Use of DEVICO Deep Drilling Technology at Rory’s Knoll (Aurora Project), Guyana
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Transcript of Use of DEVICO Deep Drilling Technology at Rory’s Knoll (Aurora Project), Guyana
Use of DEVICO Deep Drilling Technology at Rory’s Knoll (Aurora
Project), Guyana
Guyana Goldfields Inc.
The Country - Guyana
The Country - Guyana
• Only English speaking country in South America
• British common law, secure tenure
• Highly literate population of 700,000
• Pro-mining government
• Largely unexplored by modern methods
• Long history of significant gold production
History of Gold Exploration in the Guianas
“Guiana is a Country that hath yet her Maidenhead…not opened for gold, the mines not broken with sledges…”
Sir Walter RaleighThe Discovery of the Large, Rich and
Beautiful Empire of Guiana, 1596
Sir Walter Raleigh
The Region
The Guiana Shield
Aurora Property, GeologyAurora Property, Geology
Geology after Bracewell, 1949
Caleb’s East & West
Gold Creek
Property LocationsProperty Locations
Aurora PropertyAurora Property
The Golden MileThe Golden Mile
Aurora Base Camp
Golden Mile Mineralized Zones Diamond Drill Holes
Rory’s Knoll Diamond Drill Holes
Why DEVICO ?
• Constraint of 100 m x 150 m steep (70-75 deg) NNW-plunging Tonalite dimensions
• Historical left turns and consistent hole shallowing when drilling westwards due to regional foliation trend (NW)
• Problems with multiple wedging operations by Orbit drilling personnel
• Uncontrolled hole direction-wise
North East view of drilling operationsGrid (10mX10m) for a 680m target.
4 pilot holes and 36 directional cuts
DEVICO Requirements
• Rig capacity on total drilled depth
• RPM/WOB control• Mud Pump Capacity:
Flow Rate- 55 l/min Pump pressure- 60 bar
• Drilling mud pressure gauge & flow meter
• Mud pump accummulator / compensator (minimize pressure/flow rate pulsation)
• NQ-sized inner core barrel overshot / drill pipe sub
Long Section 10700E
Showing Lithology (plus blue-colored Devico directional
holes)
Long Section 10700E
Showing Assay Composites
Long Section 10750E
Showing Lithology (plus blue-colored Devico directional
holes)
Long Section 10750E
Showing Assay Composites
Long Section 10800E
Showing Lithology (plus blue-colored Devico directional
holes)
Long Section 10800E
Showing Assay Composites
Horizontal Plan View (-800 mRL)
Horizontal Plan View (-1000 mRL)
Devico directional factors
• Lithology (e.g. Ash Tuff Sediments)
• Structures (e.g. fault/foliation)
• Drilling parameters (e.g. hole azimuth & inclination)
• Target cone of influence specs per midpoint Devico target (e.g. up/down/left/right)
• DEVICO limits (e.g. high torque ~ 1000 m)
Devico-Orbit operations
• Rig mechanical problems (e.g. pump; etc.)
• Devico tool specs (e.g. thrust bearing; inner tube; etc.)
• Orbit-Devico drilling operations (e.g procedural; controlled drilling; etc.)
• Spare parts logistics
3-D View of Rory’s Knoll Mineralization
showing 100 m x 150 m Tonalite
dimensions (looking North)
3-D View of Rory’s Knoll Mineralization
showing 100 m x 150 m Tonalite dimensions
(looking East)
Devico-Orbit hole statistics
• RKD-60 mother hole: 9 directional cuts– Wedged/Devico-directed completed holes:
• RKD-60DV1/60DV2/60DV3L/60DV4R/60DV5R/• RKD-63B/RKD-67B/RKD-72B
• RKD-62 mother hole: 10 directional cuts– Wedged/Devico-directed completed holes:
• RKD-62DV1L/62DV2R/RKD-64/RKD-66/RKD-69/RKD-71/RKD-73
• RKD-63B/RKD-67B/RKD-72B
• Abandoned holes: – RKD-61A/61B/61C/RKD-63A/67A/72A
Summary
• 85 % Devico-hit on Rory’s Knoll mineralized zones on 19 medium to deep directional cuts proving mineralization is “open at depth”
• Cost-savings per hole (instead of drilling holes from surface): ~ 45-50% (estimated)
• Successful directional cuts are mainly dependent on drilling operations’ personnel teamwork and still improving !!!
• Once good Devico techs are spotted and with proven directional performance; don’t let go of them !!!