美国圣安德烈斯断裂带强震活动规律及未来趋势研讨

Tendency judgement of M_w≥6. 8 earthquake in San Andreas fault

本文选取1900年以来圣安德烈斯断裂带M_w≥6.8强震数据,在可公度理论和对称性原理的基础上,采用蝴蝶结构图和可公度结构系方法分析了圣安德烈斯断裂带M_w≥6.8地震的时空对称性,并探讨可能触发地震的主要天文因素,从强震触发机理上验证了预测结果的可靠性。结果表明:圣安德烈斯断裂带M_w≥6.8历史地震可公度性良好,2017年发震信号较强。历史强震震中空间上呈现明显的"西北-东南"对称回旋迁移规律,由此判断下次强震往东南方向(116°W,34°N附近)迁移可能性较大。相关分析显示,在地球自转速度变化率较大的年份该断裂带易发生强震,且多数强震发生在太阳黑子峰值年,这也进一步佐证了2017年该地区发生强震的可能性。

Natural disasters,especially earthquakes,characterized as sudden,disastrous and difficult to predict.Therefore,to have an accurate judgement on the tendency of this disasters is of great theoretical and practical significance. Based on the seismic data（ M_w≥6. 8） in San Andreas Fault area,the signal intensity of strong earthquakes tendency was analyzed and judged by using the methods of commensurability information. The author also applied butterfly structure diagram and commensurability structure system to analysis the earthquake＇s spatiotemporal symmetry and prove the reliability of the forecast result. To reveal how the astronomical factors effect strong earthquake activities,the paper analyzed the connection between strong earthquakes and Sunspot activities,the change of Earth＇s rotation speed. The results show that： The seismic in San Andres Fault has good commensurability. The signal showed earthquake will occur in 2017 is strong with the random probability of55. 6%. Furthermore,the butterfly structure diagram and commensurability structure system verified this judgement. In recent 115 a, the epicenter showed a ＂Northwest-Southeast ＂ symmetrical swing migration phenomenon,and the next earthquake is very likely to occur in the southeast. The years when the Earth rotation rate have a significant change is more likely to occur strong earthquakes,and most strong earthquakes occurred in the years that sunspot number reached to its maximum.