High-resolution Study of the Correlation of Earthquakes and Earth Tides: Constraints on Earthquake Nucleation

一个多世纪以来，人们一直怀疑月球潮汐会引发地震。重要的是要了解潮汐对地震发生的影响，以便更好地了解地震开始时的应力和应变模式。更好地了解地震成核作用有助于预测地震。以前关于地震是否对潮汐敏感的研究大多没有定论。研究人员最近完成的一个项目表明，当潮汐有利于应力时，地震率比潮汐阻止地震时高出不超过几个百分点。这项研究使用了加利福尼亚州北部和中部圣安德烈亚斯断层简单部分的数万次地震，并使用复杂的模型计算潮汐，包括月亮、世界海洋中观测到的潮汐和加州详细的海岸线。该项目检查了一个更高分辨率的扩展数据集，并解决了潮汐对地震的影响程度。这项工作还将进行检查，以确保几种可能的混杂影响，包括地震在时间上聚集成震群和余震序列，以及地震目录中人工制品的存在不会影响结果。将对月球潮汐对地震发生速度的影响进行精确的估计。这项研究的结果将有助于寻找新的途径，以进一步提高对地震成核的理解。

The lunar tide has been suspected of causing earthquakes for more than a century. It is important to understand the influence of tides on the occurrence of earthquakes to improve understanding of the stress and the strain patterns just as an earthquake begins. A better understanding of earthquake nucleation could aid attempts to predict earthquakes.Most previous studies of whether earthquakes are sensitive to tides have been inconclusive. A recently completed project by the investigators showed that earthquake rates are no more than a few percent higher when tides favor stresses than when tides act to discourage earthquakes. This work used tens of thousands of earthquakes on simple parts of the San Andreas fault in northern and central California and computes the tides with a sophisticated model including the moon, the observed tides in the world's oceans, and the detailed coast line in California.This project examines an expanded dataset with greater resolution and resolves the level of tidal influence on earthquakes. The work will also check to be sure that several possible confounding effects, including the temporal clustering of earthquakes into swarms and aftershock sequences and the presence of artifacts in earthquake catalogs do not affect the results. A refined estimate of the effect of lunar tides on the rate of earthquake occurrence will be produced. Results of this study will be useful in the search for new ways to further improve understanding of earthquake nucleation.