形变场多重分形谱异常与强震关系研究

以平均形变速率梯度概率为变量, 研究了唐山地区、甘肃河西地区和北京地区多期垂直形变场图像的动态多重分形特征及其与强震的关系。结果表明, 震前一至数年形变场图像的多重分形谱Dq 值域变宽, 即- q 区上翘, + q区下降现象, 在强震孕育发生的过程中, 形变场时空表现出从准均匀到不均匀的演化趋势。结合地震活动和岩石力学实验结果认为, 形变场不均匀化可能是中长期地震复杂性前兆的一个重要标志。

On the relation between multifractal anomaly of crustal deformational field and strong earthquakes

using the gradient probability of crustal vertical deformation rate as the variable, the multifractal properties of several areas where strong earthquake occurred were studied, including Tangshan area, Hexi area and Beijing area. The result s show that Dq value ranges of multifractal spectra widen, that is, the Dq values in the-qside climb up, and those in the+q side drop down one to several years before strong earthquake occurrence. It suggests that the strengthening process of deformation distribution from sub-inhomogeneity to inhomogeneity ( complexity ) before earthquake occurrence is common or repeatable. So, it can be inferred that the anomaly of deformation field complexity strengthening maybe a qualitative precursory index for strong earthquake prediction.