1990年10月20景泰地震的活动图象及其特征

SEISMIC PATTERN AND CHARACTERISTICS OF THE JINGTAI EARTHQUAKE OF OCT. 20, 1990

摘要:

本文研究了甘肃景泰6.2级地震的活动图象及其特征。该次地震的类型属主震余震型。其地震活动的特征表现为:强震前中小地震活动图象发生变化,临震前出现中小地震活动条带;震前中小地震活动时间分维值下降并出现最低值;该次地震发生于6级地震等间距分布的格局中,并呈现明显的补位特征。本文还提出了一种利用震级测定值最大的台站的方位,确定地震破裂面的方向和节面展布的方向的方法。

Abstract:

On Oct. 20. 1990, there occurred a earthquake with magnitude of 6.2 in Jingtai area, Gansu. which is main-aftershock type. The seismic active feature shows:before strong earthquake, the distribution pattern of moderate and small events changed, the seismic belt appeared impending main shock:the time fractal dimension value decreased and got the minimum, the position style of equo-distance distribution of earthquakes with magnitude of 6 occurred nearby was characterized by filling location obviously. Also. this paper suggested a new method to rapidly obtain the trend of seismic rupture and nodal face from the position of stations, relative to epicentre, with the maximum values of magnitude determined.