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Geometry of Kimberlites
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Transcript of Geometry of Kimberlites
“Geometry of Kimberlites” by Igor Kryvoshlyk
Universal
Kimberlite
Exploration
System
Preface
World Supply and Demand
for Rough Diamonds
Production and Demand for Rough Diamonds
Source: WWW Forecasts Ltd
Production
Demand
2003 2005 2007 2009 2011 2013 2015 2017 2019 2021 2023 2025
$60bn
$50bn
$40bn
$30bn
$20bn
$10bn
$0bn
Rough and Polished Prices
WWW Diamond Forecasts Limited
WWW Overall Rough Index
Polished Prices Overall Index
2002 2003 2004 2005 2006 2007 2008 2009 2010 2011
240
230220
210
200
190
180
170160
150
140
130
120
110
100
90
Content
• Part 1. Continents
• Part 2. Kimberlite provinces
• Part 3. Kimberlite clusters
• Part 4. Geochemistry of kimberlites
• Part 5. Mathematical calculations of
kimberlite diamond grade
Geometry of Kimberlites
Part 1:
Continents
Cratons are the best areas for exploration for diamonds. However, cratons are huge. How to find the next diamond mine?What is the law of distribution of diamond mines on the Earth?
Worldwide distribution of kimberlitesis not random (equatorial projection)
White Sea
Yakutia
NWT
Major kimberlite provinces of Northern Hemisphere
(polar projection)
North Pole
Alaska – the northernmostpoint of the Pacific Rim
Iceland
Major volcanic provinces of Northern Hemisphere(polar projection)
North Pole
There is a clear pentagonalsymmetry within Northern Hemisphere: all five occurrences located at the same distance from North Pole and at the Arctic Circle.
Symmetry is a law of geometry
Axis of symmetryArctic Circle
Plane of symmetry
North Pole
Pentagonal symmetry can be found in the alive nature only. Crystalography does not recognize
pentagonal symmetry
Apple shows pentamerism Starfish
Tetragonal symmetry in Southern Hemisphere
BrazilSouth Pacific – the southernmost
point of Pacific Rim
Australia Southern Africa
Antarctica,South Pole
Plane of symmetrywhich connects North and South
Tropic of Capricornmakes 90 deg.angle withArctic Circle
Tetragonal symmetry can be found in both: in minerals and in alive nature
Vesuvianite from Jeffrey Mine, Québec, Canada Alliaria Petiolata
Kimberlite/volcanic provinces of the Earth(Polar projection of both hemispheres on transparent globe)
Arctic Circle (upper red line), Tropic of Capricorn (lower red line), plane of symmetry (red broken line) and major volcanic / kimberlite provinces of the Earth (stars).
Equatorial projection of both hemispheres
Provinces and Sub-ProvincesPerfect octahedral diamond crystals from the central
part of the Yakutian kimberlite province (Mir kimberlite, Russia), and opaque cubic diamonds from
the Central African kimberlite sub-province (Mbuji Mayi, Zaire).
Diamonds from Mir pipe Diamonds from Mbuji-Mayi
Geometry of
Kimberlites
Part 2:
Kimberlite Provinces
Does the law of distribution of kimberlites exist?
(Southern Africa)
Geomorphologic ring structures of the Earth
After: Dr. Gavrilov, Vladivostok, Russia, 1977
The “Spiderweb”: ring complexes of Southern Africa
Radiuses of rings of each ring complex create a mathematical progression. All major diamond mines are located inside the intersections of the rings.
