Premium
Modelling and inversion of electromagnetic data using an approximate plate model
Author(s) -
Pirttijärvi Markku,
Pietilä Risto,
Hattula Aimo,
Hjelt SvenErik
Publication year - 2002
Publication title -
geophysical prospecting
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.735
H-Index - 79
eISSN - 1365-2478
pISSN - 0016-8025
DOI - 10.1046/j.1365-2478.2002.00332.x
Subject(s) - computation , inversion (geology) , parametric statistics , computer science , algorithm , synthetic data , conductor , singular value decomposition , experimental data , mathematical optimization , geophysics , mathematics , geology , geometry , paleontology , statistics , structural basin
This paper presents a computational method for the interpretation of electromagnetic (EM) profile data in the frequency domain using a thin plate model within a two‐layer earth. The modelling method is based on an integral equation formulation, where the conductor is represented by a lattice structure composed of two‐dimensional surface elements. Several approximations are used to simplify the theoretical basis and to decrease the computation time. The simple parametric model allows efficient use of optimization methods. We employ a linearized inversion scheme based on singular value decomposition and adaptive damping. The new forward computation method and the parameter optimization are combined in the computer program, emplates . The modelling examples demonstrate that the approximate method is capable of describing the characteristic behaviour of the EM response of a thin plate‐like conductor in conductive surroundings. The efficacy of the inversion is demonstrated using both synthetic and field data. An optional depth compensation method is used to improve the interpreted values of the depth of burial. The results show that the method is cost effective and suitable for interactive interpretation of EM data.