报告题目：AEM interpretation with the sphere model
报 告 人：Dr. Marc A. Vallée and Mouhamed Moussaoui
报告时间：2021.11.4 at 9:00-10:30AM (Beijing time) or 21:00-22:30PM (Quebec time)
会议ID：312 139 480 会议链接：https://meeting.tencent.com/dm/bGZXht7iCOIe
Dr. Marc Vallée graduated in geological engineering from Laval University, before completing a master’s degree in geophysics at the University of Toronto, and a PhD in geophysics at École Polytechnique de Montréal. He has over 25 years of experience as a research scientist in applied geophysics, mainly for the Noranda Technology Center, then for the Fugro Airborne Surveys Company. Recently, he was responsible for geophysical inversion as part of the NSERC-CMIC Footprints project. His expertise is mainly in the processing and interpretation of electromagnetic, magnetics and airborne gravity surveys. He is the author of several scientific articles in applied geophysics.
Mr. Mouhamed Moussaoui has more than 30 years of experience in the supervision and execution of projects related to fixed-wing, helicopter, and ground geophysics. He has managed several mandates and has been involved in every stage of project execution. Mr. Moussaoui was project manager in most of the airborne mandates obtained by SIAL Geosciences Inc., then by Fugro Airborne Surveys Corp. at the Montreal office, which involves several million km-linear surveys. He founded Geo Data Solutions GDS Inc. in 2007 and is the president since.
Introduction to the presentation: Airborne Electromagnetic (AEM) data interpretation is a laborious process. Data noise and complexity of Maxwell’s equations make inversion process ill-constrained, and multiplicity of solutions are possible. An alternative is to use parametric models, such as a plate or a sphere. A sphere in free space is the oldest electromagnetic model. It can be integrated in a parametric inversion model and automated to handle survey interpretation. However, it won’t be appropriate in situations where overburden or/and host rock are conductive. To address this problem, we developed a solution for a sphere in a layered earth. For that purpose, we extended the use of spherical harmonic expansion to cylindrical harmonic expansions, which allows the computation of the various derivative required to provide a solution. Using this new model, we present synthetic responses and interpretation of field data collected over Reid-Mahaffy, Ontario, test site.