Mbuji-Mayi kimberlite polygon
0 00
00
0 0
0
0
Mbuji-Mayi
Oliphant's MineWimbledon Mine
Paardeberg Central
Paardeberg East MK1(10 cpht)
Pole MineVictoria MineMay (Phoenix) MineGood-Bad Hope
Gannavlakte
Loxton's Dal Diamond Mine (7 cpht)
Aaron's Prospect
Kamfersdam Mine (28 cpht)
SecretarisOtto's Kopje Mine (5 cpht)
De Beers Mine (80 cpht)Dutoitspan Mine (36 cpht)
Speculatie
Blow-1
Kimberley group of mines
TR-107
T-7N
A154-South (310 cpht)
C13
A10
T-29 T-19T-17T-16
C-49
T-14
A-61 T-146
A-27
A-25
A-44
T-33
C-27
AD02DO-18
DO-40 (Barren)
DI-02
DD-17DD-42 EG-01 (Very Low)
Don Finlay
Hardy Lake
Hardy Lake
GeorgeAnne
Falcon (28 cpht)
Fox (26 cpht)
Grizzly
Leslie (40 cpht)
Point Lake (56 cpht)
Hawk - Willy
Sable (98 cpht)
Jay (201 cpht)
CaribouKaska
Rufus
Wombat
Rat
DolphinPorpoise
Elk
Mustang
Zebra
Boa
Black Spruce
Lynx (83 cpht)
Aaron
Jaeger
Husky
Afridi
Providence
A-4
Ekati and Diavik diamond mines
“Shattered Glass” structure:
Triple intersection (blue circle) is a mechanically weakest point for penetration of kimberlite magma and generation of diamonds
news.povray.org/.../
Simplified sketch of a combination of three ring/conical complexes (left). Red rhombs
indicate the best areas for exploration for kimberlite diamonds (<10%).
Vertical cross-section of a
single conical complex
Center of tectonic –
magmatic activityOut of scale
Barren areas
Diamondiferousareas
Blindzone
Selection of the best diamond exploration areas
(practical application of the “Spiderweb”)
Four exploration polygons within NWT, Canada, indicate location of the deep fault (black broken line)
Angola: Az= Somali-Mozambique Shield
Rhodesi-Transvaal Shield
Green Zone - for kimberlites with Diamond Grade between 10 - 30 cpht
Karoo-Kalahari PlateCape Fold Belt
RSA: Az= E.S.E.97Bushmen Shield
Tanzania: Az. =
Malagarasi Plate
Sahara Plate
Kasai-Angola Shield
Congo Plate
West Congolese Mobile Belt
Central African Shield
Niger-Ahaggar Shield
Taudeni PlateRichat Ring Structure
West-African Shield
Okawango Plate
Mitoumba - Damara Fold Belt
Namibia: Az.= N.E. 50
Ring complexes of the African continent
Center of each ring complex is located on the border between major tectonic elements of the continent. Tectonic map after Trofimov V.S.
Eye of Africa – Richat structure, Mauritania – possible center of the conical complex
The structure has a diameter of almost 50 kilometres
(30 miles). Satellite image. NASA
Ring structure, Jebel Uwaynat, Sudan / Egypt / Libya – the next possible center
Satellite image. NASA
Geometry of Kimberlites
Part 3
Kimberlite Clusters
Distribution of diamond grade on the Earth
Northern Ontario, Canada.
High > 30 cpht
Moderate 10-30 cpht
Low < 10 cpht
Diamond Potential
Kimberlites with different diamond
grade NWT, Canada
Depth slice at 111 km of the 3-D resistivity model of the Slave craton.
Kimberlite diamond grade
Gibeon province, Namibia
After J.M. Batumike et al, 2008
Geometry of Kimberlites
Part 4
Geochemistry of kimberlites
Garnet Geochemical Chart
Ign. ECL
Metam. ECL
PYR
Majorites
Megacrysts
Kimberlite Field
Non-kimberlite Field
Depth: Pressure and Temperature
Y
X
Mantle – crust border
Orangegarnets
Purplegarnets
Redgarnets
A two-D projection of the nine-dimensional space
Metas. ECL
Grospydites
Geochemical chart for pyropes
Kimberlite pipes from the pink field on the map are located within the pink field (1) of the geochemical chart. Green field on the map corresponds with green field (2) of this chart. Blue field (3) – with blue
Y
X
Field 3. G < 10
Field 2. G = 10-30
Field 1. G > 30
Mathematical calculationsof kimberlite diamond grade
Geometry of Kimberlites
Part 5
Significance of the Correct Diamond Grade Data (Some historical quotations)
1) “The Tli Kwi Cho (DO-27) fiasco”: The Northern Miner. 10/26/1998
2) “Tli Kwi Cho diamond pipe was discovered in 1993 and bulk sampled in 1994. Based on limited disclosures the market developed high expectations that were shattered when the bulk sample results were released. Overnight nearly a billion dollars in market capitalization evaporated as investors abandoned diamond companies.” “Angry investors claiming that the analyst and his clients had an unfair advantage.” John Kaiser, July 10, 2001.
