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Presented by: Date: ‘X-ray Plunge Projection’ Understanding Structural Geology from Grade Data Jun Cowan 18 August, 2014
Presented by: Date:
‘X-ray Plunge Projection’ Understanding Structural Geology from Grade Data
Jun Cowan 18 August, 2014
Why is the determination of deposit-scale structural architecture so
important?
The Parable of the Discovery Channel
Far, far away, in a parallel universe
Far, far away, in a parallel universe
at an international conference
Far, far away, in a parallel universe
at an international conference
six mining consultants
Far, far away, in a parallel universe
at an international conference
six mining consultants
were having a drink.
Far, far away, in a parallel universe
at an international conference
six mining consultants
were having a drink.
They were from…
South Africa
South Africa France
South Africa France
USA
South Africa France
USA New Zealand
South Africa France
USA New Zealand
Canada
South Africa France
USA New Zealand
Canada &
Australia
They were discussing this new
Monograph 30 that was released by the
AusIMM
when suddenly…
The door burst open
The door burst open
and in rushes John Fann1,2,3,4,...8, a well-respected mining professional, all breathless
The door burst open
and in rushes John Fann1,2,3,4,...8, a well-respected mining professional, all breathless
“Guys, I need your help!”
he shouted
John then explained that his company
John then explained that his company
Anglo Asian
John then explained that his company
Anglo Asian
was in deep trouble.
John then explained that his company
Anglo Asian
was in deep trouble.
He then slapped a drawing down on the table…
He said…
He said… “I want you guys to analyse what is missing from this deposit, using your technical expertise”
He said… “I want you guys to analyse what is missing from this deposit, using your technical expertise “We have a sample here, but that’s all we know!”
sample
“We want to know..." What geometry? What orientation? What size?
sample
“We want to know..." What geometry? What orientation? What size?
sample
“We want to know..." What geometry? What orientation? What size?
sample
“We want to know..." What geometry? What orientation? What size?
sample
“We want to know..." What geometry? What orientation? What size? “…of the missing part of this deposit”
sample
“Work it out as a team, then present a solution to me tomorrow”
Then John1,2,3,4,...8 thanked everyone,
and rushed out of the room
“Work it out as a team, then present a solution to me tomorrow”
Then John1,2,3,4,...8 thanked everyone,
and rushed out of the room
to collect another Adjunct Professorship 9
South African:
South African: “RRRoit, this is an easy one…”
South African: Main directions of continuity
South African: Main directions of continuity
South African: Main directions of continuity Variography
South African: Main directions of continuity Variography So the solution is…
South African: Main directions of continuity Variography So the solution is…This
French woman:
French woman: “Tsk, tsk, tsk, Danny, Danny, you are so old fashioned!”
French woman: Multiple directions of continuity
French woman: Multiple directions of continuity
French woman: Multiple directions of continuity
French woman: Multiple directions of continuity Pluri-gaussian simulation
French woman: Multiple directions of continuity Pluri-gaussian simulation So the solution is…
French woman: Multiple directions of continuity Pluri-gaussian simulation So the solution is…This
American:
American: “’C’mon, we’re not back in the last century, y’all!”
American: “In America, we use pattern recognition”
American: “In America, we use pattern recognition” Obtain patterns from densely sampled areas
American: “In America, we use pattern recognition” Obtain patterns from densely sampled areas Multi-Point Statistics
American: “In America, we use pattern recognition” Obtain patterns from densely sampled areas So the solution is…
American: “In America, we use pattern recognition” Obtain patterns from densely sampled areas So the solution is…This
New Zealander:
New Zealander: “Two words” said the Kiwi…
New Zealander: “Two words” said the Kiwi… “Cane Toad”
New Zealander: “Two words” said the Kiwi… “Cane Toad” “What?” everyone asked.
New Zealander: “It’s our new Implucit Modilling software”
New Zealander: “It’s our new Implucit Modilling software” “Cane Toad kills all other software, Bro”, explained the Kiwi.
