样本条件对加卸载响应比计算结果的影响分析
|
摘要
基于随机 Ｐｏｉｓｓｏｎ 模型和 Ｇｕｔｅｎｂｅｒｇ Ｒｉｃｈｔｅｒ 关系， 构造在 １０ 年尺度内样本量从 ３００ 到５ ０００ 的若干组模拟地震数据，计算分析各种样本条件下的加卸载响应比 Ｙ时间进程变化。结果表明，计算样本的震级上限 Ｍ ｔ 相对于ｌｏｇ Ｎ Ｍ 关系中拟合线性外推最大震级 Ｍ Ｔ 的变化对 Ｙ的异常分布有一定影响，其影响随地震样本量从小到大而明显减小。当滑动计算时间窗内地震样本为几十个量级， Ｍ ｔ 取为 Ｍ Ｔ － １．５（或至 ２．０）时，随机出现 Ｙ 大于 ２．０ 的高值异常分布频度明显降低。而当地震样本量达到上百个以上量级， Ｍ ｔ 取为 Ｍ Ｔ － ０．０（或 ０．５）时， Ｙ大于 ２．０ 的高异常值随机出现频度即极低。在实际地震资料的 Ｙ 计算中若注意 Ｍ ｔ 的选取后，其结果的稳定性和异常的可信度将得到显著提高。
Based on the stochastic Poisson Model and the Gutenberg Richest law, we simulated a set of earthquake catalogues, from 300 to 5000 events in each, and calculated how the load/unload response ratio (LURR), namely Y , varies with time under different sample conditions. The results show that the difference between upper magnitude threshold M t used in the calculation and the maximum magnitude extrapolated from the linear relation of log N～M has an influence on the distribution of Y . The effect decreases rapidly when the sample size of the earthquake events increases. When the number of events in the sliding time window for calculating Y increases to a quantity of several dozens, and M t is about M T -1.5 (or to 2.0), Y gets a much lower probability to be a high value greater than 2.0. When the above number of events reaches an order of magnitude of hundreds, and even Mt is about M T -0.0 (or to 0.5), Y also gets a very low probability to be a high value greater than 2.0. This research shows that if the upper magnitude threshold M T is considered when calculating Y from real earthquake catalogues, the stability of Y and the reliability of its anomalies will be much improved.
Based on the stochastic Poisson Model and the Gutenberg Richest law, we simulated a set of earthquake catalogues, from 300 to 5000 events in each, and calculated how the load/unload response ratio (LURR), namely Y , varies with time under different sample conditions. The results show that the difference between upper magnitude threshold M t used in the calculation and the maximum magnitude extrapolated from the linear relation of log N～M has an influence on the distribution of Y . The effect decreases rapidly when the sample size of the earthquake events increases. When the number of events in the sliding time window for calculating Y increases to a quantity of several dozens, and M t is about M T -1.5 (or to 2.0), Y gets a much lower probability to be a high value greater than 2.0. When the above number of events reaches an order of magnitude of hundreds, and even Mt is about M T -0.0 (or to 0.5), Y also gets a very low probability to be a high value greater than 2.0. This research shows that if the upper magnitude threshold M T is considered when calculating Y from real earthquake catalogues, the stability of Y and the reliability of its anomalies will be much improved.
引文
1 尹祥础.地震预测新途径的探索.中国地震.1987,3(1):1～7
2 尹祥础 ,尹灿.非线性系统失稳的前兆与地震预报:响应比理论及其应用.中国科学( B 辑),1991(5):512～518
3 尹祥础,陈学忠,宋治平,等.加卸载响应比:一种新的地震预报方法.地球物理学报,1994,37(6):767～775
4 Xiangch Yin, Xuezhong Chen, Zhiping Song,et al. A new approach to earthquake prediction: the Load/unload responseratio( L U R R) theory. P A G E O P H,1995,145(3/4):701～715
5 王海涛,彭克银,张永仙,等.新疆伽师强震群过程中加卸载响应比变化特征.科学通报,1998,43(10):1109～1111
6 梅世蓉,冯德益,张国民,等著.中国地震预报概论.北京:地震出版社,1993.328～344
7 王炜.利用 W eibull分布研究华北地区前兆震群的特征.中国地震,1987 ,3(4):13～22
8 邓永录,梁之舜著.随机点过程及其应用.北京:科学出版社,1992,17～115
9 宇津德治主编.李裕彻等译.地震事典.北京:地震出版社,1990.212～223
10 庄建仓,马丽.应力释放模型及中国几个地震区活动特征的模拟结果.地震学报,1998,37(1):48～59
2 尹祥础 ,尹灿.非线性系统失稳的前兆与地震预报:响应比理论及其应用.中国科学( B 辑),1991(5):512～518
3 尹祥础,陈学忠,宋治平,等.加卸载响应比:一种新的地震预报方法.地球物理学报,1994,37(6):767～775
4 Xiangch Yin, Xuezhong Chen, Zhiping Song,et al. A new approach to earthquake prediction: the Load/unload responseratio( L U R R) theory. P A G E O P H,1995,145(3/4):701～715
5 王海涛,彭克银,张永仙,等.新疆伽师强震群过程中加卸载响应比变化特征.科学通报,1998,43(10):1109～1111
6 梅世蓉,冯德益,张国民,等著.中国地震预报概论.北京:地震出版社,1993.328～344
7 王炜.利用 W eibull分布研究华北地区前兆震群的特征.中国地震,1987 ,3(4):13～22
8 邓永录,梁之舜著.随机点过程及其应用.北京:科学出版社,1992,17～115
9 宇津德治主编.李裕彻等译.地震事典.北京:地震出版社,1990.212～223
10 庄建仓,马丽.应力释放模型及中国几个地震区活动特征的模拟结果.地震学报,1998,37(1):48～59
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心