Deephole Three Component Seismic Observations at Cajon Pass, California

本研究是在Cajon Pass钻孔深处放置一个三分量地震仪。在井深3.5公里处，这是很重要的，因为这是结晶岩中的发震活动区，对当地地震事件的深度采样增加了我们对P波和S波地震谱组成部分的理解，以及不受近地表现象干扰的地壳地震尾波。如果地震发生的时空统计特性，例如b值和尾值Q，包含重要的前兆信息，则可以从放置在深处的传感器获得最大和最清晰的地震记录样本集。这项研究是国家减少地震危害计划的一个组成部分。

This research is to emplace a 3-component seismometer at depth in the Cajon Pass borehole. At the 3.5 km depth of the borehole, this is important because this is a zone of seismogenic activity in crystalline rock, and deep sampling of local seismic events increases our understanding of the components of the P- and S- wave seismic spectra and the seismic coda in crust undisturbed by near surface phenomena. If spatial and temporal statistical properties of earthquake occurrence, for example, b-values and coda Q, contain important precursory information, the largest and cleanest seismogram sample set is available from sensors placed at depth. This research is a component of the National Earthquake Hazard Reduction Program.