This is the presentation for a webinar that we recently held, explaining the use of energy-dispersive spectrometry (EDS) on the scanning electron microscope (SEM) and micro-X-ray fluorexcence spectrometry (µ-XRF) in geosciences. You will find lots of interesting applications from this field. If you are interested in viewing a recording of the webinar, please follow this link: https://bruker.webex.com/bruker/lsr.php?AT=pb&SP=EC&rID=65244917&rKey=c8fbbf90d4bab945

1. X-ray Expeditions into Geosciences
and Mining
Geosciences Applications of EDS and µ-XRF
Bruker Nano GmbH, Berlin
Webinar, April25th, 2012
Innovation with Integrity

2. Webinar Overview
Part I
Advanced EDS analysis options for geoscience applications
using SDD on SEM
Part II
Geological applications of the M4 TORNADO µ-XRF spectrometer

3. Advanced EDS Analysis Options for
Geoscience Applications using SDD
Dr. Tobias Salge, EDS Application Scientist,
Bruker Nano GmbH, Berlin

4. QUANTAX EDS system for
SEM, EPMA and TEM
State-of-the-art XFlash® silicon drift detectors (SDD)
• Energy resolution 121 eV (FWHM Mn Kα)
• Best energy resolution range up to 100 kcps
• Multi detector option
03.05.2012 4

5. Overview
• Fast, high resolution mapping
 Display of small features
• Spectrum imaging
 Improved element identification
 Quantitative analysis of REE by peak deconvolution
 Modal analysis
• Computer-controlled SEM
 High resolution at the macroscale
 Particle search using feature analysis
• Application examples
 Earth and planetary samples
 Core samples of impactites at the K-Pg boundary
 Mining samples focussing on REE, iron oxides
03.05.2012 5

6. K-Pg boundary
Asteroid impact and mass extinction
Chicxulub impact structure
• ~Ø 180 km, ~65 Ma
• Target rock:
silicate basement,
3 km sediments
• Release of
SOx, CO2, H2O
Chicxulub
crater
Yax-1
UNAM-7
Image of NASA Worldwind
OPD leg 207 (4000 km from crater)
03.05.2012 6

7. K-Pg transition at OPD leg 207
2 cm ejecta spherule deposit
Schulte et al. 2009
Thin section
03.05.2012 7

8. ODP leg 207, High-resolution map
4072x3072 pixel, 30 min, 500 kcps
Schulte et al. 2010,
Science, 327, 1214-1218
Dolomite spherule
with layered clay shell
indicates impact-induced
mechanical and thermal
stress.
03.05.2012 8

9. Spectrum Imaging
HyperMap
03.05.2012 9

10. Spectrum Imaging
HyperMap
03.05.2012 10

11. Spectrum Imaging
HyperMap
03.05.2012 11

12. Element Identification
Maximum Pixel Spectrum vs. Sum Spectrum
• Synthetic spectrum of highest
count level found in each
spectrum channel
• Detection of trace elements
present in one pixel
MaxPixSpec reveals the presence of
200 µm Th, La, Ce, …
Granite
03.05.2012 12

13. Element Identification
Maximum Pixel Spectrum vs. Sum Spectrum
• Synthetic spectrum of highest
count level found in each
spectrum channel
• Detection of elements present
in a few pixels only
wt.%
Monazite
(La, Ce, Nd, Pr…)PO4
MaxPixSpec reveals the presence of
Ce 200 µm Th, La, Ce, …
Granite
03.05.2012 13

14. How far can we take peak deconvolution?
Diagenetic monazite concretion
03.05.2012 14

15. How far can we take peak deconvolution?
Diagenetic monazite concretion
Peak intensity map Area spectra
La Gd
300 µm
Intensity map and area spectra display zonation.
03.05.2012 15

16. How far can we take peak deconvolution?
Diagenetic monazite concretion
Peak intensity map Area spectra
Gd
300 µm
Overlapping element lines lead to wrong display
of element distribution.
03.05.2012 16

