts
of aftershocks are significant in predicting strong earthquakes.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,13, 273–280, 1991.
Part of earthquake catalogue is from Jinbiao Chen, Peiyan Chen and Quanlin Li. 相似文献
7.
8.
Cheng Kueihsiang 《中国地震研究》2003,17(1):85-96
The data of earthquakes with M≥3.0 during the 7 years from September 21, 1993 to September 20, 2000 recorded by the Taiwan Central Weather Bureau (CWB) show that there were 6 types of clear characteristics of seismicity during the Chi-Chi strong earthquake swarm of September 21. These 6 types of characteristics are (1) foreshock types, (2) seismic gaps, (3) seismic bands, (4) clustering activity of foreshocks and signal shock, (5) quiescence before the main shock and (6) secondary aftershocks in the aftershock sequence. Using the procedures for analyzing the yearly strong earthquake tendency, further tracing based on the earthquake sequence characteristics, and taking the Chi-Chi earthquake sequence as an example, tracing analysis of the earthquake tendency was attempted using the shorter time range of monthly rather than in a yearly time scale. An attempt was made to establish the procedures for tracing analysis of shallow-focus earthquakes in the seismic belt of western Taiwan. It is hoped that this can provide an analystical method for approaching the short-imminent time scale of seismometry-based earthquake forecasting. 相似文献
9.
1997年伽师强震群及预报概况 总被引：1，自引：1，他引：1
１９９７年１月２１日以来，新疆伽师地区发生了强震群活动，至４月１６日共发生７次６级地震，新疆维吾尔自治区地震局追踪分析了强震群序列和前兆资料，对其中３次６级，３次５级地震公开向社会作出临震预报，取得了明显的社会减灾实效。 相似文献
10.
11.
The reason for the failure to forecast the Wenchuan M_S8.0 earthquake is under study, based on the systematically collection of the seismicity anomalies and their analysis results from annual earthquake tendency forecasts between the 2001 Western Kunlun Mountains Pass M_S8.1 earthquake and the 2008 Wenchuan M_S8.0 earthquake. The results show that the earthquake tendency estimation of Chinese Mainland is for strong earthquakes to occur in the active stage, and that there is still potential for the occurrence of a M_S8.0 large earthquake in Chinese Mainland after the 2001 Western Kunlun Mountains Pass earthquake. However the phenomena that many large earthquakes occurred around Chinese Mainland, and the 6-year long quietude of M_S7.0 earthquake and an obvious quietude of M_S5.0 and M_S6.0 earthquakes during 2002～2007 led to the distinctly lower forecast estimation of earthquake tendency in Chinese Mainland after 2006. The middle part in the north-south seismic belt has been designated a seismic risk area of strong earthquake in recent years, but, the estimation of the risk degree in Southwestern China is insufficient after the Ning’er M_S6.4 earthquake in Yunnan in 2007. There are no records of earthquakes with M_S≥7.0 in the Longmenshan fault, which is one of reasons that this fault was not considered a seismic risk area of strong earthquakes in recent years. 相似文献
12.
新疆两次强震前后地震视应力变化 总被引：2，自引：0，他引：2
选取了喀什数字地震台记录的喀什及周边地区地震的宽频带波形资料,分析处理了2001～2005年Ms 3.5以上地震164次,通过数字地震波谱计算了标量地震矩和地震辐射能量,从而进行了视应力的计算.给出了巴楚-伽师Ms 6.8和乌什Ms 6.3强震前后视应力的时序变化情况,发现其视应力均表现出震前低应力阶段-主震前的逐渐上升-震后逐渐恢复的动态变化过程,即地震的孕震-发震-震后调整的阶段性变化特征.这一结果可为喀什及周边地区今后进行地震预测预报研究提供参考依据,对该区开展数字地震方面的研究也有所帮助. 相似文献
13.
根据统计分布与信息熵理论，定义了震级信息熵Hm和地震间隔时间信息熵Ht，并推导了它们的计算公式。通过时空扫描和计算，发现强震前1～3年Hm和Ht出现低值异常，与地震有较好的对应关系，可以作为一组中期或中短期预测指标。 相似文献
14.
The definition and abnormality discriminatory criteria of earthquake flow function are introduced in this paper based on the algorithm of Space Increased Probability (SIP). Nine earthquake flow functions were defined by the method. The retrospect test that applied the SIP algorithm with the nonlinear earthquake flow function to 7 earthquakes, which occurred from 1975 to 1989 in Eastern China, with a magnitude of 6 or greater depicted that 6 of the 7 strong earthquakes (86%) were located in the SIP areas, and the SIP covers about 32% of the total research time-space domain. These suggest that the R-value, an effective scale for earthquake forecast, is 54% and may imply that the nonlinear earthquake flow function introduced in this paper can be applied to the intermediate-term earthquake forecast research. 相似文献
15.
断层附近强地震动半经验合成方法的研究 总被引：6，自引：2，他引：6
本文对利用经验格林函数法合成断层附近的强地面运动等问题做了初步研究。基于云南施甸5.9级主震和余震强震观测记录和本文提出的移动窗技术对断层附近的主震记录进行了分析识别，发现大震的Asperity(凸凹体）与小震在时程和Fourier幅值谱上存在一定程度的相似性。这种相似性从理论上，可以解释为这种小震视为大震Asperity的“种子”，大震的Asperity是由这些“种子”发育而成的。在此基础上合成了云南施甸距震中仅为1.1公里的主震记录，同时也提出以断层附近小震作为经验格林函数存在着一些缺陷。 相似文献
16.
