地震学报（英文版）2009，Vol.22Issue(5)：539-543,5.DOI:10.1007/s11589-009-0539-7
"Double low-points" anomaly in daily variation of vertical component of geomagnetic field before the MS8.0 Wenchuan earthquake
"Double low-points" anomaly in daily variation of vertical component of geomagnetic field before the MS8.0 Wenchuan earthquake
Jiuchang Hu 1Wei Liu 1Minrui Guo 1Hua Zheng1
作者信息
- 1. Earthquake Administration of Hainan Province, Haikou 570203, China
- 折叠
摘要
Abstract
The "double low-points" anomaly in daily variation of vertical geomagnetic component was observed on May 9, 2008 at 13 geomagnetic observatories belonging to the geomagnetic observatory network center of China Earthquake Administration. These observatories distribute roughly on three belts with the intersection in western Sichuan. On May 12, three days after the anomaly appearance, the great MS8.0 Wenchuan earthquake occurred. The "double low-points" anomaly in daily variation of vertical geomagnetic component is an anomalous phenomenon of regional geomagnetism, which does exist objectively. The possible cause is the change of extrinsic eddy current system resulting in geomagnetic daily quiet variation (Sq), or the delay of several hours between the intrinsic and the extrinsic eddy current systems. The relationship between the "double low-points" anomaly of daily geomagnetic variation and the earthquake reveals that the former possibly reflects the accelera-tive alteration of earthquake gestation in the deep Earth.关键词
Wenchuan earthquake/ geomagnetism/ vertical component/ double low-pointsKey words
Wenchuan earthquake/ geomagnetism/ vertical component/ double low-points分类
天文与地球科学引用本文复制引用
Jiuchang Hu,Wei Liu,Minrui Guo,Hua Zheng.."Double low-points" anomaly in daily variation of vertical component of geomagnetic field before the MS8.0 Wenchuan earthquake[J].地震学报（英文版）,2009,22(5):539-543,5.