3) “Well known grade disasters like Tli Kwi Cho, Torrie, Torngat and Wawa”:Kaiser Express 2002-04, “The Northern Miner” March 22, 2002
4) “Kennecott’s NWT, Tli Kwi Cho failure causes large sell-off of diamond stocks.”: James Dartnell, “Anatomy of a stock market winner”, 2003.
5) The bulk sampling of the DO-27 pipe in 1994 “did not produce the anticipated high grades, led to a catastrophic Canadian junior stock market crash and abandonment of the project”: Coopersmith, H., Pell, J., and Scott Smith, B., 2006.
Evolution of Geological Models
Kimberlite Estimated Diamond Grade (feasibility study)(cpht)
Recovered Grade
Calculated Grade
MarsfonteinSouth Africa
335 308 242
Randgold Explor. 7th IKC S.Collingridge
Press Release Small Mines Wordsmith 1998 1998 1999
148.58SoutherneraAnn. Report
2000
149.44200 PYR5 ECL-17 ECL-3
UdachnayaRussia
120 100 Miller, P. “Diamonds” First Strike Yorkton Sec., 1995 Diamonds Inc.
60Eberle, J.M.
2003
65.99216 PYR
Kimberley“Big Hole”
South Africa
100 15 Moon, C.J. Grizzly Diamonds 2006 2007
63.88
Generic Template Diamonds of
Africa
64.23241 PYR
Finsch South Africa
80 49.30 43.99 before 1995 1995 Petra Diamonds Porter Geoconsultancy
36.33DBCM Report
2009
38.6173 PYR
VictorCanada
10 23 38 30.22 Winzar, DJ, P.Gregory Worldwide De BeersReport 2001 Report Diam.Update 2008 2004 2004
No Data 41.53
136 PYR
DO-27Canada
1.3 1 36…89.88 L.Rombouts Boxer, G.L.1994 Peregrine Diamonds 1994 “Microdiamonds” 2005
No Data 71.42
58 PYR
Why these numbers are so different? Why these numbers are so close?
Notes for the previous slide
There is a principal question for the feasibility study
results:
Why this feasibility study produced different data for the same kimberlite? Who is guilty for this, who is wrong?
Suggestion:
1. Feasibility study was conducted by perfectly trained professionals with B.Sc, M.Sc, Ph.D, P.Geo, P.Eng, P.Geol diplomas. Each of them is a QA/QC and Qualified Person
2. They did their job in complete accordance with all rules and regulations which described by the National Instrument NI43-101.
3. Nobody is guilty, nobody is wrong. The System is wrong.
# Kimberlite [reference]
Country, region
Predicted grade (cpht)
Final mining data, (cpht)
1 Marsfontein,M-1 [43] S. Africa 149.44 = 148.58 [4]
2 Klipspringer S. Africa 44.20 = 42.00 [5]
3 Kimberley “Big Hole” S. Africa 64.23 = 63.80 [6]
4 Finsch [34] S. Africa 38.61 = 36.33 [33]
5 Roberts Victor [47] S. Africa 132.99 > 100.00 [8]
6 Catoca [40]
Angola 57.14 = 58.00 [64, 65]
7 Camafuca [7] Angola 6.72 = 5.84 [68]
8 K-14 [14] Canada 12.46 ~ 12.00 [26]
9 Mir [40] Russia 96.93 ~ 100.00 [40]
10 Aikhal [37] Russia 91.01 ~ 100.00 [66]
11 Udachnaya [15] Russia 65.99 ~ 60.00 [16]
12 Zarnitsa [15] Russia 17.52 ~ 15.00 [67]
13 Sytykanskaya [15] Russia 66.79 ~ 60.00 [17]
14 Lomonosova [38] Russia 75.85 = 70.00 [27]
15 Ellendale-4 [56] Australia 5.78 = 5.1 [57]16 Garnet Lake [48-49] Greenland 107.37 ~ 100 [50]
Predicted Grade ~ Mining Data
Diamond grade (in cpht) must coincide with geographical location of kimberlite and also with its location on the geochemical chart
Victor kimberlite (G > 30 cpht) is located within pink rectangle on topographic map (left) and also within pink area on geochemical chart (right)
Triple-check of results:
Geochemical chart for pyropes
Kimberlite pipes f rom the red fi eld on the map are located within the red field (1) of the geochemical chart. Green fi eld on the map corresponds with green fi eld (2) of this chart. Blue fi elds (3) – the same
Y
X
Field 3. G < 10
Field 2. G = 10-30
Field 1. G > 30
High > 30 cpht
Moderate 10-30 cpht
