Intermagnitude Relationships and Asperity Statistics

作者：Alexander Sasha Gusev · 发表于：Birkhäuser Basel eBooks · 年份：1991 · DOI：10.1007/978-3-0348-8654-3_11 · 被引用次数：27 · 研究领域：earthquake and tectonic studies、Earthquake Detection and Analysis、Seismology and Earthquake Studies

Several data sources appeared recently which enable one to construct an updated version of global average intermagnitude relationships. A set of nonlinear magnitude vs M w (or log M o) curves is presented. Several regional scales are also included in the set. Utilization of M w as a referential scale provides the optimal basis for extrapolation of return periods, strong motion amplitudes and source parameters from moderate to large earthquakes. Remarkable features of the constructed curves are: (1) practical coincidence of modified m b scale with m SKM of the Soviet Seismological Service (except the constant shift of 0.18); (2) the lack of true saturation of all scales but m b with the possible exception of m B for M w > 8.7; (3) almost common shape of curves for all short-period magnitudes (global as well as regional); (4) lack of a systematic world-averaged difference between American and Soviet M s. For M o large enough, m SKM (or) vs log M o trend has the slope b = 0.35. Data are compiled to estimate short-period spectral level vs log M o trend, and its slope seems to be near ß = 0.39. These two values and some additional assumptions, rather common, lead to the following conclusions regarding properties of the earthquake source and its short-period radiation: (1) peak to rms amplitude ratio (peak factor) of a short-period record grows as, hence the Gaussian noise model of the record (predicting) can be definitely rejected, and some heavy-tailed peak distribution is to be ...