希尔伯特—黄变换在地电阻率数据处理中的应用

希尔伯特—黄变换用于处理非线性非平稳信号,由经验模态分解和希尔伯特谱分析2部分组成。本文采用希尔伯特—黄变换方法,相继对大同地震台地电阻率月值数据和宝昌地震台地电阻率月值、整点值数据进行处理。结果显示:(1)大同、宝昌地震台地电阻率月值数据对应的Hilbert谱具有较高分辨率,高幅值在归一化频率0.05—0.15区间内呈"余弦"变化形态;(2)希尔伯特—黄变换在提取地电阻率异常变化、高频信息及去除噪声等方面效果较好,在未来地电资料处理中具有广泛的应用前景。

Hilbert-Huang transform and its application in earth resistivity data processing

Hilbert-Huang transform is a method for processing nonlinear and non-stationary signals. It is composed of empirical mode decomposition and Hilbert spectrum analysis. In this paper, earth resistivity monthly values recorded by Datong and Baochang seismic stations, earth resistivity hourly ones recorded by Baochang Seismic Station are processed by using Hilbert-Huang transform. It is very important to preprocess the raw data before analyzing the simulation signal with Hilbert-Huang transform. The pretreatment results directly affect the reliability of the results of Hilbert Huang Transformation. Hilbert spectrum of earth resistivity monthly values recorded by Datong and Baochang seismic stations has high resolution characteristics, whose high amplitude in the normalized frequency range of 0.05-0.15 presents "cosine" change shape. Hilbert Huang Transform is very good effect in the extraction of the high frequency information of abnormal change and the removal of noise of earth resistivity, and so on.