| 大同及邻区地震网格化相关分析及预测意义 |
| |
| 引用本文： | 沙海军,刘冬英.大同及邻区地震网格化相关分析及预测意义[J].中国地震研究,2012,26(3):391-398. |
| |
| 作者姓名： | 沙海军 刘冬英 |
| |
| 作者单位： | 中国地震局地壳应力研究所，北京 100085;中国地震局地壳应力研究所，北京 100085 |
| |
| 基金项目： | Research grant from Institute of Crustal Dynamics，China Earthquake Administration (No． ZDJ2011 － 01) and (No． ZDJ2010 － 26)． |
| |
| 摘 要： | 利用华北地区1970年～2009年的ML3.0级以上地震资料，使用相关分析方法,研究了大同及邻区的中小地震空间分布模式，及其在该区中强地震前的异常情况。研究工作首先是确定空间范围、时间窗和时间滑动步长，然后将地震的空间分布进行网格化再转化为序列；对一个时段和它的稍长时段的地震空间分布进行序列化，计算两个序列的相关系数；并分析相关系数在中强地震前是否明显变化。计算结果表明：当空间取以1989年大同-阳高5.9级地震震中为中心，经向长度和纬向长度均为1.6度的矩形区域，时段长度取3600天，稍长时段取3700天，滑动步长取100天的情况下，1980年～2009年的相关系数时间序列数值整体上稳定，在0.94～1之间波动，但在1989年山西大同-阳高5.9级地震、1991年山西大同5.8级地震与1999年山西浑源5.6级地震前2年均出现过相关系数小于0.94的异常现象，表明地震的空间分布上出现明显变化。并讨论了相关系数异常对于中强地震的前兆意义，可以得到以下3点认识：（1）大同及周边地区的中强地震前，中小地震空间分布模式发生显著变化，可作为2年尺度的震兆异常，为该区中期地震预测提供时间上的参考；（2）考虑到研究区的限定范围为震中周边0.8度以内，地震时空分布的相关分析结果对于地震地点的预测也具有指示意义；（3）相关分析可以为识别此类地震空间分布模式的异常变化提供帮助。
|
| 关 键 词： | 大同地震 地震时空分布 相关分析异常识别 |
Correlation Analysis of Gridding of Earthquakes in Datong and Its Surrounding Areas and Implication for Earthquake Prediction |
| |
| Sha Haijun and Liu Dongying.Correlation Analysis of Gridding of Earthquakes in Datong and Its Surrounding Areas and Implication for Earthquake Prediction[J].Earthquake Research in China,2012,26(3):391-398. |
| |
| Authors: | Sha Haijun and Liu Dongying |
| |
| Institution: | Institute of Crustal Dynamics, China Earthquake Administration, Beijing 100085, China;Institute of Crustal Dynamics, China Earthquake Administration, Beijing 100085, China |
| |
| Abstract: | On the basis of the earthquake ( M_L ≥3. 0 ) catalog in North China from 1970 to 2009,the pattern of temporal and spatial distribution of medium-small earthquakes in Datong and its surrounding areas is studied by correlation analysis with a focus on its anomaly before moderate and strong earthquakes. With different spatial scales,temporal scales and time steps, the spatial distribution of earthquakes is converted to a sequence, then the correlation coefficients between the spatial distribution of medium-small earthquakes in a long-term and a longer time are calculated for the analysis of anomalies before moderate and strong earthquakes. In the study region center on the epicenter of the 1989 Datong-Yanggao earthquake ( M_S 5. 9 ) within a radius of less than 0. 8°,with the time length of 3600 days,the longer time length of 3700 days,and the time step of 100 days, the correlation coefficient from 1980 to 2009 is steady between 0. 94 and 1. 00,but there were anomalies with values less than 0. 94 in the 2 years before the 1989 Datong-Yanggao earthquake ( M_S 5. 9 ) , the 1991 Datong earthquake ( M_S 5. 8 ) and 1999 Hunyuan earthquake ( M_S 5. 6 ) , which indicates the spatial distribution of a medium-small earthquake is very different from steady background seismicity. The implication for earthquake prediction from the anomaly of the correlation coefficient is also discussed with the three conclusions: ( 1 ) Before moderate and strong earthquakes in Datong and its surrounding areas,the obvious change of spatial distribution patterns of medium-small earthquake can be a kind of seismic precursor of the 2-year time scale for the prediction of an earthquake’s time. ( 2 ) As the study region is restricted within a radius of less than 0. 8°,the result of correlation analysis is also good for the prediction of an earthquake’s location. ( 3 ) The method of correlation analysis in this paper helps recognize the anomaly of spatial distribution of medium-small earthquake. |
| |
| Keywords: | Datong earthquake Spatial distribution of earthquakes Correlation analysis Anomaly recognition |
| 本文献已被 CNKI 等数据库收录！ |
| 点击此处可从《中国地震研究》浏览原始摘要信息 |
| 点击此处可从《中国地震研究》下载免费的PDF全文 |
|