New Zealander: “Implucit Modilling with Cane Toad…lowers Rusk” said the Kiwi… “You can’t go wrong!” So the solution is…
New Zealander: “Implucit Modilling with Cane Toad…lowers Rusk” said the Kiwi… “You can’t go wrong!” So the solution is…Thus
Canadian:
Canadian: “I do apologise for being Canadian, eh, but perhaps we can all get along and reach a compromise?”
Canadian: Probabilities
Canadian: Probabilities What are the variations?
Canadian: Probabilities What are the variations? “So, Danny, this is one possible variation, but sorry, that’s not the only one”
Canadian: Probabilities What are the variations? “To see all the patterns, we need to use Conditional Simulation”
Canadian: Probabilities What are the variations? “Like this”
Canadian: Probabilities What are the variations? “and these…”
Canadian: Probabilities What are the variations? “and these…”
Canadian: Probabilities What are the variations? “and these…”
Canadian: Probabilities What are the variations? These are all probable…
Canadian: Probabilities What are the variations? These are all probable… Aren’t they, eh??
Then…
The Australian who had missed all this debate…
Then…
The Australian who had missed all this debate…
(because he was chatting up Betty at AusIMM booth)
Then…
The Australian who had missed all this debate…
(because he was chatting up Betty at AusIMM booth)
takes a glance at the picture on the table,
and said:
Australian: “This is a human skeleton”
Australian: “This is a human skeleton” Which means that there is only one answer!
Australian: “This is a human skeleton” Which means that there is only one answer! All other ‘solutions’ are not only improbable, but impossible…
Australian: “This is a human skeleton” Which means that there is only one answer! So the solution is…
Australian: “This is a human skeleton” Which means that there is only one answer! So the solution is…This
The five others were speechless.
The five others were speechless.
They stared at the Australian’s solution.
The five others were speechless.
They stared at the Australian’s solution.
Stared at the Australian.
The five others were speechless.
They stared at the Australian’s solution.
Stared at the Australian.
They started at each other,
The five others were speechless.
They stared at the Australian’s solution.
Stared at the Australian.
They started at each other,
and…
They burst into uncontrollable laughter!
“How ridiculous!” sputtered the French woman.
“How ridiculous!” sputtered the French woman. “Where did you get your education?
“How ridiculous!” sputtered the French woman. “Where did you get your education? “Adelaide?”
“How ridiculous!” sputtered the French woman. “Where did you get your education? “Adelaide?” “You’re pussed, Bro!”, said the New Zealander.
“How ridiculous!” sputtered the French woman. “Where did you get your education? “Adelaide?” “You’re pussed, Bro!”, said the New Zealander. “Yahh, where did you get this wild idea from?”, asked the South African.
The Australian
The Australian
Took a swig from his beer
The Australian
Took a swig from his beer
and replied
The Australian
Took a swig from his beer
and replied
“from the Discovery Channel”
He continued…
He continued…
“I saw a program about human anatomy last night”
He continued…
“I saw a program about human anatomy last night”
on the
He continued…
“I saw a program about human anatomy last night”
on the
The others thought the Australian’s solution
The others thought the Australian’s solution
was unsophisticated and not technical enough
The others thought the Australian’s solution
was unsophisticated and not technical enough
not quantitative…
The others thought the Australian’s solution
was unsophisticated and not technical enough
not quantitative…
and weird.
The others thought the Australian’s solution
was unsophisticated and not technical enough
not quantitative…
They couldn’t possibly charge enough for his simplistic model!
After some deliberation
After some deliberation
The other five professionals
After some deliberation
The other five professionals
chose to present the Canadian model.
After some deliberation
The other five professionals
chose to present the Canadian model.
They could charge a lot of money for simulation,
After some deliberation
The other five professionals
chose to present the Canadian model.
They could charge a lot of money for simulation,
and it was general enough to cover everyone’s asses.
