Source Parameters Variations Among Oceanic Earthquakes and Tectonic Implications

这项研究是利用地震学确定的地震应力降，研究海脊上的洋壳相对剩余大洋岩石圈的强度和变形。初步结果显示，相对体波和面波震级、地震矩和震源时间函数有几个有趣的差异。这些数据表明，就板内地震而言，山脊地震一般是“快”的(短周期优先释放能量)，而转换地震一般是“慢”的(长周期优先释放能量)。利用震源模型，研究人员发现，这些差异与山脊事件的应力降高于转换事件是一致的，这意味着山脊处相对较薄的地壳具有更高的强度。这项研究旨在扩大数据集，继续和完善地震学分析，并探索构造意义。

This research deals with the investigation of relative strengths of oceanic crust at ridges and transforms relative to the remaining oceanic lithosphere by means of seismologically-determined stress drops from earthquakes. Preliminary results show several interesting differences in the relative body and surface wave magnitudes, seismic moments, and source time functions. These data suggest that with respect to intraplate events, ridge earthquakes are generally "fast" (releasing energy preferentially at short periods) whereas transform earthquakes are generally "slow" (releasing energy preferentially at long periods). Using seismic source models, the investigators have found that these differences are consistent with ridge events having higher stress drops than transform events, which implies a higher strength of the relatively thin crust at ridges. This research seeks to expand the data set, continue and refine the seismological analysis, and explore the tectonic implications.