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Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
ExplorationDrilling Techniques
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
Why do we need natural resources?
average increase in demand: 5 % per year
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
How do we find new resources?
“In my view the greatest value is added by the geologist who starts with nothing other than some ideas and goes out into the desert and finds an orebody.”
J.K. Ellis, Chairman of BHP, Australia 1998
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
How do we find new resources?Fun!
Reality is: hard work!
Geological methods:
• Systematic exploration of larger areas
• Exploration in geological environment found to be similar to known deposits
• Improved geological interpretation and analysis of existing data
• Development of exploration model based on geological, geochemical and geophysical parameters
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
How do we find new resources? Pre-study
Reconnaissance exploration
Detailed follow-up exploration
Evaluation
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
How do we find new resources?
• What is beneath our feet?
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Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
Example:
Geothermal Energy Project St. Gallen
Pre-study:
Seismic Field Campaign
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
Example:
Geothermal Energy Project St. Gallen
Pre-study:
Interpretation of seismic measurements
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
Example:
Geothermal Energy Project St. Gallen
Exploration:
Start of drilling: Monday March 4, 2013
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingRotary drilling
• Oil field rig
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
Drilling1. Mud tank
4. Mud pump
7. Winch
14. Derrick/mast
16. Drill rods
20. Rotary table
23./24. BOP
26. Drill bit
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingRotary drilling
• Deep water wells(Palestine)
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Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingRotary drilling
• Rotary table with opening for the “kelly”
• Drive mechanism
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingRotary drilling
• Drill bit (Trycone)
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingRotary drilling –
Some details
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingRotary drilling
• Modern drill rig for deep drilling
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingSchematic sketch of modern drill rig for deep drilling
• Top drive instead of rotary table
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
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Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingRotary drilling
• Pipe handler
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
chute with1,5% incline
300m³/h
2mm
300m³/h
0,10mm
0,10mm
0,10mm
M M
0,02mm
15m³/hM M
0,02mm
15m³/h
M M M
M M M
250m³/h
250m³/h
100m³/h
100m³/h
100m³/h
DrillingRotary drilling
• Mud flow
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingRotary drilling
• Spindle drive
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingRotary drilling
• Spindle drive
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingRotary drilling
• …no need to be verybig!
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingMud flow in borehole
• Pumped down the drill string
• Raises in the annulus
• Cooling of the drill bit
• Carries the cuttings to the surface
• Prevents from blocking the string (thixotropy)
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Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingDirectional drilling
http://www.sbo.at/cms/cms.php?pageName=61&movieQuality=hq&sid=4403c274e1c7f695bfe7557383878f36
• The drill string becomes flexible when drilling very deep boreholes direction cannot be maintained
• A downhole motor (positive displacement motor PDM) is used for driving the drill bit
• The mud flow drives the PDM
• MWD (measurement while drilling) allows continuous directional control of the drill bit
• Allows drilling of several wells from 1 drill site (most often applied in off-shore drilling)
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingReverse Circulation(RC)
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
• A pneumatic reciprocating piston (hammer) drives the a tungsten-steel drill bit
• Working with large air compressors, the drilling produces dry rock cuttings
• Dual wall drill rods are used to inject air and to produce cuttings through the drill string
• Air is blown down the rods (annular space) and air, water and cuttings are lifted inside the inner tube
• Air passes through a cyclone for separation of cuttings
DrillingReverse Circulation(RC)
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingReverse Circulation(RC)
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingReverse Circulation(RC)
• Iron ore exploration(Western Australia)
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingDown-the-hole-hammer drilling (also Rotary Air Blast drilling – RAB)
• Pneumatically reciprocating piston-driven hammer
• Cuttings raise in the annulus
• Efficient drilling technique
• Used in exploration, blast-hole drilling, water wells, geotechnics
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Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingDown-the-hole-hammer drilling (also Rotary Air Blast drilling – RAB)
• Commonly used drilling technique for ground heat pumps
• Depth is limited by maximum pressure of compressor
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingAuger drilling
• Drilling in unconsolidated ground, in soil or in weathered rock
• e.g. for bauxite exploration
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingDiamond core drilling
• Wireline core drilling (gold exploration , Quebec, Canada)
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
Drilling
Diamond core drilling
• Drill core “growths” inside inner tube
• Retrieve the entire drill string to recover inner tube with the core
• Core lifter case at bottom end of inner tube prevents the core from falling out
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingDiamond core drilling
• Wireline core drilling (iron ore exploration , Cameroon)
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingDiamond core drilling
• Drill bits for diamondcoring
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Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
Wireline coring
• Drill core “grows” inside inner tube
• A overshot tool is lowered on the wireline to unlatch the inner tube from the core barrel
• Retrieve the inner tube with the core
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
Wireline coring
• Inner tube with latch head
• Overshot tool
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
Wireline coring
• Inner tube
• Overshot tool
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingDiamond core drilling
• Drill cores in core boxes
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingLarge diameter drilling
• Accident in Mina San JoséAugust 5, 2010
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingLarge diameter drilling
• Raise bore technique
1. Drilling of a pilot hole
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Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingLarge diameter drilling
• Raise bore technique
2. Drilling of a shaft
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingLarge diameter drilling
• Raise bore machine
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingLarge diameter drilling
• Raise bore head
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingLarge diameter drilling
• Down-bore technique
Shaft sinking from top
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingLarge diameter drilling
• Rescue of Chilean miners
Applied Mineralogy and Non-Metallic Resources I Exploration/Drilling
DrillingLarge diameter drilling
• Rescue of Chilean miners after 69 daysOctober 13, 2010