Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit,...

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HBM Presented at TGDG, Toronto, ON | January 31, 2017 Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona by Juan Carlos Ordóñez-Calderón Sergio Gelcich

Transcript of Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit,...

Page 1: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

HBM

Presented at TGDG, Toronto, ON | January 31, 2017

Geology, Chemostratigraphy, and Alteration

Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit,

Southern Arizona by

Juan Carlos Ordóñez-Calderón

Sergio Gelcich

Page 2: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Contents

PRESENTATION | 2

Rosemont Geology and Mineralization

Part 1. Unsupervised Data Analysis: Compositional Data Analysis

for Lithogeochemistry and Chemostratigraphy

Part 2. Supervised Data Analysis: Predictive Models of Skarn

Alteration Facies

Conclusions

Acknowledgments

References

Page 3: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Rosemont Geology and Mineralization

PRESENTATION | 3

Regional geological context

Backbone Footwall Block

Graben Block Lower Plate

Upper Plate

Page 4: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Rosemont Geology and Mineralization

PRESENTATION | 4

Structural domains

Page 5: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Rosemont Geology and Mineralization

PRESENTATION | 5

Stratigraphy

Meso-cenozoic sequence

Paleozoic sequence

Precambrian Basement

Page 6: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Part 1. Unsupervised Data Analysis

PRESENTATION | 6

Compositional Data Analysis for

Lithogeochemistry and Chemostratigraphy Motivation for Compositional Data Analysis

What is compositional data (CoDa)

Motivation 1: Spurious correlations

Motivation 2: Problem with distances; a synthetic example

Exploratory Data Analysis

Cluster analysis on compositional variables

Principal component analysis

Mapping the Geochemical Space

Different sample spaces

Mapping in the simplex

Lithogeochemical model

Relationships between grades and lithogeochemistry

Mapping the Geospace

Geospatial distribution of lithogeochemical classes

Simplified chemostratigraphy

Page 7: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Motivation for Compositional Data Analysis

What is compositional data (CoDa)

PRESENTATION | 7

Compositional Data (CoDa) are vectors of positive components that

sum to a constant (e.g., 1, 100, 1 million, 1 billion, etc).

Those vectors represent parts of a whole which only carry relative

information.

Examples of compositional data include geochemical and

mineralogical data.

Standard multivariate statistical methods are not directly applicable

to compositional data in their raw form.

John Aitchison (1986)

Page 8: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Motivation for Compositional Data Analysis

Motivation 1: Spurious correlations

PRESENTATION | 8

Al

0 2000 6000 10000

020000

60000

02000

6000

10000

Ti

0 20000 60000 0 50000 150000

050000

150000

Fe

Al

0.00 0.02 0.04 0.06 0.08

0.0

0.2

0.4

0.6

0.8

0.0

00.0

20.0

40.0

60.0

8

Ti

0.0 0.2 0.4 0.6 0.8 0.2 0.4 0.6 0.8 1.0

0.2

0.4

0.6

0.8

1.0

Fe

Closed 3-part subcomposition scatter plot matrix Full composition scatter plot matrix

Karl Pearson (1897); Felix Chayes (1960); John Aitchison (1986)

Page 9: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Motivation for Compositional Data Analysis

Motivation 2: Problems with distances; a synthetic example

PRESENTATION | 9

-2 -1 0 1 2

-2-1

01

2

Compositional Data : Centred log ratios

clrAl2O3

Clr

SiO

20 20 40 60 80 100

02

04

06

08

01

00

Compositional Data : Raw Scale

x= Al2O3 (%)

y=

SiO

2 (

%)

1

2 3 3

2

1

Al2O3 SiO2 samp1 19.49 80.51 samp2 5.54 94.46 samp3 1.40 98.60

Al2O3 SiO2

samp1 + mass addition 19.49 (80.51+251.96) = samp2 + mass addition 19.49 ((80.51+251.96)+1040.48) =

Closure Al2O3 SiO2

Altered samp2 5.54 94.46 Altered samp3 1.40 98.60

Raw Geochemical Data Centered Log Ratio Transformation

𝑐𝑙𝑟 𝑥 = ln𝑥𝑖

𝑔𝑚(𝑥) 𝑖 = 1, … . , D

Page 10: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Exploratory Data Analysis

