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Hyperspectral Core Logging
AIG Drilling Workshop Mary Harris Project Geoscientist – Rio Tinto Exploration October 2015, Woodend
©2015, Rio Tinto, All Rights Reserved
Spectrometry
Electromagnetic spectrum Image taken from absoluteastronomy.com
©2015, Rio Tinto, All Rights Reserved
Spectrometry
Electromagnetic spectrum Image taken from absoluteastronomy.com
VNIR
Fe-oxides Mn-oxides Hydroxides
REEs
400nm – 1,000nm
SWIR
Hydroxyls Water
Carbonates Sulphates
Micas Amphiboles Tourmalines
1,000nm – 2,500nm
TIR
Carbonates Silicates Olivines
Pyroxenes Garnets
5,000nm – 14,000nm Spectral geology uses
the VNIR, SWIR and
TIR parts of the
electromagnetic
spectrum to identify
minerals
©2015, Rio Tinto, All Rights Reserved
Understanding spectra
Absorption features in the VNIR portion of the
spectrum represent mineral colours (e.g. the presence
of azurite will result in an absorption feature in the blue
portion of the spectrum), as well as sub-atomic and
electronic transitions (i.e. changes in iron from ferric
(Fe3+) to ferrous (Fe2+)). In the VNIR features are often
broad and their slope is important.
Ferric Ferrous VNIR
SWIR
Absorption features in the SWIR portion of the spectrum are
associated with sub-molecular vibrations generated by bending
and stretching of molecular bonds within minerals. The bonds
affected are hydroxyl (OH), water (H2O), carbonate (CO3) and
ammonia (NH4). In the SWIR, features are generally steep and
narrow.
Image courtesy of Scott Halley
©2015, Rio Tinto, All Rights Reserved
Hyperspectral core logging systems
©2015, Rio Tinto, All Rights Reserved
Corescan
• Process: Individual core boxes scanned row
by row. Height profiler aids in data processing
and QC
• Result: Mosaicked high resolution
hyperspectral imagery and photography
• Data Delivery: Web-based imagery
(Coreshed) & composited interval data (csv)
Image courtesy of Corescan
©2015, Rio Tinto, All Rights Reserved
Corescan
• Process: Individual core boxes scanned row
by row. Height profiler aids in data processing
and QC
• Result: Mosaicked high resolution
hyperspectral imagery and photography
• Data Delivery: Web-based imagery
(Coreshed) & composited interval data (csv)
Image courtesy of Corescan
©2015, Rio Tinto, All Rights Reserved
Corescan
• Process: Individual core boxes scanned row
by row. Height profiler aids in data processing
and QC
• Result: Mosaicked high resolution
hyperspectral imagery and photography
• Data Delivery: Web-based imagery
(Coreshed) & composited interval data (csv)
Image courtesy of Corescan
©2015, Rio Tinto, All Rights Reserved
Corescan
• Process: Individual core boxes scanned row
by row. Height profiler aids in data processing
and QC
• Result: Mosaicked high resolution
hyperspectral imagery and photography
• Data Delivery: Web-based imagery
(Coreshed) & composited interval data (csv)
Image courtesy of Corescan
©2015, Rio Tinto, All Rights Reserved
Corescan
• Process: Individual core boxes scanned row
by row. Height profiler aids in data processing
and QC
• Result: Mosaicked high resolution
hyperspectral imagery and photography
• Data Delivery: Web-based imagery
(Coreshed) & composited interval data (csv)
Image courtesy of Corescan
©2015, Rio Tinto, All Rights Reserved
Corescan
• Process: Individual core boxes scanned row
by row. Height profiler aids in data processing
and QC
• Result: Mosaicked high resolution
hyperspectral imagery and photography
• Data Delivery: Web-based imagery
(Coreshed) & composited interval data (csv)
Wavelength range
Spatial resolution
Spectral band width
Spectral resolution
Spectral bands
Scan time
VNIR – SWIR
50um (photography) 500um (spectra)
3.5nm
5nm
510
~5 min/metre
Image courtesy of Corescan
©2015, Rio Tinto, All Rights Reserved
TerraCore International (TCI)
• Process: Individual core boxes scanned as a
single image. Post-processing removes
background tray and slices into rows
• Result: Hyperspectral imagery and
photography
• Data Delivery: Web-based imagery (ALS
Coreview, TCI Intellicore)
©2015, Rio Tinto, All Rights Reserved
TerraCore International (TCI)
• Process: Individual core boxes scanned as a
single image. Post-processing removes
background tray and slices into rows
• Result: Hyperspectral imagery and
photography
• Data Delivery: Web-based imagery (ALS
Coreview, TCI Intellicore)
