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Short course SC8 Exploration Geochemistry: Applying Fundamentals in the Field
Presenter
Dr. Peter Winterburn, Research Chair in Exploration Geochemistry Mineral Deposit Research Unit University of British Columbia, Vancouver, Canada [email protected] The Association of Applied Geochemists Keynote Lecturer
Date: Tuesday 2 April; One day; 8:30 am – 5:00 pm Short course description: An understanding of the basic geochemical concepts of element distribution and relationships from a global level to a mineral deposit scale will be combined with sampling theory and practices to provide a model-based geochemical exploration workshop. Sampling strategies, sample types, and key analytical methodologies will be discussed, leading into multi-element strategies for data interpretation and target selection and prioritisation. The workshop will utilise a variety of mineralisation styles including porphyry, IOCG, Sedimentary Cu, etc. to demonstrate how simple chemical principles can be applied to enhance discovery through the application of chemistry in mineral exploration. Course Contents:
1. Applying chemistry to geochemistry: Fundamentals of geochemistry; geochemistry of selected mineralisation styles; major and trace element behavior during weathering.
2. Design of geochemical surveys: Key considerations; deposit footprints; survey scale; climate and topography; residual, erosional, transported environments.
3. Analytical techniques and QA/QC: optimizing chemistry to maximise data value;
4. Data interpretation: Simple to complex; drawing the line; Data presentation – what the manager wants to see.
5. Exploration case studies: Porphyry Copper deposits in residual and concealed environments; Sedimentary hosted Cu deposits in complex terrains; Strategic Minerals.
6. Discovery through integrated geochemistry: possible futures. Innovations in
efficiency, methodology and value-add. Peter Winterburn Peter is an exploration geochemist with over 25 years of experience in industry prior to joining the Mineral Deposit Research Unit (MDRU) as a professor of exploration geochemistry at the University of British Columbia, Canada, in 2014. Peter was previously employed by Anglo American plc as their regional geochemist in Africa and subsequently in South America, based out of Santiago, Chile, following which he held the post of chief geochemist for global exploration with Vale, based out of Toronto, Canada. Peter has worked in over 60 countries representing a range of environments from tropical to arctic to arid deserts in both mountainous and subdued terrains. He is currently the NSERC/AcmeLabs/Bureau Veritas Minerals Research Chair in Exploration Geochemistry at MDRU, where he directs a program aimed at answering many of the questions and providing practical applications with respect to the discovery of mineral deposits through transported overburden. Peter has active research projects and students in British Columbia, the Northwest Territories, Colombia, and Chile, where he is working on a dominant theme of understanding the processes of anomaly generation and anomaly retention in the surface soils in areas where mineralisation is concealed by exotic materials. This research includes themes as diverse as regolith mapping, surface organic and inorganic geochemistry, soil mineralogy, structural mapping, extractive geochemistry, geochemistry in hyper-arid terrains and microbial genomics. Peter has run many successful workshops in the past including SEG Keystone 2018; RFG, Vancouver 2018; Roundup Vancouver-2019 in addition to private company workshops; all with a focus on applying concepts and theory in the field, laboratory and during interpretation. The workshop includes numerous examples of exploration geochemical practises. Included:
• Morning and afternoon tea, coffee and accompanying snacks • Presentations will be distributed for download via Dropbox before the workshop
Not included:
• Lunch (bring your own lunch or purchase during the 1 hour lunch break) Minimum number of participants: 15 Cost: To be notified. Cost includes morning and afternoon coffee/tea, but not lunch. Further information: Email Peter Winterburn at [email protected]
Gallery:
Exploration Geochemistry:Taking Fundamentals to the Field
Peter Winterburn Ph.D., P.Geo.Research Chair in Exploration Geochemistry
Loss or gain of electrons
• Changes the size of the atom• Ionic radius
• Gives the atom a charge• Ionic charge.
