摘要
重力基点网是我国开展地质调查、地震监测、测绘等测量工作的重要基础设施,面对原有基点网覆盖面不足且受到不同程度损害这一现状,目前已不能满足开展大比例尺重力调查以及高频率重复监测等工作的需求.本文以广西重力基点网重建为契机,利用A10-022绝对重力仪对全区42个重力基点与2个相对重力仪标定场的绝对重力值进行了测定.整个实施周期涵盖了计量参数校准、全球绝对重力仪国际比对、室内同点重复性以及全网部分基点独立安装检查等较为完整的测量流程,并通过连续运输与观测期间环境因素的记录与对比分析,总结了适合于该类型仪器室外条件下工作的技术手段与应对措施.观测结果表明:利用A10绝对重力仪能够高效率与高精度的完成广西重力基点网室外设计点位测定工作,国际比对及重复性验证确保了本次重建基点结果的可信度;A10采用双模式的氦氖激光频率存在漂移并受温度及气压等多种因素的综合影响,但短期内中心频率未出现较大波动,建议定期对其进行校准;各基点观测误差主要受到台站质量、人文活动及突发事件等环境扰动的影响,并与仪器内外温差存在较高的相关性.本文给出的A10绝对重力仪的参数设计、技术手段与影响因素的详细分析,能够为今后同类型仪器的观测实施提供重要参考,并有助于室外绝对重力观测的全国推广与应用.
Gravity base network is an important infrastructure for geological surveys, earthquakes monitoring and geodesy working in China. The existing base network is currently unable to meet the need for large-scale gravity surveys and high frequency repetitions, due to current situation of inadequate coverage and serious damage of basic points. In this study, we used A10-022 absolute gravimeter to measure absolute gravity value of 42 gravity points and 2 relative gravimeter calibration fields (short baselines) in Guangxi. The entire period covers complete observation processes including calibration of metrological parameters (i.e., laser and atomic clock), 2017 International Comparison of Absolute Gravimeters (ICAG-2017), indoor repeatability and independent installation checkpoint. We also summarized technical approach and responses for this type of instrument in outdoor conditions, through the record and comparison of environmental factors during the observation period. The results indicated that A10 absolute gravimeter can complete the measurement of the outdoor gravity points with high efficiency and high precision. The ICAG-2017 and repeatability verification ensured the credibility of reconstruction in gravity base network. We found that He-Ne laser-based two mode of frequency drifted and influenced by various factors such as temperature and pressure, but there was no major fluctuation in the center frequency during short period, and we recommend the metrological parameters should be regularly calibrated in the further. The observation error of each base point is mainly affected by environmental disturbances from station quality, human activities and emergencies, and there was a high correlation between measure errors and the temperature difference in air and inside instrument. The detailed analysis of parameter design, technical approach and influencing factors of the A10 absolute gravimeter given in this paper can provide important reference for the observation implementation of the same type of instrument in th
作者
王林松
马险
陈超
黎海龙
莫亚军
汪利民
柳一鸣
WANG LinSong;MA Xian;CHEN Chao;LI HaiLong;MO YaJun;WANG LiMin;LIU YiMing(Hubei Subsurface Multi-scale Imaging Key Laboratory, Institute of Geophysics and Geomatics, China University of Geosciences, Wuhan 430074, China;Three Gorges Research Center for Geo-hazard, Ministry of Education, China University of Geosciences, Wuhan 430074, China;Guangxi Geophysical Investigation Institute, Liuzhou Guangxi 545005, China)
出处
《地球物理学报》
SCIE
EI
CAS
CSCD
北大核心
2019年第5期1885-1897,共13页
Chinese Journal of Geophysics
基金
国家自然科学基金(41504065
41574070及41604060)
广西国土资源厅科技项目
中国地质大学(武汉)中央高校基本科研业务费优青项目联合资助
关键词
重力基点网
标定场
A10绝对重力
室外快速观测
国际比对
Gravity basic network
Calibration baselines
A10 absolute gravity
Outdoor fast measurement
International comparison
