Estimating Radiated Seismic Energy over 17 Orders of Magnitude

本研究探讨了辐射地震能量作为地震规模的函数的标度。辐射能量只是最近才被研究，以前的可靠估计很少。然而，新的工具，如日本的K-Net，可以进行更可靠的估计。因此，本研究为地震辐射能量的估算提供了新的结果。日本浅层（0-50公里）中强（M4-6）地震的能量估计。我们分析了115次地震。为了对能量进行可靠的估计，确定了数百个K网络站点的站点校正。我们发现能量近似与力矩成正比。然而，由于震级范围有限，仅从这些数据很难看出任何趋势。这些结果与加利福尼亚州浅源地震的结果相似。我们比较了浅源地震和深源地震的能量估计。分析了来自北海道和东北的32个浅地震和37个深地震。为了进行可靠的能量估计，确定了这一数据集的场地校正和路径衰减。当比较浅源地震和深源地震的能量时，浅源地震的能量矩比随着地震规模的增加而增加。而对于深源地震，能量矩比是一个常数，是地震尺度的函数.我们对1994年加州北岭地震的余震做了一些详细的研究。这项工作证实，对于在加州的浅源地震，能量与力矩的比例增加作为地震规模的函数。

This research investigated the scaling of radiated seismic energy as a function of earthquake size. Radiated energy has only recently been studied and previous reliable estimates are few. However, new instrumentation, such as K-Net in Japan allows more reliable estimates. So this research provides new results about the estimates of radiated energy of earthquakes.There were 3 main studies.1. Energy estimates for shallow (0-50 km) moderate (M4-6) earthquakes in Japan. We analyzed 115 earthquakes. To make reliable estimates of energy, station corrections for several hundred K-Net sites were determined. We found that the energy is approximately proportional to the moment. However, since the magnitude range is limited, it is difficult to see any trend from just these data. These results are similar to results for shallow earthquakes in California.2. We compared of energy estimates of shallow and deep earthquakes. 32 shallow and 37 deep events from Hokkaido and Tohoku were analyzed. To make reliable energy estimates, site corrections and path attenuation were determined for this data set. When comparing energies of shallow and deep earthquakes, the shallow earthquakes show an increase of energy to moment ratio, as a function of earthquake size. While for deep earthquakes the energy to moment ratio is constant as a function of earthquake size.3. We did some detailed work on aftershocks of the 1994 Northridge, California earthquake. This works confirms that for shallow earthquakes in California, the ratio of energy to moment increases as a function of earthquake size.