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

月球潮汐被怀疑引起地震已经有世纪了。 了解潮汐对地震发生的影响对于提高对地震开始时应力和应变模式的了解非常重要。更好地理解地震成核作用有助于预测地震。以前大多数关于地震是否对潮汐敏感的研究都没有定论。 研究人员最近完成的一个项目表明，当潮汐有利于应力时，地震发生率只比潮汐阻止地震时高出百分之几。本研究利用北方和加州中部圣安德烈亚斯断层的简单部分上的数万次地震，并使用包括月球、观测到的世界海洋潮汐和加州详细海岸线在内的复杂模型计算潮汐。本项目以更高的分辨率检查扩展数据集，并解析潮汐对地震的影响程度。 这项工作还将检查以确保几种可能的混淆效应，包括地震群和余震序列的时间聚类以及地震目录中人工制品的存在不会影响结果。一个精确的估计，月球潮汐对地震发生率的影响将产生。这项研究的结果将有助于寻找新的方法，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.