Three-Dimensional Electromagnetic Imaging of Porphyry Copper Deposits with MT and ZTEM Data

• Author / Creator

  Lee, Benjamin

• This thesis investigates the use of the airborne Z-Axis Tipper Electromagnetic (ZTEM) and ground-based magnetotelluric (MT) exploration techniques to image electrical resistivity contrasts associated with porphyry copper deposits. These techniques were individually used to construct three-dimensional (3-D) electrical resistivity models of the Morrison porphyry copper deposit that contain resistivity contrasts caused by hydrothermal alteration, faulting, and possibly sulfide mineralization. The MT resistivity model, which incorporated electric and magnetic field data, correlates very well with the ZTEM resistivity model which only used magnetic field data. 3-D joint ZTEM-MT inversions showed that with appropriate data weighting, the joint resistivity models contained shallow features from the ZTEM data as well as deeper structure required by the MT data. For deposits that require investigation below a depth of about 2 km, there is value in following up a ZTEM survey with a small-scale MT survey to constrain absolute resistivity values and to provide information about deeper structure.

• Subjects / Keywords

  • Geophysics
  • Mineral Exploration
  • Inversion
  • Magnetotellurics
  • Electromagnetics

• Graduation date

  Fall 2015

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R31R6N57H

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.