Rapid and rigorous 3D inversion of airborne electromagnetic data
نویسندگان
چکیده
We address the challenging problem of interpreting frequency domain helicopter-borne electromagnetic data in areas with rough topography. Our method is based on localized quasi-linear (LQL) inversion followed by rigorous inversion, if necessary. Terrain corrections are also included. The LQL inversion serves to provide a fast image of the target. These results are checked by rigorous successive iterations of the domain equation, allowing more accurate calculation of the predicted data. If the accuracy is poorer than desired, rigorous inversion follows, using the LQL result as a starting model. We test this method on synthetic data and field data using the new code LQLRigInvTOPO. The results of the inversion are very encouraging with respect to both the speed and the accuracy of the algorithm. The numerical study shows that the new code with terrain correction provides a useful tool for airborne EM interpretation.
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