Low < 10 cpht
Diamond Potential
Igor Kryvoshlyk joined SouthernEra Resources Limited in May 1995 as a mineralogist… During… more than 10 year period with SouthernEra, Igor spent most of his time doing microscope examination…His sorting of various kimberlitic minerals was always meticulously done, despite this being a painstaking task…
Igor is the only person I have known in all my years of kimberlite exploration, who is able to distinguish, with a high degree of certainty, optically and before probe analysis, between kimberlitic and non kimberlitic chromites and ilmenites. Similarly, he has an uncanny ability to distinguish eclogitic garnets from other, similar coloured garnets…
During his stay with us, Igor spent a lot of time collecting data for a huge database of kimberlitic mineral electron probe analyses. He spent a lot of time building research models from this data for the prediction of the location of kimberlites and predicting economic viability and even prediction of the grade of kimberlites from his mineral database…
Igor has a lively and enquiring mind and I had many interesting discussions with him, where he was often prepared to buck conventional wisdom and propose new and sometimes radical ideas. An attribute I greatly admire…
Dr. Christopher Mark Hubert Jennings.Chairman and former President and CEO SouthernEra Diamonds Inc. January 4, 2006.
About the Author
Igor Kryvoshlyk obtained his M.Sci diploma in 1972 (Mineralogy, Petrology)
from Lviv State University, Lviv, Ukraine, for petrological investigations of
volcanic rocks of Central Kamchatka, Russia, and Ph.D. diploma from
Moscow State University, Moscow, Russia in 1983 (Petrology, Volcanology)
for petrological investigations of kimberlite rocks of Yakutia, Russia.
Contact: phone 647-710-8514
E-mail [email protected]
About the Author
References 1. Dear Igor Kryvoshlyk,
My name is Bram Janse… As many other diamond exploration geologists I have been struggling to
understand the worldwide distribution of diamondiferous kimberlites and constructed maps with many photo lineaments, circles, zones, etc. but never achieved a satisfactory result…
…I was impressed by your spiderweb especially the construction of polygons to define favourable areas within a field… I like your garnet diagram. It does achieve a clear separation of eclogitic garnets which has always been a sore point…
With sincere regards, Bram Janse. (Bram is a distinguished geologist and chartered engineer internationally recognized for his expertise and long-term association with the diamond exploration industry. His experience spans more than 45 years of mineral exploration, specializing in diamond exploration on all continents .) Paramount Mining Corporation Ltd(618) 93285600 Ph(618) 93284430 FAX
Sun, March 15, 2009 3:41:43 AM
References
2. Dear Igor,
Many thanks for your prompt response. Your attached paper made fascinating reading – interesting research indeed.
Regards,
John Dr. John Ward, Group Mineral Resource ManagerNamakwa Diamonds Management Services (Pty) Ltd Member of the Diamond Dealers Club South Africa209 SA Diamond Centre, 225 Main StreetJohannesburg, 2001 (P. O. Box 2680 , Excom, 2023)Tel: +27 11 334-8886 Fax: +27 11 334-8885 Mobile: +27 79 491 7578
Sent: Thu, June 3, 2010 4:53:22 PMSubject: RE: Kimberlite Diamond Exploration
References
3. Hi Igor,
Just to say thank you very much more making the time to meet with me In New York yesterday.
Your ideas and model are very interesting
Regards
Graham WheelockGem Diamonds
Wed., September 2, 2009, 5:48:52 AM
Thank you