洱源台观测环境条件变化对形变观测数据的影响

Influence of Changes in Surrounding Environment on the Crustal Deformation Data at the Eryuan Seismic Station

2007-2019年洱源台洞体应变及辅助硐室温度的长期观测数据中存在明显的分段特征,通过多测项数据对比、日志追踪、现场调查等方法分析查找导致数据分段的近场环境事件。结果表明:近场环境的某些细微变化能够引起形变观测数据振幅、频率、组分、稳定性的变化,导致前后数据的不一致,从而影响观测数据的稳定性。因此,必须尽可能保持近场环境恒久不变以确保观测数据的长期稳定性,从而避免前后数据可比性降低影响前兆数据在中短期地震预测中的应用价值。

In the long-term crustal deformation data and geothermal temperature data from 2007 to 2019 in the Eryuan seismic station,the segmentation characteristics are obvious.For finding the reasons which cause the segmentation,methods of multi-data comparing,daily record scanning,and field surveying are used to look for near field changes in surrounding environment.The result is given that some small changes in near field environment can lead to terrible changes of observation data in some aspects such as amplitude,frequency,composition,and stability.Then the long term data is inconsistency and instability.It is argued that the near-field environment should be kept to ensure the stability and consistency of observation data.Then the long-term data can be used in medium and short term earthquake prediction.