Three key points about imaging subsurface parameters between boreholes: 1. Downhole IP and resistivity tomography techniques provide more information than traditional drilling alone by assessing continuity of structures and detecting conductive zones between and around boreholes. 2. EarthProbe tools can map resistivity and chargeability between boreholes up to 250m apart, helping understand the subsurface. 3. New directional surface-to-borehole imaging provides directional information on zones between holes to improve drill targeting.

2. Technology for Imaging Key Vectoring Parameters
Between Boreholes
Applications of Downhole IP and Resistivity Tomography in Exploration Environments
Rob Gordon, MBA., P.Eng

3. Today’s Realities
• Complicated geologic situations
• Technology has improved - Sub- surface imaging is sophisticated
for resistivity
• Drilling returns only a small representative sample of the
subsurface
• More Key and Critical Information can be provided from drill holes

4. EarthProbe Improves the Search for Mineralization
• Assesses continuity of important structural and
geologically significant zones
• Detects conductive/chargeable zones in the
vicinity of a borehole
• Enables estimation of bulk
resistivity/chargeability characteristics
• Maps conductive/chargeable zones between
boreholes
• Surface IP offers high resolution for accurate
mapping of subsurface disturbances
Commodities
Gold
Nickel sulfides
VMS copper-zinc
Copper porphyry
PGE

5. Operational Modes
• Downhole IP
• Vertical Resistivity Profiling (VRP)
• Tomography
• Borehole-to-borehole
• Surface-to-borehole
• Surface IP
• 4.4 – 10 m station spacings
• Enhanced detection of structures
• Resolution of narrow targets
• Choice of electrode arrays
• Depth penetration up to 250 m

6. EarthProbe Borehole IP – 3 Configurations
Surface-to-BoreholeTomography
• 400 m depth
• 4 m spacing (100m probe) or 16 m spacing (400
m probe)
• Image between bores 100-250 m separation
• Water-filled boreholes required

7. Why it is better

8. Two drill holes can yield a significant amount of subsurface information when
between hole imaging is carried out. This can help the overall understanding of
the continuity of the subsurface
Resistivity DATA PANELS
between holes
EarthProbe Borehole Tomography

10. CHALLENGE
COSTLY BOREHOLE INTERSECTS ZONE OF INTEREST,
THE NEXT PRE-PLANNED DRILL PLAN DOES NOT
ACCOUNT FOR WHAT HAS BEEN DISCOVERED IN
THIS HOLE WITH RESPECT TO DIRECTION OF FLOW.
SOLUTION
NEW – DIRECTIONAL SURFACE TO BOREHOLE
IMAGING CAN PROVIDE DIRECTIONAL
INFORMATION ON ZONES TO HELP TUNE DRILL
PROGRAMS.

11. DIRECTIONAL DEPTH SLICE
PROVIDES DIRECTIONAL INFORMATION ON KEY ZONES OR STRUCTURES

12. Portable

13. EarthProbe Provides Useful Information
Surface Resistivity
• Deep penetration (up to 200m)
• High lateral resolution
Borehole
• More functional than historic methods of achieving downhole information
• Tomographic capability enables imaging between bores
Integrated surface and borehole measurements
Flexibility for surveying in difficult environments
Contact: geophysics@caraclecreek.com