17. How far can we take peak deconvolution?
Diagenetic monazite concretion
Quantitative map wt.% Deconvolution result
>5.1
4.7
3.5
2.4
1.2
Gd
300 µm 0.0
• Overlapping peaks can be deconvolved
• Quantitative map displays correct element distribution
03.05.2012 17

18. How far can we take peak deconvolution?
Diagenetic monazite concretion
Line scan (wt.%) extracted from quantitative map:
• Concentration of Gd, Sm, Nd within the core
• Sequential incorporation of LREE
• La dominating the outermost rim
03.05.2012 18

19. Modal analysis
Chemical phase mapping UNAM-7
Core: UNAM-7 381.4 m Microcrystalline breccia matrix
Matrix
Anh
Matrix
Matrix
1 cm
BSE 80 µm
Salge et al. 2007
03.05.2012 19

20. Modal analysis
Chemical phase mapping UNAM-7
Core: UNAM-7 381.4 m Autophase result
Matrix
Anh
Matrix
Matrix
1 cm
80 µm
Salge et al. 2008
03.05.2012 20

21. Modal analysis
Chemical phase mapping UNAM-7
Core: UNAM-7 381.4 m Modal content
Matrix Phase Area fraction (%)
Anhydrite 51.8
Anh Dolomite 30.6
Calcite 14.9
K-feldspar 1.0
Matrix Celestine 0.7
Na-feldspar 0.5
Matrix
1 cm
80 µm
Salge et al. 2008
03.05.2012 21

22. Computer-controlled SEM
Jobs – StageControl
03.05.2012 22

23. High resolution at the macroscale Yax-1
140 megapixel map
Yax-1 core: Unit 5 861.72m
Melt rock
1 cm Matrix
Composite of 276 maps
• 2 µm pixel resolution
• 11,906 x 11,595 pixel
• ICR: 450,000 cps
• 20 kV, 18 nA, 18 h
(4 min per single map)
5 mm
Nelson et al. (in press, available online at GCA)
03.05.2012 23

24. High resolution at the macroscale Yax-1
140 megapixel map
Yax-1 core: Unit 5 861.72m
Next image
Melt rock
1 cm Matrix
Composite of 276 maps
• 2 µm pixel resolution
• 11,906 x 11,595 pixel
• ICR: 450,000 cps
• 20 kV, 18 nA, 18 h
(4 min per single map)
5 mm
Nelson et al. (in print, available online at GCA)
03.05.2012 24

25. K-metasomatism Yax-1
Multiple fracturing events
1 mm
Impact melt
Matrix
Matrix
Impact melt
• Crystallized impact melt material with
hydrothermal overprint.
• Multiple fracturing events due to interaction
of hot fluids with solidified melts.
03.05.2012 25

26. Particle detection and classification
Feature analysis
1. Particle detection
2. Chemistry:
Chemical classification
3. Review:
Reclassification
03.05.2012 26

27. Particle detection and classification
Feature analysis
Morphological classification dialog: Binarization
03.05.2012 27

28. Particle detection and classification
Feature analysis
2. Chemical classification
03.05.2012 28

29. Discrimination of calcite and flourite
Feature analysis
Composite of 14 BSE images
20 kV, 60 kcps, 0.5 s
Class Count Area fraction (%)
Fluorite CaF2 130 9.2
Ca-carbonate CaCO3 4 2.3
Unclassified 482 68.5
All 616 100
03.05.2012 29

30. Altered laterite
Classification of monazite and pyrochlore
Composite of 64 BSE images
Bariopyrochlore Ba0.3Sr0.2Ca0.1Nb1.8Ti0.2O5.6(H2O)0.8
Plumbopyrochlore Pb0.8Y0.2U0.1Ca0.1Nb1.4Si0.2Fe2+0.2Ta0.1O6.2(OH)0.5
Zirconolite Ca0.8Ce0.2ZrTi1.5Fe2+0.3Nb0.1Al0.1O7
Hollandite Ba0.8Pb0.2Na0.1Mn4+6.1Fe3+1.3Mn2+0.5Al0.2Si0.1O16
03.05.2012 30

