 W-18: A Working Guide to 3D Inversion Methods in Mining Geophysics SEG 2012 Annual Meeting Technical Program
Date: Friday, 9 November 2012
Time: 8:30 am – 4:00 pm
Location: Mandalay Bay Convention Center, Room: Breakers B
Organizer: Mark Shore
Through the support of the SEG Mining Committee
Description
Inversion methods are being used on an increasingly wide range of geophysical data sets including gravity and magnetics, resistivity, induced polarization and radar tomography. Improvements in processing power, memory and algorithms mean that increasingly large problems can be handled at increasingly fine resolution, and in three dimensions. Progress is also being made, albeit at a slower pace, in geologically- or geometrically-constrained methods in which known or inferred lithologies and associated physical parameters limit the range of available inversion solutions. The artificial constraints imposed by 1D and 2D inversion methods are being replaced by a new set of limitations, in large part the underdetermined nature of 3D inversions coupled with the well-known limitations of non-uniqueness (no, those limits never really went away…). Without a sound knowledge of both the strengths and weaknesses of inversion methods, geophysicists run the risk, as methods become more powerful and easier to use, of over-reliance on a technological "black box". This workshop will bring together a range of experts to present the basic mathematics and algorithms of inversion methods, both the current state of the art and future aspects as well as their limitations. A select number of detailed case histories will be examined in more detail, and more critically, than is typically done. The workshop is aimed at non-specialist geophysicists who work with the various data sets involved and who are in positions to perform or contract out inversion studies and to interpret the results. Schedule Nominal times: 8:30 am: Introduction and overview—Mark Shore, Magma Geosciences Inc. 8:45 am: Joint inversion using physical property constraints—Jiajia Sun* and Yaoguo Li, Center for Gravity, Electrical and Magnetic Studies, Colorado School of Mines 9:30 am: Constrained geophysical joint inversion on unstructured meshes—Peter Lelievre*, Angela Carter-McAuslan, Cassandra Tycholiz, and Colin Farquharson, Department of Earth Sciences, Memorial U of Newfoundland 10:15 am: Break 10:30 am: A dual-mesh approach for distributed and highly parallelizable 3D inversion of large scale airborne EM data sets—Dikun Yang* and Doug Oldenburg, Geophysical Inversion Facility, Earth and Ocean Sciences, U of British Columbia 11:15 am: Inversion of airborne electromagnetic data using adaptive mesh refinement—Eldad Haber*, Department of Mathematics and Earth and Ocean Science, U of British Columbia 12:00 pm: Break 1:00 pm: Inversion of magnetic data from remnant and induced sources—Robert Ellis* and Ian Macleod, Geosoft Inc.; Barry de Wet, Ivanhoe Australia Ltd. 1:45 pm: Practical aspects of large-scale 3D airborne EM inversion—Leif Cox*, Glenn Wilson, and Michael Zhdanov, TechnoImaging LLC. 2:30 pm: 3D data integration with inversion—Nigel Phillips*, Peter Fullagar, Peter Kowalczyk, and Stanislawa Hickey, Mira Geoscience Advanced Geophysicial Integration Centre | 
