1983年菏泽5.9级地震前后沂水泉氡的变化

沂水泉位于山东省沂水一汤头断裂带上。多年来的观测分析表明,影响沂水泉氡值变化的最大干扰是降雨。由于这种干扰存在着“记忆”滞后影响,所以用一般的相关分析难以将这种影响排除干净。本文对最小二乘法为建立模型的判据,用动态灰箱分析法拟合并推估观测系统的变化。在分析中用了四个状态变量：长趋势成分Ｌ（ｔ）、年周期变化成分Ｐ（ｔ）、降雨影响部分Ｒ（ｔ）和随机变化部分Ｓ（ｔ）。经过分析表明,沂水泉氡的长趋势部分１

VARIATION OF YISHUI SPRING RADON AROUND HEZE EARTHQUAKE Ms=5.9, 1983

The Yishui spring is located along the Yishui-Tangtou fault zone. Observation and analysis for many years show that the precipitation is the greatest disturbance affecting the variation of water radon in Yishui spring. Because there exists "memory" lag influence in this disturbance, such an influence is difficult' to be completely removed by using the general relative analysis.Based on the systematic theory and cybernetics, this paper processed the precipitation factor with memory influence by adopting the convolution filtering method and taking the least square method as the criterion for the model establishment, the paper also fitted and estimated the change of observational system through the dynamic gray-box analysis method. Four state variables were used in the analysis: long-tendency composition L(t), annual cyclical compositon P(t), part of precipitation influence R(t) and part of radon change S(t).Analysis show that the long-tendency composition from 1979-1981 in Yishui spring belongs to the normal variation. It began to drop gradually since 1982 and was beyond 4 times the mean error till November, 1983. It turned to rise after Heze earthquake Ms - 5.9. There also began to appear the anomalous variation of the deviation of radon content in Yishui spring.However, the anomaly is not seen from the observed curve of the Yishui springradon and curve after the processing by using the general method, it can be seen thatthe processing method here is of certain superiority. The processing method in thispaper is suitable for the observed data of water radon with obvious annual cyclicalchange.