31. Pyrochlore
Deconvolution of overlapping peaks
Pyrochlore spectrum XFlash® 5030, 20 kV, 90-120 kcps, 3 s
cps/eV cps/eV cps/eV
24
120 4.0
22
20 3.5
100
18
3.0
16
80
14 2.5
12 Ba
60 2.0
Ta Sr Zr Nb Pb Ti Ce Fe Th U Ca
10
8 1.5
40
6 1.0
20 4
0.5
2
0 0 0.0
1.80 2.00 2.20 2.40 2.60 4.2 4.4 4.6 4.8 5.0 5.2 5.4 5.6 5.8 6.0 6.2 6.4 6.6 2.90 3.00 3.10 3.20 3.30 3.40 3.50 3.60 3.703.80
keV keV keV
03.05.2012 31

32. Classification
Standardless quantification
Class Count
Monazite Nd>8 wt.% 123
Monazite La>18 wt.% 551
Monazite 669
Baryte 32
Hollandite 22
Plumbopyrochlore 15
Bariopyrochlore 20
Zirconolite 2
Unclassified 43
All 1477
03.05.2012 32

33. Classification of monazite
Composition
Ce versus Nd La versus Nd
12.4
La versus Nd
12.4
La versus Nd
Nd Ce versus Nd Nd
12,4 12,4
11.1 11,1 11.1 11,1
9.9 9,9 9.9 9,9
8.7 8,7
8.7 8,7
Nd (wt.%)
Nd (wt.%)
7.4 7,4
7.4 7,4
6.2 6,2
6.2 6,2
4.9 4,9 4.9 4,9
3.7 3,7
3.7 3,7
2.5 2,5 2.5 2,5
1.2 1,2
1.2 1,2
0.0 0,0
0.0 0,0
0.0 2.3 4.5 6.8 9.0 11.3 13.5 15.8 18.0 20.3 22.5
0,0 2,3 4,5 6,8 9,0 11,3 13,5 15,8 18,0 20,3 22,5
5.9 14.8 17.8 20.7 13.7 26.6 29.6
0,0 3,0 5,9 8,9 11,8 14,8 17,8 20,7 23,7 26,6 29,6
0.0 3.0 8.9 11. Ce La
8
Ce (wt.%) La (wt.%)
• An exchange of neodynium with lanthanum is present.
03.05.2012 33

34. Monazite La-Monazite Nd-Monazite

35. Iron oxides
Fast quantification using a standard
Haematite Fe2O3 and Magnetite Fe3O4 Haematite Fe2O3
• Standard-based quantification is Expected Mean s
N=10
required to obtain highest accuracy. (at.-%) (at.-%) (±at.-%)
O 60.0 60.0 0.5
• Haematite was used for reference. Fe 40.0 40.0 0.5
• Using high count rates, iron oxides can Magnetite Fe3O4
be discriminated in a short time.
N=10 Expected Mean s
(at.-%) (at.-%) (±at.-%)
O 57.1 56.9 1.0
Fe 42.9 43.1 1.0
Count rate (In/Out): 900/675 kcps EDX detector: XFlash® 5040 QUAD
Time reference/sample: 120/30 ms HV: 15 kV
Counts per spectrum: 20000 – 25000 Current: 142.6 nA
03.05.2012 35

36. Spectrum imaging of iron oxides
Advanced analysis options
BSE image of iron ore pellet Area spectra
Silicate
Haematite Magnetite
03.05.2012 36

37. Spectrum Imaging of Iron Oxides
Autophase
Autophase result
Class Area fraction (%)
Magnetite 86.3
Haematite 9.2
Silicate 3.3
Unassigned 1.2
Total 100.0
Magnetite / Haematite = 9.4
03.05.2012 37

38. Classification of iron oxides
Feature analysis
BSE image of iron ore pellet 15 kV, ~450 kcps, 0.5 s
Magnetite Haematite
Ti-Haematite Ti-Magnetite
03.05.2012 38

