地球磁场和人工磁场不断变化,会对甚宽频带地震计的簧片产生吸引而降低地震观测数据质量。将甚宽频带地震计分别采用宽背簧和窄拉簧悬挂,放置于赫尔姆霍兹线圈中间,测试地震计所受干扰;使用铍莫合金屏蔽罩罩住地震计,再次测试地震计所受干扰。测试结果表明:地震计垂直分向所受干扰严重,使用宽背簧支撑摆体运动的地震计所受干扰程度较大;铍莫合金屏蔽罩对参与测试地震计所有分向均有一定屏蔽效果。
The Earth's magnetic field and artificial magnetic field are constantly changing, which will attract the spring of very broadband seismometer and reduce the quality of seismic observation data. In this paper, two kinds of very broadband seismometers suspended by different shapes spring are placed in the middle of helmholtz coil to test the interference results of the seismometers, and then test the interference results of the seismometers are shielded with Beryllium and Mo alloy cover. The test results show that the most serious interference is vertical component. The interference degree of the seismometer supported by wide back spring is greater than the seismometer supported by narrow tension spring. Beryllium and Mo alloy shield cover has certain shielding effect on all components of the two type of seismometers.
2019,40(6): 87-92 收稿日期:2019-11-04
DOI:10.3969/j.issn.1003-3246.2019.06.013
基金项目:国家重点研发计划(项目编号:2018YFC1503904-03;2018YFC1503904-07)
作者简介:刘明辉(1976-),男,工程师,主要从事地震观测技术研究、应用与推广工作。E-mail:geodevice@sina.com
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