确定地壳形变观测曲线趋势转折点的定量方法与实例

趋势转折是地壳形变变化的一个重要信息,为定量、精确地提取地壳形变观测资料的趋势转折点,基于改进的有序聚类分析法,采用时窗滑动的方法,提取时间序列的趋势转折点,并编制了相应的程序.以新源地震台地倾斜南北向1992～2006年的观测数据为例,以4年窗长、2年步长滑动计算其趋势转折点.研究结果表明：（1）采用改进的有序聚类分析法提取时间序列的趋势转折点具有明确的统计意义,可减少人为判断的主观和任意性.（2）该方法算法简单,易于实现,可用于日常的地壳形变观测资料的分析预报工作.（3）新源地震台地倾斜南北向观测数据计算结果表明,在2001年之前,趋势转折比较频繁,变化也比较明显,而在2001年之后,趋势转折较少,变化更接近线性.

QUANTITATIVE EXTRACTING METHOD AND EXAMPLE FOR TREND TRANSITION POINTS OF CRUSTAL DEFORMATION OBSERVATION DATA

Trend transition is important information in crustal deformation data analysis. In this paper, for extracting the transition points of time series quantitatively and precisely, we study the improved sequential cluster method with moving time-window and compile the computer program. As an example, we deal with the ground tilt data about NS in Xinyuan seismic station from 1992 to 2006 with 4 years window-length and 2 years step-size. The results show that： （ 1 ） the method of improved sequential cluster analysis has an explicit statistic meaning, and it can reduce the subjectivity and arbitrariness in study. （2） The algorithm of this method is very simple, can use easily in analysis and prediction for crustal deformation observation. （3） The calculation result of Xinyuan station suggest that the trend transition was frequent and obvious relatively before 2001, whereas, after 2001, it was rare and more like linear.