CAJ | 학술논문

重标极差分析法(R/S,rescaled range analysis method),是研究分数布朗运动及自然现象的自仿射分形的有力工具之一,对于所有时间序列分析都有着广泛的用途.通过对天水台绝对地磁观测Z分量数据序列R/S分析,计算分段数据序列的Hurst指数H发现,昆仑山口西M_S8.1地震和汶川M_S8.0地震震前2-3个月,H值减小,分维数D增大,相关系数C为负值.这一动态变化表明,地震前数据序列由持久性序列发展为反持久性序列,观测数据的成分发生了改变.这与地壳内部应力变化和岩石破裂实验结果相符.所以,这一动态变化过程可以看作是强震前的一种前兆信号.
중표겁차분석법(R/S,rescaled range analysis method),시연구분수포랑운동급자연현상적자방사분형적유력공구지일,대우소유시간서렬분석도유착엄범적용도.통과대천수태절대지자관측Z분량수거서렬R/S분석,계산분단수거서렬적Hurst지수H발현,곤륜산구서M_S8.1지진화문천M_S8.0지진진전2-3개월,H치감소,분유수D증대,상관계수C위부치.저일동태변화표명,지진전수거서렬유지구성서렬발전위반지구성서렬,관측수거적성분발생료개변.저여지각내부응력변화화암석파렬실험결과상부.소이,저일동태변화과정가이간작시강진전적일충전조신호.
Rescaled range analysis(R/S)method is one of the good tools for studying fractal Brownian motion of time-series data and natural phenomena self-affine fractal, being applied widely for all time-series. In this paper, this method is used to analyze absolute geomagnetic Z component observations at Tianshui Observatory. The Hurst exponent H was calculated for each sub-sequence of data in specific time intervals. Our analysis result indicates that, 2-3months before Kunlun M_S8. 1 earthquake and Wenchuan M_S8. 0 earthquake, H value decreased and fraetal dimension value D increased. Such dynamic variations manifest that the observations varied from persistent behaviour to antipersistent time-series before the earthquakes and the composition of the observed data changed. This variation is consistent with internal crustal stress change and rock failure experiment results. So we may view this dynamic variation as a premonitory symptom of the strong earthquakes.