• The ionic charge : radius is a major controlling factor on what happens to trace elements in the real environment
Cu-Au-MoPorphyry Deposits
Los Bronces / AndinaPCD, Chile
Considerations.• Structure
• Controls original Intrusion• Controls fluid movement – alteration, lithocap, skarn
• Geology• Controls alteration reactions e.g. andesite vs rhyolite vs carbonates• Controls fluid movement - porosity
Figures from Urqueta 2006
Ni 95 ppm
Cu 63 ppm
Cr 670ppm
30
10
15
20
25
30
15
10
10
20
Kabanga (2007)9.7Mt @ 2.4% Ni ind. Res30.3Mt @ 2.8% Ni inf. Res
4KmBackground
Ni 25 ppm
Cu 25 ppmCr 66 ppm
-180micronSoil
AR-ICPMS
Regional Sampling
Squares are 1km2
Young folded mountain belt.
Target mineralisation – Porphyry Cu
4Km2
H
1
Li
3
Na
11
B
5
Al
13
C
6
Si
14
N
7
P
15
O
8
S
16
F
9
Cl
17
Ar
18
Ne
10
He
2
Be
4
57-71
89-103
Mg
12
Lr
103
No
102
Md
101
Fm
100
Es
99
Cf
98
Bk
97
Cm
96
Am
95
Pu
94
Np
93
K
19
Xe
54
Kr
36
Rb
37
Cs
55
Fr
87
V
23
Nb
41
Ta
73
Ca
20
Sr
38
Ba
56
Ra
88
Ti
22
Zr
40
Hf
72
Sc
21
Y
39
Rn
86
Br
35
I
53
At
85
Se
34
Te
52
Po
84
As
33
Sb
51
Bi
83
Ge
32
Sn
50
Pb
82
Ga
31
In
49
Tl
81
Zn
30
Cd
48
Hg
80
Cu
29
Ag
47
Au
79
Ni
28
Pd
46
Pt
78
Co
27
Rh
45
Ir
77
Fe
26
Ru
44
Os
76
Mn
25
Tc
43
Re
75
Cr
24
Mo
42
W
74
Pa
91
Th
90
Ac
89
U
92
Pr
59
Ce
58
La
57
Lu
71
Yb
70
Tm
69
Er
68
Ho
67
Dy
66
Tb
65
Gd
64
Eu
63
Sm
62
Pm
61
Nd
60
K
19
Xe
54
Kr
36
Rb
37
Cs
55
Fr
87
V
23
Nb
41
Ta
73
Ca
20
Sr
38
Ba
56
Ra
88
Ti
22
Zr
40
Hf
72
Sc
21
Y
39
Rn
86
Br
35
I
53
At
85
Se
34
Te
52
Po
84
As
33
Sb
51
Bi
83
Ge
32
Sn
50
Pb
82
Ga
31
In
49
Tl
81
Zn
30
Cd
48
Hg
80
Cu
29
Ag
47
Au
79
Ni
28
Pd
46
Pt
78
Co
27
Rh
45
Ir
77
Fe
26
Ru
44
Os
76
Mn
25
Tc
43
Re
75
Cr
24
Mo
42
W
74
Pa
91
Th
90
Ac
89
U
92
Pr
59
Ce
58
La
57
Lu
71
Yb
70
Tm
69
Er
68
Ho
67
Dy
66
Tb
65
Gd
64
Eu
63
Sm
62
Pm
61
Nd
60
Very Mobile
Mobile
Slightly Mobile
Immobile
Relative Mobility in Aqueous Solution under Oxidising Conditions with Acidic pH (pH <3)
Porphyry Weathering
ARD
AsMoCu
Surface
Bogs
Surface
BogsGround Ground
Surface
BogsGround
Cu
Rb Nb
Digestion – Stream Sediment
Total - XRF
”Total” - 4 Acid
Partial - Aqua-regia
DataLevelling
StreamSediments
Multi-element
Differentiation of targets
Principle Component AnalysisCLR DATARAW DATA
Alkali alumino-silicates
Ilmenite
ApatiteCalcite
Calcite
Apatite
Ilmenite
Alkali alumino-silicates
