摘要
讨论了2006年4月9日范县ML4．7级地震前后重力场的变化和预测过程。震前2005年9月-2005年12月重力场表现为趋势下降，在2006年3月重力场转折上升，表现为变化加速，地震发生在重力场加速变化过程中。部分测点点值、测段段差值存在异常，点值和段差值的变化幅值在（30-60）×10^-8m·s^-2之间。震后该区的重力异常没有恢复。重力变化可能是由该区地壳形变、地壳深部质量迁移和断层蠕动共同作用引起的。
The variation of gravity field before and after Fanxian ML4.7 earthquake, which occurred on Apr. 9, 2006, is discussed. From September of 2005 to March of 2006 before the earthquake, the gravity field showed a decreasing tendency, but turned to fast increasing at March of 2006, and the earthquake occurred in the process of acceleration. The gravity values at parts of the sites and some segment showed some anomalies, with magnitude at 30～60× 10^-8m· s^-2 The gravity values did not recover after the earthquake. Variations of gravity field in this area may be caused by crustal deformation, quality transition in deep crust and fault creep.
出处
《华北地震科学》
2008年第1期17-21,共5页
North China Earthquake Sciences
关键词
范县地震
重力异常
地震活动性
地震预测
Fanxian earthquake
anomalies of gravity
seismicity
earthquake prediction