39. Quantification with hybrid method
Standardless with reference for Fe and O
Class Count Area fraction (%)
Ti-Magnetite 2 0,1
Magnetite 540 79,7
Ti-Haematite 2 0,1
Haematite 57 8,3
Quartz 3 0,6
Olivine 11 1,6
Na-feldspar 4 5,6
Alumosilicate 3 0,1
Calcium pyroxene 1 0,1
Apatite 2 2,1
Calcium carbonate 2 0,3
Unclassified 26 1,4
All 653 100,0
Magnetite / Haematite = 9.6 (Autophase 9.4)
03.05.2012 39

40. Summary
• State-of-the-art XFlash® SDD technology enables fast mapping
• Spectrum imaging significantly enhances EDS analysis
• Deconvolution is an important tool for element identification
and quantification
• Computer-controlled acquisition provides high resolution at the
macroscale
• Feature analysis combines morphological and chemical classification
• Hybrid method combines standardless and standard-based
quantification
03.05.2012 40

41. Geological Applications of the
M4 TORNADO µ-XRF Spectrometer
Dr. Roald Tagle, µ-XRF Application Scientist,
Bruker Nano GmbH, Berlin

42. A technological alliance
From electron to X-ray excitation
µ-XRF ARTAX EDS QUANTAX
High speed µ-XRF spectrometer
03.05.2012 42

43. The M4 TORNADO
Spatially resolved µ-X-ray spectroscopy
03.05.2012 43

44. The M4 TORNADO
Focusing X-rays with a polycapillary lens
Focusing X-rays
23 µm for 17,5 keV
10 mm
Poly-capillary lens collects large angle of
tube radiation and concentrates it into a
small spot on the sample
03.05.2012 44

45. The M4 TORNADO
Instrument specifications
Key Features
• High brilliance X-ray source with
small spot
• Video microscope for sample
positioning with 10X and 100X
magnification
• SDD technology offering high
count rate capability in
combination with optimum
energy resolution
• Large vacuum chamber,
SDD 30 mm2, 20 mbar in 120 s
<145 eV FWHM
• Powerful high speed servo
motors, for samples up to 5 kg
03.05.2012 45

46. Comparison µ-XRF & electron excitation
High sensitivity for heavy elements
• Spectra of NIST 612 with approx. 500 ppm of more than 20 elements,
EPMA (blue) and µ-XRF (red)
• Different excitation probability, therefore higher sensitivity for heavy elements
03.05.2012 46

47. Features and applications examples of
the M4 Tornado in geology
• Qualitative and quantitative analyses of large samples, up to
30 X 15 cm and 5 kg, without previous preparation
 Element distribution in sediments (K/Pg-boundary)
 Documenting thin sections (large area scan)
 Composition of the unique Dermbach meteorite
(HyperMap quantification)
• Quantitative analysis for mayor and trace elements, down to
the low ppm range
 Composition of volcanic glasses
03.05.2012 47

48. K-Pg boundary
Asteroid impact and mass extinction
Chicxulub impact structure
• ~Ø 180 km, ~65 Ma
• Target rock:
silicate basement,
3 km sediments
Chicxulub
crater
Yax-1
UNAM-7
Image of NASA Worldwind
Raton Basin continental K/Pg sites
03.05.2012 48

49. Scan of the Cretaceous / Paleogene
boundary in Raton Basin US
Optimized for
Overview measurement trace elements
Pg
K
Ni/Si Cr/Si Zr/Si
Ca Al Cr Cr
5 mm
03.05.2012 49

50. Scanning thin sections
Document thin sections or samples Conditions:
in a short time e.g. ~ 30 minutes per 35 keV 800 µA,
section up to 18 at the same time! 5 ms per pixel
100 µm step size
Results can
be saved in
independent
files.
03.05.2012 50

51. Independently saved section results
03.05.2012 51

52. Qualitative and quantitative analysis
of the unique Dermbach iron meteorite
The Dermbach meteorite was found in Germany in 1924.The Fe-Ni phase contains
one of the highest Ni-concentrations described in literature
Conditions:
50 keV 200 µA,
5 ms per pixel
60 µm step size
974 x 883 Pixel
2 h measuring
time
The HyperMap feature allows an optimal “data mining”!
Not only compositional overview for recognition of characteristic areas
but also quantification of selected regions
Bartoschewitz et al (2012). LPSC. Abs 1292
03.05.2012 52

