hal-01458151
https://brgm.hal.science/hal-01458151
https://brgm.hal.science/hal-01458151/document
https://brgm.hal.science/hal-01458151/file/Bretaudeau-2017-EM3D-6-Berkeley.pdf
[BRGM] Bureau de Recherches Géologiques et Minières
[INSMI] CNRS-INSMI - INstitut des Sciences Mathématiques et de leurs Interactions
[OPENAIRE] OpenAIRE
[GENCI] GENCI
[TDS-MACS] Réseau de recherche en Théorie des Systèmes Distribués, Modélisation, Analyse et Contrôle des Systèmes
3D land CSEM inversion in noisy environment with a single transmiter: inversion approach and application for geothermal water prospection
Bretaudeau, François
Penz, Sebastien
Coppo, Nicolas
Wawrzyniak, Pierre
Darnet, Mathieu
[PHYS.PHYS.PHYS-GEO-PH] Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph]
[MATH.MATH-OC] Mathematics [math]/Optimization and Control [math.OC]
COMM
3D inversion
land CSEM
noisy environment
single transmiter
sensitivity singularities
thermal water prospection
Anthropogenic noise, cost and logistical constrains generaly limit to the use of land CSEM to a few transmiter positions for the deep imaging of the electrical conductivity. The 3D inversion of CSEM data in the near field using a single transmiter position suffers from critical sensitivity singularities. We proposed a robust inversion framework adapted to this ill-conditioned inversion problem. The framework relies specificaly on a robust Gauss-Newton solver, model parameter transformations to compensate the heterogeneous sensitivies, and on the reformulation of the near field CSEM data under the form of a pseudo-MT tensor. We describe the approach used for modeling and inversion implemented in our code POLYEM3D and show the advantages of pseudo-MT tensor formulation. The strategy have been tested on a pathologic synthetic case inspired from grayver et al (2013), and then was successfully applied to a real CSEM dataset acquired in the context of thermal water prospection in a noisy environnement.
2017-03-28
2017-02-06
en
International Symposium in Three-Dimensional Electromagnetics (3DEM)
Berkeley, United States