作为地电场最重要的背景变化组成成分之一，地电场日变化普遍存在。本文选取中国大陆10个地电场台站观测数据，应用时序迭加和谐波分析方法，研究地电场日变化的时间域和空间域基本特征。地电场日变化大多呈现“两峰一谷”或“两谷一峰”的变化特征，日变化特征一年四季基本相同，但是幅度、相位略有差异。此外，利用地磁、地貌、电性结构等资料，对地电场日变化的复杂性及与空间电磁活动、地下电性结构及潮汐相关性进行分析，认为地电场日变化特征本质是受空间电磁活动和地下介质电性结构、水文、地质等因素共同作用的结果。

The diurnal variation of geoelectric field,as one of the most important components in the electric field is a common feature world widely. In this paper,we used the observation data of 9 geoelectric field stations in Chinese mainland,and applied the method of harmonic wave synthesis and temporal superposition. We then conducted statistical analysis on the basic feature of diurnal variation of geoelectric field in time and spatial domain. The data shows that the diurnal variation of geoelectric field mostly are in the types of "two peaks and one valley" or "two valleys and one peak",and the characteristic is basically same in whole year,even though the amplitude and phase are slightly different. We also analyzed the complexity of the diurnal variation of geoelectric field and the correlation of the electromagnetic activity,electrical structure and tide by using the geomagnetic,geomorphic and electrical structure data. We conclude that diurnal variation of geoelectric field mainly result from space electromagnetic activity and electricity structure of underground medium,and it is also influenced by hydrology,geology,and other factors.

P315

中国地震台网中心青年科技基金（QNJJ201917）、国家自然科学基金（41374080）共同资助