易门地倾斜前兆综合分析的初步研究

THE PRELIIVIINARY STUDY ON THE SYNTHETIC ANALYSIS OF TILT PRECURSORS AT YIMEN STATION

本文应用莱柯拉兹滤波和别尔夫捷调和分析方法,对易门地倾斜固体潮观测资料进行处理;结合测点附近的区域地质构造特点、地震活动性和误差理论进行综合分析。数据处理和综合分析结果表明:易门地倾斜固体潮观测稳定,精度亦佳;测点地区内的大震前,均有前兆异常存在;测点所在地震带内的中强震前,有前兆异常存在;测点附近较近地区的中强震前,有时有前兆异常存在;大震及其前兆对地倾斜观测精度有直接影响;大震前存在一种集群性多台、多手段、多方法的前兆异常现象;在未来的一年时间内(1991年),云南地区不存在七级以上地震的危险。

In this paper, Le Colazet and Hepueo harmonic analytic method is used to process the tilt earth tide data observed at Yimou station. And a synthetic analysis is done in combination with the regional structural characteristic and earthquake activity around the station, and the error theory as well. The obtained results indicate that. 1 ) The tilt earth tide observation at Yimen station is stable, with a satisfactory precision. 2 ) There are always precursory anomalies existed before large events within observational areas.3) There are precursory anomalies existed before moderate events within the seismic belt where the station is located.4)There are sometimes precursory anomalies existed before moderate events in the near surrounding areas of the station. 5) Large events and their precursors directly affect the precision of filt observations. 6 ) There is a kind of clustering multi-station, mulli-approach and multi-method precursory anomalous phenomena existed before large events. 7) There doesn't exist a probability ot an event over magnitude. 7.0 in Yunnan Area in the forthcoming year (1991) .