1. Airborne Resistivity Mapping with Helicopter TEM: An Oil Sands Case Study S. Walker and J. Rudd, Aeroquest International Ltd. KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007

2. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Acknowledgements Husky Oil Doug Oldenburg, Scott Napier and Roman Shekhtman (UBC-GIF) Jim Henderson (AGL) Aeroquest International

3. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Outline Introduction Geologic Setting EM System Descriptions Qualitative Data Comparison Quantitative Comparison Conclusions

4. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Introduction Oil Sands prospect in Northern Alberta Test survey flown for Husky Oil Provided three lines of comparison data

5. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Geologic Setting Geologic Unit Resistivity (Ωm) Thickness (m) Overburden100’s0 – 200 Clearwater Formation 2-100 – 30 McMurray Formation 100 – 100050 – 100 Devonian Basement 1 – 1000N/A Glacial cover Shale Oil Sands Limestone with/without salt water

6. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 EM System Descriptions AeroTEM IV (Aeroquest) –Helicopter TEM 90 Hz, Triangular pulse, 190,000 Am 2 Z comp., 17 off-time gates (2.01 – 5.13 ms) GeoTEM (Fugro) –Fixed-wing TEM 30 Hz, Half-sine pulse, 690,00 Am 2 X comp., 14 off-time gates (4.58 – 15.59 ms) Resolve (Fugro) –Helicopter FEM 5 coplanar freq. (400, 1500, 6200, 25k, 100kHz)

7. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Qualitative Comparison Common first step Data or image based Focus on northern most line Line 1 Line 2 Line 3

8. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Features in Data Paleo-channel Depth to the Clearwater Surface detail Bird height variation Good first pass But… AeroTEM Z (nT/s) GeoTEM X (pV/m 2 ) CP Inphase (ppm) CP Quad (ppm)

9. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Spatial Resolution Detailed view of paleo-channel data Sampling Freq. Survey speed Effect of foot print Need to do something else… AeroTEM Z (nT/s) GeoTEM X (pV/m 2 ) CP Inphase (ppm) CP Quad (ppm)

10. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Quantitative Comparison Rigorous 1D EM Inversion What can we see and do we believe it? Focus on specific soundings (1, 2, 3)

11. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Inversion Algorithm EM1DFM and EM1DTM (UBC-GIF) Model: log(σ), layered earth model Data misfit –Chi squared, noise estimates important Model Norm –Flattest and smallest model Remember that solutions are non-unique!!

12. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Recovered Models (Stn 1) 10 Ωm ref. model20 Ωm ref. model

13. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Recovered Models (Stn 2) 10 Ωm ref. model20 Ωm ref. model

14. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Recovered Models (Stn 3) 10 Ωm ref. model20 Ωm ref. model

15. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Depth of Investigation Index Oldenburg and Li (1999) if R = 0: m 1 = m 2 –More reliable model as R → 1: m 1, m 2 → m 1ref, m 2ref –Less reliable model Apply to our models and take a look…

16. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Models with DOI Index (Stn 1) 10 Ωm ref. model20 Ωm ref. modelDOI Index

17. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Models with DOI Index (Stn 2) 10 Ωm ref. model20 Ωm ref. modelDOI Index

18. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Models with DOI Index (Stn 3) 10 Ωm ref. model20 Ωm ref. modelDOI Index

19. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Pseudo 2D Model (Line 1) Geologically interpretable DOI helps know when to stop

20. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Pseudo 3D Model

21. Airborne Resistivity Mapping with Helicopter TEM KEGS Symposium: Geophysical Contributions to New Discoveries Exploration ’07, Toronto, September 2007 Conclusions Helicopter TEM has worked well in the Oil Sands High spatial resolution Sensitive to both near surface and deep features Pseudo 3D models Start applying it in other areas