河北唐山古冶5.1级地震前的重力变化

(1.河北省地震局流动测量队,河北保定 071000;2.云南省地震局,昆明 650024)

唐山古冶5.1级地震;重力变化;零等值线

Gravity Changes before the Guye MS5.1 Earthquake in Tangshan,Hebei Province
LIU Hongliang1,WANG Qinghua2*,ZHANG Zhanwei1,YANG Yahui1,LIU Shufeng1

(1. Mobile Survey Team of the Hebei Earthquake Agency,Baoding 071000,China;2. Yunnan Earthquake Agency, Kunming 650024,China)

Guye MS5.1 earthquake in Tangshan;Gavity changes;Zero contour

DOI: 10.13512/j.hndz.2021.02.10

备注

利用京津冀地区2018—2020年5月的流动重力观测资料,分析了2020年7月12日河北唐山古冶5.1级地震前不同时间尺度重力场变化。结果 表明: 0.5年尺度重力场变化图像较好地反映了此次地震“震前一年,重力场持续上升(正)变化→震前反向变化→在重力变化梯度带零等值线附近发震”的演化过程;震前0.5年和1年年尺度重力场均显示,地震发生在重力变化零等值线附近。

Based on the mobile gravity observation data of Beijing,Tianjin and Hebei region from 2018 to 2020,the paper analyzed the dynamic changes of regional gravity field at different spatial-temporal scale before Guzhi Ms5.1 earthquake in Tangshan,Hebei on July 12th,2020. The results show that:the half-year-scale gravity changes image before the earthquake better reflects “one year before the earthquake,the gravity field continued to rise(positive)change → reverse change before the earthquake → earthquake occurred near the zero contour of the gravity change gradient zone”the evolution process. The half-year-scale and one-year-scale gravity field changes before earthquake show that the earthquake occurred near the zero contour lines of gravity changes.

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