用F-K方法确定腾冲火山区震源机制*

介绍了计算理论地震图的 F- K方法在不同深度 ,不同震中距 ,不同震源类型的情况 ,表明这种方法在高频区和多层水平层状模型计算效果较好 ,适用于研究中小地震的震源机制。采用 F- K方法得到了发生在腾冲火山区的 3个地震的震源机制 ,结果表明地震 1和地震 2是走滑断裂 ,地震 3是逆断层。 3个地震的主压应力轴基本呈北西向 ,与云南地区主压应力轴方向基本吻合 ,因此 ,推断这 3个地震是构造地震。

Source Estimation in tengchong volcano Area using F-K method

The synthetic seismograms are computed by using F K method for a variety of conditions,such as various source types,relatively long range of epicentral distance and wide domain of frequency.The method can generally perform in a multi layered medium,and can be used for the purpose in the regional and local source mechanism.The source mechanism of the three earthquakes occurred in Tengchong volcano area is determined by this method.The result shows that the first event and the second event have strike slip faulting,and the third event has thrust faulting.The principal axis of compressive stress is oriented in NW direction,which tallies with the direction of tectonic field of Yunnan.It is inferred that they are tectonic earthquakes.