Image taken from TCI
©2015, Rio Tinto, All Rights Reserved
TerraCore International (TCI)
• Process: Individual core boxes scanned as a
single image. Post-processing removes
background tray and slices into rows
• Result: Hyperspectral imagery and
photography
• Data Delivery: Web-based imagery (ALS
Coreview, TCI Intellicore)
Wavelength range
Spatial resolution
Spectral band width
Spectral resolution
Spectral bands
Scan time
SWIR
100um
6.3nm
10nm
256
~1 min/tray ©2015, Rio Tinto, All Rights Reserved
Image taken from TCI
HyLogger (CSIRO)
• Process: Point scan along each row of a tray
and core photography
• Result: Core photography and spectral files
• Data Delivery: Interpretation of spectral files
using TSG accompanied by photography
©2015, Rio Tinto, All Rights Reserved
HyLogger (CSIRO)
• Process: Point scan along each row of a tray
and core photography
• Result: Core photography and spectral files
• Data Delivery: Interpretation of spectral files
using TSG accompanied by photography
Image courtesy of CSIRO ©2015, Rio Tinto, All Rights Reserved
HyLogger (CSIRO)
• Process: Point scan along each row of a tray
and core photography
• Result: Core photography and spectral files
• Data Delivery: Interpretation of spectral files
using TSG accompanied by photography
Wavelength range
Spatial resolution
Spectral band width
Spectral bands
Scan time
VNIR – SWIR – TIR
200um (photography) 8mm (spectra)
1.4nm – 9nm
Up to 1000
~1 min/tray
Image courtesy of CSIRO ©2015, Rio Tinto, All Rights Reserved
Mineral classification
• Identification of minerals to generate class maps
©2015, Rio Tinto, All Rights Reserved Image courtesy of Corescan
Composition and crystallinity
• Track changes in composition and crystallinity in host rock and structures
Image courtesy of Corescan ©2015, Rio Tinto, All Rights Reserved
Veins and structures
• Map vein mineralogy down-hole
Image courtesy of Corescan ©2015, Rio Tinto, All Rights Reserved
Support for geological logging
• Overlay these images
on core photography to
support core logging
Image courtesy of Corescan
©2015, Rio Tinto, All Rights Reserved
Domaining
• Stacked class map with mineral matches highlighting broad changes in alteration
©2015, Rio Tinto, All Rights Reserved Image courtesy of Corescan
Domaining
• Assist in alteration logging
©2015, Rio Tinto, All Rights Reserved Image courtesy of Corescan
Paragenesis
Late paragonitic white mica
(pale blue) cross-cutting
pervasive phengitic
muscovite
Later unaltered quartz vein
©2015, Rio Tinto, All Rights Reserved
Paragenesis
Late paragonitic white mica
(pale blue) cross-cutting
pervasive phengitic
muscovite
Later unaltered quartz vein
Strong phengitic alteration
of quartzite zoning into
higher temperature
paragonitic mica in clasts of
breccia
Montmorillonite alteration of
matrix in breccia
©2015, Rio Tinto, All Rights Reserved
Advantages of hyperspectral core scanning
Deliver data in real time to geologists
to support drill core logging
©2015, Rio Tinto, All Rights Reserved
Advantages of hyperspectral core scanning
Deliver data in real time to geologists
to support drill core logging
High quality core
photography
©2015, Rio Tinto, All Rights Reserved
Advantages of hyperspectral core scanning
Deliver data in real time to geologists
to support drill core logging
High quality core
photography
High spatial
resolution data
©2015, Rio Tinto, All Rights Reserved
Advantages of hyperspectral core scanning
Deliver data in real time to geologists
to support drill core logging
High quality core
photography
High spatial
resolution data
Systematic and
unbiased data collection
©2015, Rio Tinto, All Rights Reserved
Advantages of hyperspectral core scanning
Integration with other datasets
to build more robust 3D models
Deliver data in real time to geologists
to support drill core logging
High quality core
photography
High spatial
resolution data
Systematic and
unbiased data collection
©2015, Rio Tinto, All Rights Reserved
Advantages of hyperspectral core scanning
Integration with other datasets
to build more robust 3D models
Deliver data in real time to geologists
to support drill core logging
High quality core
photography
High spatial
resolution data
Systematic and
unbiased data collection
Adding value down the chain
©2015, Rio Tinto, All Rights Reserved
Questions…
©2015, Rio Tinto, All Rights Reserved