Variation Matrix

PRESENTATION | 10

Al Ca Ce Co Cr Hf La Mg Nb Ni P Sc Ta Th Ti V Y Zr

Al 0 5.78 0.23 0.93 1.54 0.71 0.43 2.92 0.13 1.58 1.24 0.38 0.35 0.26 0.22 0.84 0.73 0.82

Ca 5.78 0 4.82 4.16 2.26 3.73 4.02 2.01 5.09 2.40 3.65 4.34 4.37 5.75 5.54 3.68 3.17 3.80

Ce 0.23 4.82 0 0.70 1.15 0.61 0.10 2.43 0.18 1.22 1.00 0.31 0.30 0.29 0.32 0.61 0.41 0.73

Co 0.93 4.16 0.70 0 1.01 0.77 0.74 1.95 0.69 1.02 1.16 0.68 0.84 1.22 0.79 0.44 0.81 0.83

Cr 1.54 2.26 1.15 1.01 0 0.99 0.85 1.26 1.21 0.26 0.87 0.88 1.00 1.73 1.35 0.68 0.62 1.06

Hf 0.71 3.73 0.61 0.77 0.99 0 0.61 1.82 0.50 1.06 1.16 0.65 0.59 0.87 0.69 0.78 0.66 0.12

La 0.43 4.02 0.10 0.74 0.85 0.61 0 2.16 0.34 0.96 0.75 0.29 0.29 0.48 0.53 0.51 0.21 0.77

Mg 2.92 2.01 2.43 1.95 1.26 1.82 2.16 0 2.50 1.23 2.25 2.32 2.30 2.92 2.70 2.02 1.90 1.74

Nb 0.13 5.09 0.18 0.69 1.21 0.50 0.34 2.50 0 1.26 1.11 0.30 0.23 0.31 0.17 0.65 0.53 0.62

Ni 1.58 2.40 1.22 1.02 0.26 1.06 0.96 1.23 1.26 0 1.00 0.93 1.13 1.82 1.31 0.84 0.73 1.10

P 1.24 3.65 1.00 1.16 0.87 1.16 0.75 2.25 1.11 1.00 0 0.84 0.93 1.52 1.23 0.72 0.70 1.31

Sc 0.38 4.34 0.31 0.68 0.88 0.65 0.29 2.32 0.30 0.93 0.84 0 0.17 0.64 0.34 0.46 0.34 0.90

Ta 0.35 4.37 0.30 0.84 1.00 0.59 0.29 2.30 0.23 1.13 0.93 0.17 0 0.51 0.46 0.64 0.36 0.86

Th 0.26 5.75 0.29 1.22 1.73 0.87 0.48 2.92 0.31 1.82 1.52 0.64 0.51 0 0.47 1.13 0.77 0.99

Ti 0.22 5.54 0.32 0.79 1.35 0.69 0.53 2.70 0.17 1.31 1.23 0.34 0.46 0.47 0 0.74 0.74 0.77

V 0.84 3.68 0.61 0.44 0.68 0.78 0.51 2.02 0.65 0.84 0.72 0.46 0.64 1.13 0.74 0 0.53 0.87

Y 0.73 3.17 0.41 0.81 0.62 0.66 0.21 1.90 0.53 0.73 0.70 0.34 0.36 0.77 0.74 0.53 0 0.87

Zr 0.82 3.80 0.73 0.83 1.06 0.12 0.77 1.74 0.62 1.10 1.31 0.90 0.86 0.99 0.77 0.87 0.87 0

Variation Matrix

𝑡𝑖𝑗 = var lnxi

xj The variance of the logratio of parts i and j

Page 11: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Exploratory Data Analysis

Cluster analysis on compositional variables

PRESENTATION | 11

N scatter plots= D(D − 1)/2 N scatter plots = 820

Page 12: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Exploratory Data Analysis

Cluster analysis on compositional variables

PRESENTATION | 12

N scatter plots= D(D − 1)/2 N scatter plots = 153

Page 13: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Exploratory Data Analysis

