丽江地震前后重力场变化的有限矩形位错模型分析  

ANALYSES ON GRAVITY VARIATION BEFORE AND AFTER THE LIJIANG EARTHQUAKE BASED ON A FINITE RECTANGULAR DISLOCATION MODEL

作　　者：燕乃玲[1] 李辉[2] 申重阳[2] 

机构地区：[1]中国科学院南京地理与湖泊研究所 [2]中国地震局地震研究所,中国武汉430071

出　　处：《地震学报》2003年第2期172-181,共10页Acta Seismologica Sinica

基　　金：地震科学联合基金(101005)"地壳运动与地壳密度的耦合运动研究"资助.

摘　　要：研究了用有限矩形位错模型计算地壳形变引起的地面重力场变化的方法。以丽江M_s7.0地震为例,讨论了确定用于模型计算的断层面参数的原则,并给出了结果。计算和分析了不同类型位错引起的重力场变化图象特征,并与丽江地震前后观测到的重力场变化进行比较。结果表明,在发震断层有限范围内模型可解释同震重力场的变化,但模型对于更大空间范围上的重力场变化并不能给出很好地解释。The methods were discussed to calculate the gravity variation due to crustal deformation based on a model of dislocation on a finite rectangular plane. Taking the Lijiang Ms = 7. 0 earthquake as an example the calculating principle of fault parameters were determined, and the results were given. Of particular interests were the characteristics of the gravity changes in different dislocation types. With comparison between the calculated results and the practical measurements, it was found that the model could to some extent account for the observations. But it failed to give explanations to the more spatial gravity variation.

关 键 词：有限矩形位错模型 同震重力场变化 丽江地震 断层运动 

分 类 号：P315.726[天文地球—地震学]