Print Email Facebook Twitter Denoising controlled-source electromagnetic data using least-squares inversion Title Denoising controlled-source electromagnetic data using least-squares inversion Author Yang, Yang (Central South University China; Shandong University) Li, Diquan (Central South University China) Tong, Tiegang (Central South University China) Zhang, D. (TU Delft ImPhys/Acoustical Wavefield Imaging) Zhou, Yatong (Hebei University of Technology) Chen, Yangkang (Zhejiang University) Date 2018-07-01 Abstract Strong noise is one of the toughest problems in the controlled-source electromagnetic (CSEM) method, which highly affects the quality of recorded data. The three main types of noise existing in CSEM data are periodic noise, Gaussian white noise, and nonperiodic noise, among which the nonperiodic noise is thought to be the most difficult to remove. We have developed a novel and effective method for removing such nonperiodic noise by formulating an inverse problem that is based on inverse discrete Fourier transform and several time windows in which only Gaussian white noise exists. These critical locations, which we call reconstruction locations, can be found by taking advantage of the continuous wavelet transform (CWT) and the temporal derivative of the scalogram generated by CWT. The coefficients of the nonperiodic noise are first estimated using the new least-squares method, and then they are subtracted from the coefficients of the raw data to produce denoised data. Together with the nonperiodic noise, we also remove Gaussian noise using the proposed method. We validate the methodology using real-world CSEM data. Subject ElectromagneticsLeast-squaresNoiseSignal processingWavelet To reference this document use: http://resolver.tudelft.nl/uuid:44a3f674-f8e0-4414-a92e-fe1dd7139f96 DOI https://doi.org/10.1190/geo2016-0659.1 ISSN 0016-8033 Source Geophysics, 83 (4), E229-E244 Part of collection Institutional Repository Document type journal article Rights © 2018 Yang Yang, Diquan Li, Tiegang Tong, D. Zhang, Yatong Zhou, Yangkang Chen Files PDF geo2016_0659.1_1.pdf 9.96 MB Close viewer /islandora/object/uuid:44a3f674-f8e0-4414-a92e-fe1dd7139f96/datastream/OBJ/view