Principal Component Analysis

PRESENTATION | 13

PC biplot on 18 variables

Cluster dendrogram on 18 variables

Page 14: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Mapping the Geochemical Space

Different sample spaces

PRESENTATION | 14

3D-Simplex

ilr-balances; 3D Real space

Raw data; 3D space

𝑏𝑖 = 𝑟 ∗ 𝑠

𝑟 + 𝑠 ln

𝑔𝑚(𝑐+)

𝑔𝑚(𝑐−)

𝑔𝑚 = 𝑥𝑖

𝑛

𝑖=1

1/𝑛

= 𝑥1𝑥2 …𝑥𝑛𝑛

Page 15: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Mapping the Geochemical Space

Mapping in the Simplex

PRESENTATION | 15

Cluster dendrogram on 18 variables

Effective geochemical mapping relies on good

understanding of the geometry of the

geochemical space; as much as geological

mapping relies in understanding the structural

geometry of the geospace.

Page 16: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Mapping the Geochemical Space

PRESENTATION | 16

Centered data Non centered data

Mapping in the Simplex

Centering operation

𝑐𝑒𝑛𝑡𝑒𝑟𝑒𝑑(𝑋) = 𝐶 1

𝑔𝑚(𝑥1),

1

𝑔𝑚(𝑥2),

1

𝑔𝑚(𝑥3)

Page 17: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Mapping the Geochemical Space

Lithogeochemical model

PRESENTATION | 17

SC = ZrHfThTiAlNbScTaYLaCeCrNiPCoV Lm= Ca Dol= Mg

Lithogeochemical Classes

Siliciclastic-Crystalline

Siliciclastic-Limestone

Siliciclastic-Dolostone

Limestone-Siliciclastic

Dolostone-Siliciclastic

Limestone

Dolostone

Page 18: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Mapping the Geochemical Space

PRESENTATION | 18

Copper (ppm) Box Plot 2D Simplex

Relationships between grades and the lithogeochemistry

Page 19: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Mapping the Geospace

PRESENTATION | 19

Geospatial distribution of lithogeochemical classes

Page 20: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Predictive Model in the Geospace

PRESENTATION | 20

Simplified chemostratigraphy

Upper plate arkose

Page 21: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Part 2. Supervised Data Analysis

PRESENTATION | 21

Predictive Models of Skarn Alteration Facies

Exploratory Data Analysis on Quantitative Mineralogy

Cluster analysis on variables vs. principal component analysis

Basic Concepts of Predictive Modelling

Model bias versus model variance; a synthetic example

Choosing the Best Predictive Model for Skarn Classification

Cross-validation: Training and test set accuracy

Rationale behind tree-based methods

The confusion matrix; assessing the predictive models by class

Quality of geological core logging by class

Predictive Models in the Geospace

Mapping the random forest predictive skarn model

Spatial relationships between skarn facies and porphyries

Page 22: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Exploratory Data Analysis

PRESENTATION | 22

Cluster Dendrogram

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nit

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020

40

60

80

100

12

0

Qu

art

z

Calcic skarn

gnpxwovs

Magnesian skarn

SpAm

Epidote skarn

Ep

Cluster analysis on variables vs. principal component analysis

-20 -10 0 10 20

-20

-10

010

20

Form Biplot

Principal Component 1

-0.5 0.0 0.5

-0.5

0.0

0.5

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WollastoniteVesuvianite

Garnet

Calcite

DolomitePyroxene

SerpentineAmphibole

K-feldspar

Plagioclase

Quartz

Epidote

Pri

ncip

al C

om

po

nen

t 2

400 samples with mineralogy

>30,000 samples with geochemistry

Page 23: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Basic Concepts of Predictive Modelling

Model bias versus model variance; a synthetic example

PRESENTATION | 23

0.0 0.2 0.4 0.6 0.8 1.0

-6-5

-4-3

-2-1

0

Training Data

Predictor Variable x

Response V

ari

able

y

0.0 0.2 0.4 0.6 0.8 1.0

-6-5

-4-3

-2-1

0

Test Data

Predictor Variable x

Response V

ari

able

y

RSE1= 0.15 RSE2= 0.26 (↑73%)

