Application of magnetic field correlation in remote reference magnetotelluric data processing
Zhang Gang1, Tuo Xianguo2, Wang Xuben3, Gao Song3, Ding Mingtao1
1. School of Environment and Resource, Southwest University of Science and Technology, Mianyang, Sichuan 621010, China; 2. Chengdu Geological Survey Center, China Geological Survey, Chengdu, Sichuan 643000, China; 3. Institute of Geophysics, Chengdu University of Technology, Chengdu, Sichuan 610059, China
Abstract：We discuss in this paper applications of magnetic field correlation in remote reference magnetotelluric processing.We first analyze the influences of remote reference magnetotelluric on sounding curves with different noise level at the base station.The following phenomena are found:a.The sounding curve quality with a low signal-noise ratio cannot be improved by conventional remote referen-ce magnetotelluric methods; b.Based on statis-tics of some magnetic survey data,there is a strong correlation among magnetic signals at sounding points with the maximum distance of 40 km in Panxi Area.On this basis,a magnetic field correlation method between base stations and the referen-ce stations using remote reference magnetotellu-ric data is proposed in order to screen out power spectra and eliminate the noise.Test results on experimental data and measured data prove the effectiveness and correctness of the proposed method,and show better effects than conventional remote reference magnetotelluric methods.
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