53. Qualitative and quantitative analysis
of the unique Dermbach iron meteorite
Fe Co Ni Cu
Ni-low 1 70.2 1.11 28.5 0.22
Ni-low 2 65.0 1.08 33.6 0.29
Ni-high 1 58.8 0.96 40.4 0.44
Ni-high 2 55.8 0.95 42.7 0.48
Results
• The high Ni concentrations were
confirmed. A strong fractionation of the
Fe-Ni-metal with a low-Ni rim could be
found in the sample
• The Ni increase correlates with the Cu
increase in the Fe-Ni metal
03.05.2012 53

54. Quantitative analysis of major and trace
elements in volcanic glass
The quantification was
performed using the
M4 standardless
quantification routine.
35 kV, 750 µA, 60 s
Al/Ti/Cu-filter
Ga ~20 ppm
Sr from 30 to 120 ppm
03.05.2012 54

55. Summary
• Unique speed and performance in the determination of the element
distribution in large sample with measurement times per pixel of 0.3 ms
and up to 4 Million pixels in a single HyperMap
• High spatial resolution down to 25 µm X-ray spot size, motors steps of 4
µm
• Optimal for the analysis of inhomogeneous samples, due to better
identification of the representative location of interest
• Non-destructive, fast analysis of large samples without preparation,
including solid, powder or liquid samples
• Qualitative and quantitative analysis of all elements from Na upwards, due
to vacuum chamber, detection limit for heavy trace elements in the low
ppm range
• Standardless Fundamental Parameter quantification with type calibration
option
• Powerful software with multiple tools for optimal data mining
03.05.2012 55

56. Natural History Museum of Natural Institute of Universidad
Museum London History, HU Berlin Meteoritics, Nacional Autónoma
University of de México
A. Kearsley D. Stöffler, P. Claeys, New Mexico
L. Hecht J. Urrutia-
H. Newsom Fucugauchi
Institute for Geozentrum International Ocean Drilling
Planetology, Nordbayern Continental Scientific Program
WWU Münster Drilling Program
P. Schulte
A. Deutsch
03.05.2012 56

57. Innovation with Integrity
Copyright © 2012 Bruker Corporation. All rights reserved. www.bruker.com

58. Sample Classification
03.05.2012 59

59. BSE Ca Si Fe Na
03.05.2012 60

60. BSE Ca Si Fe Na
03.05.2012 61

61. BSE Ca Si Fe Na 2 mm
03.05.2012 62

62. Feature analysis
Baddeleyite (ZrO2) at lunar meteorite
Automated particle search
• Binarization of BSE image
(Grayscale thresholds: 180-255)
• Morphological filtering
(>3µm lengths, >2 µm widths)
• Chemical classification
(Zr >55 wt.%%) 2 mm
Composite BSE image of Dhofar 287A (9x5 mm)
03.05.2012 63

63. Feature analysis
Baddeleyite (ZrO2) at lunar meteorite
Automated particle search
• Binarization of BSE image
(Grayscale thresholds: 180-255)
• Morphological filtering
(>3µm lengths, >2 µm widths)
• Chemical classification
(Zr >55 wt.%%) 2 mm
Composite BSE image of Dhofar 287A (9x5 mm)
• 90 images scanned
• 997 grains analyzed
in 86 min
• 11 baddeleyite grains
were detected
6 µm
03.05.2012 64

64. Measurement on a fish fossil from
Solnhofen limestone
Conditions
50 keV 600 µA
1618x462 pixels
40 ms per pixel
40 µm step size
10h meas. Time
747516 single
spectra
Mosaic image of the sample
Total x-ray intensity
03.05.2012 65

65. Measurement on a fish fossil from
Solnhofen limestone
Fe P 1 cm
03.05.2012 66

66. M4 TORNADO
High-end µ-XRF spectrometer
Complete instrument Additional options
• Second tube with
collimator e.g. W-anode
for optimal detection
heavy elements in trace
concentration like Ag, Cd
580 mm
or Pd.
• Second detector for
faster data acquisition
03.05.2012 67