Page 24: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Basic Concepts of Predictive Modelling

PRESENTATION | 24

0.0 0.2 0.4 0.6 0.8 1.0

-6-5

-4-3

-2-1

0

Training Data

Predictor Variable x

Response V

ari

able

y

0.0 0.2 0.4 0.6 0.8 1.0

-6-5

-4-3

-2-1

0

Test Data

Predictor Variable x

Response V

ari

able

y0.0 0.2 0.4 0.6 0.8 1.0

-6-5

-4-3

-2-1

0

Training Data

Predictor Variable x

Response V

ari

able

y0.0 0.2 0.4 0.6 0.8 1.0

-6-5

-4-3

-2-1

0

Test Data

Predictor Variable x

Response V

ari

able

y

RSE1= 0.15 RSE2= 0.26 (↑73%)

RSE1= 0.46 (↑207%) RSE2= 0.31 (↑20%) I.E = 0.27

Key concepts • Bias • Variance • Overfitting • Irreducible Error (I.E)

Optimum balance between bias and variance

Model bias versus model variance; a synthetic example

Page 25: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Choosing the Best Predictive Model

Cross-validation: Training and test set accuracy

PRESENTATION | 25

Support vector machines (SVM)

Quadratic discriminant analysis (QDA)

Linear discriminant analysis (LDA)

Classification and regression trees

(CART)

Random forests (RF)

Training set

90%

Test set

10%

10-fold cross-validation

Page 26: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Choosing the Best Predictive Model

PRESENTATION | 26

Cross-validation: Training and test set accuracy

Support vector machines (SVM)

Quadratic discriminant analysis (QDA)

Linear discriminant analysis (LDA)

Classification and regression trees

(CART)

Random forests (RF)

Page 27: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Choosing the Best Predictive Model

PRESENTATION | 27

Rationale behind tree-based methods

Page 28: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Choosing the Best Predictive Model

The confusion matrix; assessing the predictive models by class

PRESENTATION | 28

Garnet-Pyroxene-Wollastonite-Vesuvianite Serpentine-Amphibole Epidote Least Altered

Garnet-Pyroxene-Wollastonite-Vesuvianite 79% 7% 5% 9% 100%

Serpentine-Amphibole 10% 70% 5% 15% 100%

Epidote 15% 2% 72% 11% 100%

Least Altered 7% 5% 4% 84% 100%

Garnet-Pyroxene-Wollastonite-Vesuvianite Serpentine-Amphibole Epidote Least Altered

Garnet-Pyroxene-Wollastonite-Vesuvianite 86% 17% 26% 9%

Serpentine-Amphibole 5% 72% 9% 7%

Epidote 2% 1% 47% 2%

Least Altered 7% 10% 18% 82%

100% 100% 100% 100%

True Classes

Pre

dic

ted

Cla

ss

es

True Classes

Pre

dic

ted

Cla

ss

es

Random Forest (nt= 500, m=15) Confusion Matrix Test Set Precision

Garnet-Pyroxene-Wollastonite-Vesuvianite Serpentine-Amphibole Epidote Least Altered

Garnet-Pyroxene-Wollastonite-Vesuvianite 79% 7% 5% 9% 100%

Serpentine-Amphibole 10% 70% 5% 15% 100%

Epidote 15% 2% 72% 11% 100%

Least Altered 7% 5% 4% 84% 100%

Garnet-Pyroxene-Wollastonite-Vesuvianite Serpentine-Amphibole Epidote Least Altered

Garnet-Pyroxene-Wollastonite-Vesuvianite 86% 17% 26% 9%

Serpentine-Amphibole 5% 72% 9% 7%

Epidote 2% 1% 47% 2%

Least Altered 7% 10% 18% 82%

100% 100% 100% 100%

True Classes

Pre

dic

ted

Cla

ss

es

True Classes

Pre

dic

ted

Cla

ss

es

Random Forest (nt= 500, m=15) Confusion Matrix Test Set True Class Prediction Rate

