Fig. 9From: Improved shift-invariant sparse coding for noise attenuation of magnetotelluric dataApparent resistivity and phase curves of the station QH401504. The upper panels are apparent resistivity curves and the bottom panels are phase curves. The red curves denote the results obtained by all the raw data sets D1 and D2; the solid lines represent the results obtained using noise-free data set D2; the green curves stand for the results achieved by data sets D1 and D2, but is de-noised by our new methodBack to article page