龙陵 -澜沧新生断裂带的地震活动具频度高、强度大、周期短等特征 ,并以双震或震群型为主。断裂带由多条次级新生断层组成 ,呈斜列或共轭式展布 ,根据结构、规模、地震活动差异等因素把断裂带划分为 4个一级段、13个二级段 ,其中有 4个二级段又可划分出 8个三级段。历史上发生过大震、强震并有地震断层伴生的断层段为地震破裂单元 ;断裂带上晚第四纪有活动并有古地震事件 ,但无历史地震记载的地段为断层闭锁单元 ;次级断层之间的阶区或连接点为障碍体单元。从地震破裂特征分析 ,断裂带由破裂、闭锁、障碍体单元组成 ,根据地震、古地震、活断层、断层阶区的活动规律 ,断裂带可划分出 9个破裂单元、8个闭锁单元、10个障碍体单元。三者之间呈迁移、触发和转换能量的关系。根据这些关系和地震构造标志 ,对断裂带上未来可能发生大震、强震、中强震的地区分别作了预测。预测的危险区有 9个 ,其中大震区 1个 (永康 -永德地区 ) ,强震区 3个 (马站、石灰窑、酒房-勐混 ) ,中强震区 5个 (下顺江、里仁、大岗山、南明 -澜沧、勐遮 相似文献
17.
Introduction Yunnan is a very active region of earthquake in China. Since Yunnan Regional Seismological Network established in 1965, 37 years have past and thousands of seismic events have been recorded. Among them, 9 are great earthquakes of M7.0, more than 150 are moderately strong earthquakes of M =5.0~6.9 and about 6 000 are earthquakes of M3.0. Figure 1 shows the epicenter distribution of M3.5 earthquakes occurred in 1965~2002 in Yunnan region and Figure 2 the magnitude-frequency dis… 相似文献
18.
根据弹性回跳理论,有些断层上的大地震复发具有准周期性.强震的发生会对断层上大地震的复发周期产生影响.利用布朗过程时间(BPT)模型能够定量计算出一次强震对同一断层上大地震复发的延后时间.本文对断层上的强震对大地震发生率的改变量进行了研究,并以鲜水河断裂的几次地震为例,将由BPT模型计算的强震对大地震发生率的改变量与由库仑破裂应力计算的结果进行了比较.本文的研究表明,对于强震对大地震发生时间的延后幅度,使用BPT模型和库仑破裂模型计算的结果差别不大.周边强震对断层状态的加载使大地震复发时间的提前幅度可由BPT模型和库仑破裂模型计算,模型计算结果与现实震例相符.2014年11月22日康定M6.3级和M5.8级地震使鲜水河断裂带乾宁—康定段的大地震复发期望时间延后了36年,使磨西断裂的大地震复发期望时间提前了9年,从公元2086年提前至公元2077年. 相似文献
19.
对强震前的时序数据进行统计计算研究，发现若以特定地震带的时序数据为样本集，在强震前无标度区的跨度会相应地变长，反映出自组织程度的变化，以川滇地震带历史记录数据分析为例，若无标度区出现持续增长的征兆，则标志着地震活跃期的到来，同时可能伴有7级左右的地震，对于有的地震带关联维数出现变化不平缓的情况，也预示着地震活跃期的到来。但如果以地理区域划分如台湾省及全国的发震情况作为研究对象则无此规律。该结论在一定程度上可以提供一个强震发生中期预测的参考指标。 相似文献
20.
Relation between the characteristics of strong earthquake activities in Chinese mainland and the Wenchuan earthquake 
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下载免费PDF全文 This paper studies the relations between the great Wenchuan earthquake and the active-quiet periodic characteristics of strong earthquakes, the rhythmic feature of great earthquakes, and the grouped spatial distribution of MS8.0 earthquakes in Chinese mainland. We also studied the relation between the Wenchuan earthquake and the stepwise migration characteristics of MS?≥7.0 earthquakes on the North-South seismic belt, the features of the energy releasing acceleration in the active crustal blocks related to the Wenchuan earthquake and the relation between the Wenchuan earthquake and the so called second-arc fault zone. The results can be summarized as follows: ① the occurrence of the Wenchuan earthquake was consistent with the activequiet periodic characteristics of strong earthquakes; ② its occurrence is consistent with the features of grouped occurrence of MS8.0 earthquakes and follows the 25 years rhythm (each circulation experiences the same time) of great earthquakes; ③ the Wenchuan MS8.0 earthquake follows the well known stepwise migration feature of strong earthquakes on the North-South seismic belt; ④ the location where the Wenchuan MS8.0 earthquake took place has an obvious consistency with the temporal and spatial characteristic of grouped activity of MS≥?7.0 strong earthquakes on the second-arc fault zone; ⑤ the second-arc fault zone is not only the lower boundary for earthquakes with more than 30 km focal depth, but also looks like a lower boundary for deep substance movement; and ⑥ there are obvious seismic accelerations nearby the Qaidam and Qiangtang active crustal blocks (the northern and southern neighbors of the Bayan Har active block, respectively), which agrees with the GPS observation data. 相似文献