论文部分内容阅读
地震震源通常被看作为剪切位错源。从辐射的剪切波谱实际上并不能确定所有震源参数。首先,断层的滑动速度是控制高频辐射强度的真实的参数,可通过拟合高频成分加速度谱直接测定出。其次,因为频谱的拐角频率和震源半径二者的关系基本上不清楚,所以,不能用频谱准确确定震源的尺度。这种估计的精度和任何其他合理的猜测相同。第三,应力降在震源半径和拐角频率二者关系中只是代表了震源半径,因此不能从频谱准确地求出.通常从频谱求得并称之为应力降的这个量,其定义是粗略的,它与断层上实际的应力作用可能并没有什么关系。如果不转换成最大的滑动速度,应力降几乎没有什么意义。这是可以从频谱准确求出的唯一的物理量。从加利福尼亚事件的频谱求出的典型应力降值为100bar,这意味着典型的滑动速度为0.5m/s,事实上可以直接从频谱更准确地求出滑动速度。
Earthquakes are generally regarded as sources of shear dislocations. The shear spectrum from radiation does not in fact determine all source parameters. First, the slip velocity of a fault is a true parameter that controls the intensity of the high-frequency radiation and can be directly measured by fitting the acceleration spectrum of the high-frequency component. Second, since the relationship between the frequency of the spectral corner and the radius of the source is basically not clear, it can not be accurately determined by the spectrum. The accuracy of this estimate is the same as any other reasonable guess. Third, the stress drop in the relationship between the source radius and the corner frequency represents only the radius of the source and therefore can not be accurately determined from the spectrum, and the amount usually found from the spectrum and called the stress drop is defined as rough , It may not have anything to do with the actual stress on the fault. If you do not convert to the maximum sliding speed, the stress drop is almost meaningless. This is the only physical quantity that can be accurately derived from the spectrum. The typical stress drop calculated from the spectrum of events in California is 100 bar, which means that a typical slip speed is 0.5 m / s, in fact it is in fact straightforward to find the slip speed directly from the spectrum.