But in this parallel universe…
But in this parallel universe… The general population had no idea of the human anatomy…
But in this parallel universe… The general population had no idea of the human anatomy… In this group, only the Australian knew
Because he watched the
Because he watched the
Everyone else, but the Australian
Everyone else, but the Australian Were uninformed.
Everyone else, but the Australian Were uninformed. So, what they saw effectively was not this,
Everyone else, but the Australian Were uninformed. So, what they saw effectively was not this, But this…
The End
Takeaway Lessons
Not knowing the first-order anatomy of the deposit is the greatest risk for any mining company.
Not knowing the first-order anatomy of the deposit is the greatest risk for any mining company.
Everything else, such as modelling methodology, is of
secondary importance.
Not knowing the first-order anatomy of the deposit is the greatest risk for any mining company.
Everything else, such as modelling methodology, is of
secondary importance.
Fancy maths, or software, will never cover-up your ignorance!
Not knowing the first-order anatomy of the deposit is the greatest risk for any mining company.
Everything else, such as modelling methodology, is of
secondary importance.
Fancy maths, or software, will never cover-up your ignorance!
The answer is usually right under your nose.
“In general, an ounce of geology is worth a pound of geostatistics; this may be disappointing to geostatisticians with no geological background.”
Harry Parker
“In general, an ounce of geology is worth a pound of geostatistics; this may be disappointing to geostatisticians with no geological background. Tough.”
Harry Parker
“In general, an ounce of geology is worth a pound of geostatistics; this may be disappointing to geostatisticians with no geological background. Tough.”
Harry Parker
structural
structural
“In general, an ounce of geology is worth a pound of geostatistics; this may be disappointing to geostatisticians with no geological background. Tough.”
Harry Parker
structural
structural
“In general, an ounce of geology is worth a pound of geostatistics; this may be disappointing to geostatisticians with no geological background. Tough.”
Harry Parker
structural
structural
Wouldn’t it be nice if we could just glance at a grade dataset
(like the Australian in the parable), and be able to
determine the structural style of any mineral deposit—at the
scale of the deposit?
100 yr old down-plunge projection was able to do this for maps.
100 yr old down-plunge projection was able to do this for maps.
X-ray plunge projection is able to do this for 3D assay datasets.
100 yr old down-plunge projection was able to do this for maps.
X-ray plunge projection is able to do this for 3D assay datasets.
Over 600 deposits analysed over 12 years
Down-plunge Projection
Maximum Intensity Projection (MIP)
Maximum Intensity Projection (MIP)
Plan View
X-ray Plunge Projection View
Easterly View
MIP
X-ray Plunge Projection View
Does Implicit Modelling Reduce Risk?
Does Implicit Modelling Reduce Risk?
Does Implicit Modelling Reduce Risk?
NO
Does Implicit Modelling Reduce Risk?
YES NO
Load drill holes Desurvey the assay data X-ray plunge projection of assay data points Interpret the results Model
Load drill holes Modelling by interpolation Interpret the interpolated results Remodel
GOOD LUCK!
Does Implicit Modelling Reduce Risk?
Does Implicit Modelling Reduce Risk?
NO, not without prior structural analysis using X-ray plunge projection
Does Implicit Modelling Reduce Risk?
NO, not without prior structural analysis using X-ray plunge projection
Ignore structural architecture, and Implicit Modelling will INCREASE risk
Three Steps:
1. Use X-ray to determine the Plunge direction of grade data. Only one view-direction makes sense.
Three Steps:
1. Use X-ray to determine the Plunge direction of grade data. Only one view-direction makes sense.
2. Comprehend the patterns in terms of structural style. Extensive field and theoretical experience in structural geology is necessary.
Three Steps:
1. Use X-ray to determine the Plunge direction of grade data. Only one view-direction makes sense.
2. Comprehend the patterns in terms of structural style. Extensive field and theoretical experience in structural geology is necessary.
3. Choose appropriate modelling method.
Education
Education
