Results from OSNPE: Improved Teleseismic Earthquake Detection at the Seafloor
Results from OSNPE: Improved Teleseismic Earthquake Detection at the Seafloor
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OSNPE 的结果：改进海底远震地震检测
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
R. Stephen
中科院分区：
文献类型：
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作者：
F. Sutherland;F. Vernon;J. Orcutt;J. Collins;R. Stephen
通过计算P波、S波、Rayleigh波和Love波到达的阈值检测震级，比较了位于（1）海底、（2）埋在海底沉积物中和（3）钻孔中的三个海洋地震台网（OSN）传感器与夏威夷岛台站的地震数据。
我们的研究结果表明，钻孔地震计的噪声水平类似的岛屿站，并产生高质量的高和低频率的体波和面波数据。浅埋在沉积物中的地震仪没有影响较高的频率，但显着降低了低频噪声水平，使S波和瑞利波的数据是高质量的。事实上，埋在地下的地震仪的特点是在非常低的频率下噪音水平最低（<20 mHz;柯林斯等人，2001年）。海底地震计始终存在噪音，产生的数据质量较低。
观察到的幅度和计算的阈值幅度都比以前的研究中观察到的幅度低一个数量级以上。特别是在钻孔仪器的短周期体波的结果比以前发现的任何海底记录好得多。
2003年5月5日收到Mandarin pt。
Earthquake data from three ocean seismic network (OSN) sensors, located (1) on the seafloor, (2) buried in seafloor sediments and (3) in a borehole, together with those from Hawaiian Island stations, were compared by calculating threshold-detection magnitudes for P -, S -, Rayleigh-, and Love-wave arrivals.
Our results show that the borehole seismometer had noise levels similar to those of the Island stations and produced high-quality high- and low-frequency body- and surface-wave data. Shallow burial of the seismometer in the sediments had no effect on higher frequencies but significantly reduced low-frequency noise levels so that data for S and Rayleigh waves were of high quality. In fact, the buried seismometer was characterized by the lowest noise levels at very low frequencies (<20 mHz; Collins et al. , 2001). The ocean-floor seismometer was consistently noisy, and the data produced were of lower quality.
Both observed magnitudes and calculated threshold magnitudes were lower by more than an order of magnitude than those observed in previous studies. Results for short-period body waves at the borehole instrument in particular were much better than those that were previously found for any ocean-bottom recording.
Manuscript received 5 May 2003.