Page 29: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Choosing the Best Predictive Model

Quality of geological core logging by class

PRESENTATION | 29

Garnet-Pyroxene-Wollastonite-Vesuvianite Serpentine-Amphibole Epidote Least Altered

Garnet-Pyroxene-Wollastonite-Vesuvianite 66% 13% 7% 14% 100%

Serpentine-Amphibole 13% 57% 3% 26% 100%

Epidote 13% 0% 37% 50% 100%

Least Altered 20% 12% 5% 63% 100%

Unknown 32% 15% 12% 41% 100%

Garnet-Pyroxene-Wollastonite-Vesuvianite Serpentine-Amphibole Epidote Least Altered

Garnet-Pyroxene-Wollastonite-Vesuvianite 58% 25% 27% 12%

Serpentine-Amphibole 4% 34% 4% 7%

Epidote 2% 0% 19% 6%

Least Altered 16% 21% 16% 50%

Unknown 20% 20% 33% 25%

100% 100% 100% 100%

True Classes

Pre

dic

ted

Cla

ss

es

True Classes

Pre

dic

ted

Cla

ss

es

Geologist Visual Core Logging Confusion Matrix True Class Prediction Rate

Geologist Visual Core Logging Confusion Matrix True Class Prediction Rate

Garnet-Pyroxene-Wollastonite-Vesuvianite Serpentine-Amphibole Epidote Least Altered

Garnet-Pyroxene-Wollastonite-Vesuvianite 66% 13% 7% 14% 100%

Serpentine-Amphibole 13% 57% 3% 26% 100%

Epidote 13% 0% 37% 50% 100%

Least Altered 20% 12% 5% 63% 100%

Unknown 32% 15% 12% 41% 100%

Garnet-Pyroxene-Wollastonite-Vesuvianite Serpentine-Amphibole Epidote Least Altered

Garnet-Pyroxene-Wollastonite-Vesuvianite 58% 25% 27% 12%

Serpentine-Amphibole 4% 34% 4% 7%

Epidote 2% 0% 19% 6%

Least Altered 16% 21% 16% 50%

Unknown 20% 20% 33% 25%

100% 100% 100% 100%

True Classes

Pre

dic

ted

Cla

ss

es

True Classes

Pre

dic

ted

Cla

ss

es

Page 30: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Predictive Model in the Geospace

Mapping the random forest predictive skarn model

PRESENTATION | 30

Skarn Class Garnet-Pyroxene-Wollastonite-Vesuvianite

Serpentine-Amphibole

Epidote

Least Altered

Page 31: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Predictive Model in the Geospace

PRESENTATION | 31

Garnet-Pyroxene-Wollastonite-Vesuvianite

Skarn Class

Serpentine-Amphibole

Epidote

Porphyries

Low angle fault

Backbone fault

Spatial relationships between skarn facies and porphyries

Page 32: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Acknowledgments

PRESENTATION | 32

Page 33: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

References

PRESENTATION | 33

Aitchison, J., 1986. The Statistical Analysis of Compositional Data. Monographs on Statistics and Applied Probability. London, Chapman &

Hall, 416 pp.

Buccianti, A., Mateu-Figueras, G., Pawlowsky-Glahn, V., (eds) 2006. Compositional Data Analysis in the Geosciences: From Theory to

Practice. Geological Society, London, Special Publications, 264 pp.

Chayes, F., 1960. On Correlation Between Variables of Constant Sum. Journal of Geophysical Research, 65 (12), 4185-4193.

Chayes, F., 1971. Ratio Correlation, University of Chicago Press, Chicago, IL, 99 pp.

Egozcue, J.J., Pawlowsky-Glahn, V., 2005. Groups of Parts and Their Balances in Compositional Data Analysis. Mathematical Geology,

37(7), 795-828.

Egozcue, J.J., Pawlowsky-Glahn, V., Mateu-Figueras, G., Barceló-Vidal, C., 2003. Isometric Logratio Transformations for Compositional

Data Analysis. Mathematical Geology, 35 (3), 279-300.

