Precise Dating and Location of Prehistoric Earthquakes Using Tree-Ring Analysis

我们在约会和定位一个少校方面的初步成功 地震，以前未知的，在圣安德烈亚斯断层是 这是多年来广泛抽样和分析的结果。 的 最终产品是一个日历日期，给出了一个确切的时间间隔， 这一事件和1857年的历史记录中的一个事件。 的 地震的影响是，该地区的应变释放可能是 而不是周期性的。 在此建议进一步 将树木年轮测年应用于古地震学。 树木年轮分析是 几乎是独一无二的， 地震等事件。 这是每个人的绝对约会， 每年的年轮之前，检查扰动，使 该应用程序确定是否存在较早事件， 我们研究地区西北部，靠近加州的赖特伍德;研究 海湾地区1838年事件的范围;精确的日期 在小鲑鱼断层的东南端的事件 卡斯卡迪亚俯冲带;并调查南部的一个地区 意大利的条件似乎非常有希望的定位 在活跃的地震区没有记录的地面破裂。 的 从我们以前的研究中获得的知识，包括 失望，使我们能够有效地运作， 以更好的区域为目标进行分析。 另一个优化步骤 结果是包括地震学家熟悉或工作 在拟议的研究领域。 提供的背景资料 他们帮助定义具体问题和解释 任何结果的地震意义。

Our initial success in dating and locating a major earthquake, previously unknown, on the San Andreas fault was the result of extensive sampling and analysis over several years. The end product is a calendar date giving an exact interval between that event and an event in the historical record in 1857. The seismic implications are that strain release in the area may be episodic rather than periodic. It is herein proposed to further apply tree-ring dating to paleoseismology. Tree-ring analysis is virtually unique in being able to absolutely date site-disturbing events like earthquakes. It is the absolute dating of each and every annual ring prior to examination for disturbance that makes this application determine if there was an earlier event just to the northwest of our study area near Wrightwood, California; study the extent of the 1838 event in the Bay area; precisely date an event on the Little Salmon fault at the southeast end of the Cascadia Subduction zone; and to investigate an area in southern Italy where conditions seem very promising for locating undocumented ground ruptures in an active seismic region. The knowledge gained from our previous studies, including the disappointments, has equipped us to operate efficiently and to target better zones for analysis. Another step to optimize results is the inclusion of seismologists familiar with or working in the proposed study areas. The background information furnished by them aids in defining specific questions and in interpreting the seismic significance of any results.