....... This is what I have read not what I know!
As part of exploration legislation, drilling companies are required to cap off/cover drill holes to prevent wildlife entering when the hole is completed. If there has been no seismic activity and the holes are intact, then before carrying out further drilling, down hole surveys would be carried out to determine position relative to north, alteration, magnetic and mineral direction..
So in the case of Earnest Giles and other tenement existing holes would most likely be surveyed first with the latest technology before drilling further holes where possible.
https://coringmagazine.com/article/devi ... rvey-tool/
"A DDH1 drill site in Western Australia. Namely, a 2410-meter deep, near-vertical hole, with seven significant directional cuts to aim the hole to target. DDH1 are renowned for accuracy in deep hole directional drilling,"
https://downhole.com.au/
Drilling Strategy cost overlooked
-
HopefullyGold
- Reactions:
- Posts: 70
- Joined: Tue Jun 28, 2022 7:03 am
-
Guy Shelby
- Reactions:
- Posts: 19
- Joined: Fri Feb 14, 2025 11:40 pm
Re: Drilling Strategy cost overlooked
Some info on the types of drilling that has currently been stepped up with additional rigs deployed.
Newmont had at one point I can recall, having 9 drill rigs operational , just on Havieron. So it is understandable that even more rigs will be even further deployed at Telfer, particularly as WDD can be better accessed underground and with an ever increasing resource elsewhere. It is necessary to drill these out like a pin cushion to be confident of bringing them into a robust mine plan. They don’t come cheap.
Typical costs for diamond core for instance ‘per metre,’ range from A$100 - A$300 depending on core size and environment. which doesn’t include the geo team analysis, assays, modelling environmental reinstatement etc, just drilling. So they are looking at average of over £100,000 or A$200,000+ for just ‘one’ deeper hole.
Drilling for resource definition and
grade control typically includes a combination of surface reverse circulation (RC) and surface and underground diamond (DD) drilling. Generally are carried out throughout the mines life
Core sizes for resource or exploration drilling, usually range from NQ up to PQ, while grade control drilling is generally carried out with smaller core sizes, such as the most common NQ which is often preferred for grade control as it provides a good balance between core recovery and sample quality. Smaller size BQT is often used where access is limited
Diamond drilling sample lengths range from 1.2 metres down to a minimum of around 0. Although 1 metre intervals are most common. NQ and larger cores are typically cut and half-sampled (with half retained), while smaller cores are often sampled whole.
RC drilling samples are usually collected at 1 metre intervals but can sometimes vary to 2 metres. These are split using a riffle or cone splitter attached to the drill rig cyclone, producing a 2 to 5 kg primary sample. The bulk reject from splitting is retained in numbered bags for temporary storage and logging.
Rock chip samples can also be taken manually using geo-picks, from the exposed mine face.
Exploration/Resource definition core sizes-
PQ: Approximately 85 mm (3.35 inches) in diameter. This size is often used for larger diameter holes and is suitable for obtaining high-quality core samples.
HQ: Approximately 63.5 mm (2.5 inches) in diameter. This is a widely used size for exploration drilling and is suitable for a variety of geological conditions.
NQ: Approximately 47.6 mm (1.87 inches) in diameter. This size is often used for deeper drilling and in harder rock formations.
BQ: Approximately 36.5 mm (1.44 inches) in diameter. This smaller size is used in specific situations where access is limited or for detailed geological studies.
AX: Approximately 30 mm (1.18 inches) in diameter. This is less common but may be used for specialized applications.
Grade control driling.
NQ: Approximately 47.6 mm (1.87 inches) in diameter. This size is often preferred for grade control as it provides a good balance between core recovery and sample quality.
HQ: Approximately 63.5 mm (2.5 inches) in diameter. While less common than NQ for grade control, HQ can be used in certain situations where more material is needed for analysis.
BQT: Approximately 36.5 mm (1.44 inches) in diameter. This size may also be used in specific grade control applications, particularly in areas where access is limited or for more detailed sampling.
Newmont had at one point I can recall, having 9 drill rigs operational , just on Havieron. So it is understandable that even more rigs will be even further deployed at Telfer, particularly as WDD can be better accessed underground and with an ever increasing resource elsewhere. It is necessary to drill these out like a pin cushion to be confident of bringing them into a robust mine plan. They don’t come cheap.
Typical costs for diamond core for instance ‘per metre,’ range from A$100 - A$300 depending on core size and environment. which doesn’t include the geo team analysis, assays, modelling environmental reinstatement etc, just drilling. So they are looking at average of over £100,000 or A$200,000+ for just ‘one’ deeper hole.
Drilling for resource definition and
grade control typically includes a combination of surface reverse circulation (RC) and surface and underground diamond (DD) drilling. Generally are carried out throughout the mines life
Core sizes for resource or exploration drilling, usually range from NQ up to PQ, while grade control drilling is generally carried out with smaller core sizes, such as the most common NQ which is often preferred for grade control as it provides a good balance between core recovery and sample quality. Smaller size BQT is often used where access is limited
Diamond drilling sample lengths range from 1.2 metres down to a minimum of around 0. Although 1 metre intervals are most common. NQ and larger cores are typically cut and half-sampled (with half retained), while smaller cores are often sampled whole.
RC drilling samples are usually collected at 1 metre intervals but can sometimes vary to 2 metres. These are split using a riffle or cone splitter attached to the drill rig cyclone, producing a 2 to 5 kg primary sample. The bulk reject from splitting is retained in numbered bags for temporary storage and logging.
Rock chip samples can also be taken manually using geo-picks, from the exposed mine face.
Exploration/Resource definition core sizes-
PQ: Approximately 85 mm (3.35 inches) in diameter. This size is often used for larger diameter holes and is suitable for obtaining high-quality core samples.
HQ: Approximately 63.5 mm (2.5 inches) in diameter. This is a widely used size for exploration drilling and is suitable for a variety of geological conditions.
NQ: Approximately 47.6 mm (1.87 inches) in diameter. This size is often used for deeper drilling and in harder rock formations.
BQ: Approximately 36.5 mm (1.44 inches) in diameter. This smaller size is used in specific situations where access is limited or for detailed geological studies.
AX: Approximately 30 mm (1.18 inches) in diameter. This is less common but may be used for specialized applications.
Grade control driling.
NQ: Approximately 47.6 mm (1.87 inches) in diameter. This size is often preferred for grade control as it provides a good balance between core recovery and sample quality.
HQ: Approximately 63.5 mm (2.5 inches) in diameter. While less common than NQ for grade control, HQ can be used in certain situations where more material is needed for analysis.
BQT: Approximately 36.5 mm (1.44 inches) in diameter. This size may also be used in specific grade control applications, particularly in areas where access is limited or for more detailed sampling.