Hastie, T., Tibshirani, R., Friedman, J., 2009. The Elements of Statistical Learning: Data Mining, Inference, and Prediction, 2nd Ed.

Springer, 745 pp.

James, G., Witten, D., Hastie, T., Tibshirani, R., 2015. An Introduction to Statistical Learning: with Applications in R. Springer, 426 pp.

Kuhn, M., Johnson, K., 2013. Applied Predictive Modeling. Springer, 600 pp.

Martín-Fernández, J.A., Barceló-Vidal, C., Pawlowsky-Glahn, V., 1998. A Critical Approach to Non-parametric Classification of

Compositional Data. In: Rizzi, A., Vichi, M., Bock, H., (eds). Advances in Data Science and Classification. Proceedings of the 6th

Conference of the International Federation of Classification Societies (IFCS-98), Rome, July 21-24, 1998. Springer, 49-56.

Pawlowsky-Glahn, V., Buccianti, A., (eds) 2011. Compositional Data Analysis: Theory and Applications. John Wiley & Sons, Ltd., 378 pp.

Pawlowsky-Glahn, V., Egozcue, J.J., Tolosana-Delgado, R., (eds) 2015. Modeling and Analysis of Compositional Data. John Wiley &

Sons, Ltd., 247 pp.

Pearson, K., 1897. Mathematical Contributions to the Theory of Evolution. On a form of Spurious correlation Which May Arise When

Indices Are Used in the Measurement of Organs. Proceedings of the Royal Society of London, LX, 489-502.

R Core Team 2017. R: A Language and Environment for Statistical Computing. R Foundation for Statistical. Computing, Vienna, Austria,

https://www.r-project.org/

van den Boogaart, K.G., Tolosana-Delgado, R., (eds) 2013. Analyzing Compositional Data with R. Springer, 258 pp.

Tolosana-Delgado, R., Otero, N., Pawlowsky-Glahn, V., 2005. Some Basic Concepts of Compositional Geometry. Mathematical Geology,

37 (7), 673-680.

Page 34: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

Software

PRESENTATION | 34

R packages for statistical computing

Adler, D., Murdoch, D., 2017. R Package “rgl”, Version 0.97.0. 3D Visualization Using OpenGL, 143 pp.

Breiman, L., Cutler, A., Liaw, A., Wiener, M., 2015. R Package “randomForest”, Version 4.6-12. Breiman and Cutler's Random Forests for

Classification and Regression, 29 pp.

Meyer, D., Dimitriadou, E., Hornik, K., Weingessel, A., Leisch, F., Chang, C-C., Lin, C-C., 2015. R Package “e1071”, Version 1.6-7. Misc

Functions of the Department of Statistics, Probability Theory Group (Formerly: E1071), TU Wien, 62 pp.

R Core Team 2017. R: A Language and Environment for Statistical Computing. R Foundation for Statistical. Computing, Vienna, Austria,

https://www.r-project.org/

Ripley, B., 2016. R Package “tree”, Version 1.0-37. Classification and Regression Trees, 19 pp.

Ripley, B., Venables, B., Bates, D.M., Hornik, K., Gebhardt, A., Firth, D., 2016. R Package “MASS”, Version 7.3-45. Support Functions and

Datasets for Venables and Ripley's MASS, 169 pp.

van den Boogaart, K.G., Tolosana-Delgado, R., Bren, M., 2015. R Package “compositions”, Version 1.40-1. Compositional Data Analysis,

264 pp.

3D modeling software

Leapfrog Geo, Version 4.0.

Data visualization

Adler, D., Murdoch, D., 2017. R Package “rgl”, Version 0.97.0. 3D Visualization Using OpenGL, 143 pp.

ioGAS, Reflex, Version 6.2.1

Page 35: Geology, Chemostratigraphy, and Alteration Geochemistry of the Rosemont Cu-Mo-Ag Skarn Deposit, Southern Arizona

For more information contact:

Juan Carlos Ordóñez-Calderón, Geochemist

416.564.4174 | [email protected]

For investor inquiries, please contact:

Candace Brûlé, Director, Investor Relations

416.814.4387 | [email protected]