改进型PI方法提取地震电离层扰动异常的深入研究

发布时间：2018-07-03 19:05

本文选题：图像信息(PI)方法 + 改进型图像信息(MPI)方法　；参考：《中国地震局地震预测研究所》2015年硕士论文

【摘要】：本论文首先通过详细学习图像信息方法(Pattern Informatics Method,简称“PI”)在地震中长期危险性预测研究中的应用,进一步分析、总结了前人利用改进型图像信息方法(Modified Pattern Informatics Method,简称“MPI”)在地震电磁卫星资料中的应用,通过对DEMETER卫星观测资料进行消除长趋势变化的数值处理,提取电离层差异动态场,在数据处理上进一步改进和完善该方法在提取震前电离层异常信息的应用。通过较多的震例研究,以期获得地震电离层异常统计特征,并探讨浅源与深源地震、海洋与陆地地震之间异常的区别与联系。主要研究内容如下:1、本文通过总结国内外关于利用法国DEMETER卫星观测数据来识别和提取地震电离层扰动异常研究的主要方法研究以及所存在的问题,主要介绍了改进型图像信息方法(Modified Pattern Informatics Method,简称MPI方法)应用于提取地震电离层异常信息的研究进展与前景。2、为了更好地突出和提取地震所引起的电离层电子参量的扰动异常,本文对DEMETER卫星在2007-2009年观测的电离层电子浓度(Ne)、电子温度(Te)的数据进行了消除由太阳活动等引起的长趋势变化,以残差值来作为MPI方法的输入量,以期提高地震电离层扰动异常的信噪比。3、对比研究了海洋低纬地区和陆地中纬地区电离层的电子参量变化特征,发现:电子浓度(Ne)、电子温度(Te)随地理位置、地方时的变化分布特征基本相似。其中电子浓度值在海洋低纬地区明显高于陆地中纬地区,电子温度值陆地中纬地区高于海洋低纬地区,二者的变化曲线趋势基本一致。4、利用改进型图像信息方法(Modified Pattern Informatics Method,简称“MPI”),基于DEMETER卫星观测的电子浓度(Ne)、电子温度(Te)的残差值数据探索了14次2007-2009年全球7.0级、国内6.0级以上地震前出现的地震电离层电子参量异常现象,以期能够提取到由地震孕育与发生所引起的电离层扰动异常。结果发现,虽然不同震例出现的异常范围、异常形态及幅度有所不同,但震前一个月左右电子浓度(Ne)、电子温度(Te)等参量均出现了不同程度的扰动异常,震前10天左右异常减弱并趋于平静,相对于其他方法提取到的异常在震前几小时至数天内,这一突出特点将使MPI方法在短临地震预报中更具有可操作性。与以往类似的研究相比较,本文的创新点之一为在卫星数据处理上,进一步考虑由太阳活动等因素影响的长趋势变化,通过对长趋势变化消除获得的差异动态场更易提取高信噪比的地震电离层异常。创新点之二,实现了电离层扰动信息演化过程全时空、可对比资料处理,通过较多的震例研究,获得了更为稳定、客观的地震电离层异常信息,类似于气象卫星云图的电离层异常扰动图像全时空演化过程,有利于研究结果在地震短临预测实践中的应用,为我国地震电磁卫星观测试验积累经验。
[Abstract]:In this paper, the application of pattern Informatics method ("Pi") in the study of medium and long term earthquake risk prediction is studied in detail. This paper summarizes the application of modified pattern Informatics method ("MPI") in seismic electromagnetic satellite data, and extracts the ionospheric differential dynamic field by processing the observation data of Demeter satellite to eliminate the long trend change. The application of this method in extracting ionospheric anomaly information before earthquake is further improved and improved in data processing. The statistical characteristics of the ionospheric anomalies of earthquakes are obtained through the study of more earthquake examples, and the differences and relations between the anomalies of shallow and deep source earthquakes, ocean and land earthquakes are also discussed. The main contents of this study are as follows: 1. This paper summarizes the main methods and existing problems of identifying and extracting seismic ionospheric disturbance anomalies by using the observed data of the French Demeter satellite at home and abroad. This paper mainly introduces the application of modified pattern Informatics method (MPI) to the research progress and prospect of extracting seismic ionospheric anomaly information, in order to better highlight and extract the disturbed anomalies of ionospheric electronic parameters caused by earthquakes. In this paper, the data of ionospheric electron concentration (ne) and electron temperature (Te) observed by Demeter from 2007 to 2009 are used to eliminate the long trend changes caused by solar activity, and the residual value is used as the input of MPI method. In order to improve the signal-to-noise ratio (SNR) of seismic ionospheric disturbance anomaly, the variation characteristics of electron parameters in the ionosphere in low-latitude ocean and mid-latitude land are compared and studied. It is found that electron concentration (ne) and electron temperature (Te) vary with geographical location. The distribution of local time is basically similar. The electron concentration in the low latitude of the ocean is obviously higher than that in the middle latitude of the land, and the value of electron temperature in the middle latitude of the land is higher than that in the low latitude of the ocean. The trend of the two curves is basically consistent. Using modified pattern Informatics method (MPI), based on the data of electron concentration (ne) and electron temperature (Te) observed by Demeter satellite, the global magnitude of 7.0 was explored for 14 times from 2007 to 2009. In order to extract the ionospheric disturbance anomaly caused by earthquake preparation and occurrence, the phenomenon of ionospheric electron parameter anomaly appeared before the earthquake with magnitude 6.0 or above in China. The results show that although the anomalous range, shape and amplitude of the anomalies vary with different earthquake cases, the parameters such as electron concentration (ne) and electron temperature (Te) are disturbed to varying degrees one month before the earthquake. About 10 days before the earthquake the anomaly weakens and tends to calm. Compared with the anomaly extracted by other methods within a few hours to several days before the earthquake this outstanding feature will make the MPI method more operable in the short-impending earthquake prediction. Compared with similar studies, one of the innovations in this paper is to further consider the long trend changes influenced by solar activity and other factors in satellite data processing. It is easier to extract seismic ionospheric anomalies with high signal-to-noise ratio by eliminating the difference dynamic field. Second, the whole time and space of ionospheric disturbance information evolution can be realized, and more stable and objective seismic ionospheric anomaly information can be obtained through more seismic examples. The whole space-time evolution process of ionospheric anomalous disturbance images similar to meteorological satellite cloud images is beneficial to the application of the research results in the practice of short-term and impending earthquake prediction and the accumulation of experience for the seismo-electromagnetic satellite observation experiments in China.
【学位授予单位】：中国地震局地震预测研究所
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P315.728

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