analysis of lunar highland regolith samples from apollo 16
TRANSCRIPT
Geological Society of America 2008
Analysis of lunar highland regolith samples from Apollo 16 drive core
64001/2 and lunar regolith simulants –an expanding comparative databasep g p
Christian M. Schrader and Doug RickmanMarshall Space Flight Center, Huntsville, AL
Douglas StoeserUnited States Geological Survey, Denver, CO
Susan Wentworth and Dave S McKaySusan Wentworth and Dave S. McKayJohnson Space Center, Houston, TX
Pieter Botha, Alan R. Butcher, Hanna E. Horsch, Aukje Benedictus, and Paul Gottlieb
Intellection in Denver, CO and Brisbane, QLD
Outline• Background of the lunar regolith
simulant effort
• Apollo site and sample selection
• Results of QEMSCAN® modal analysis of lunar material
– change in major mineral modal% with size fraction
– comparison of major/trace minerals in sieved vs. thin section samples
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Outline, cont.
• Results of analysis of simulants vs. Apollo samples
• Future, ongoing, and parallel workutu e, o go g, a d pa a e o
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In support of a future lunar outpost...• This work is part of a larger effort to compile an internally consistent
database on lunar regolith (Apollo samples) and lunar regolith simulants.
– Characterize existing lunar regolith and simulants in terms ofg g• Particle type• Particle size distribution• Particle shape distribution• Bulk density• Other compositional characteristics
Evaluate regolith simulants (Figure of Merit) by above properties by– Evaluate regolith simulants (Figure of Merit) by above properties by comparison to lunar regolith (Apollo sample)
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Apollo 16 site
LM
Station 4:64001/64002
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Station 4 samplesgeochemical data from Korotev (1982) and Korotev et al. (1984)
64002(Houck, 1982)
03.0 4.0 5.0 6.0 7.0
040 50 60 70 80 90 100 110
One thin-section64002,6019: 5.0 – 8.0 cm
Eight sieved samples
10
20
0
0
64002,262: 5.0 – 5.5 cm
64001(Basu & McKay, 1984)
30
40h, c
entim
eter
s
%FeO0
0
Is/FeO
(Basu & McKay, 1984)
One thin-section64001,6031: 50.0 – 53.1 cm
Ei h i d l
40
50
dept
h 0
0
Eight sieved samples64001,374: 52.0 – 52.5 cm
Apollo 16 core 64001/64002
60
70
Apollo 16 core 64001/64002
0
0
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Modal analysis of sieved grain mounts64002,262 sieved fractions
6060
70
64001,374 sieved fractions
60
70
250-500 μm53
36
50
32
49
3429
40
50
60
dal%
250-500 μm90-150 μm45-75 μm<20 μm
54
34
51
36
45
31
48
40
50
60
dal%
μ90-150 μm45-75 μm<20 μm
3 13 14
1
29
2 110
20
30mod
613 1
51
25
210
20
30mo
3 13 1 12 10
Plagioclase Pyroxene Olivine Glass
13 1 12 00
Plagioclase Pyroxene Olivine Glass
As size decreases, glass modal% increases at the expense of mineral modal%.
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Change in modal% by size fraction: 64002,262
64002, 2622.5
1.0
1.5
2.0
ion/
inte
grat
ed 250-500 μm90-150 μm45-75 μm<20 μm
0.0
0.5
Pl Opx Cpx Ol Gl
fract
i <20 μm
<20 μm fraction: All minerals are depleted relative to bulk sample: 29-43%.Glass is enriched relative to bulk sample: 30%.
All fractions: Plagioclase is increasingly depleted as grain sizedecreases. The 250-500 μm fraction is less enriched inother minerals than in the 64001 sample.
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Change in modal% by size fraction: 64001,374
64001, 3742.5
1.0
1.5
2.0
ion/
inte
grat
ed 250-500 μm90-150 μm45-75 μm<20 μm
0.0
0.5
Pl Opx Cpx Ol Gl
fract <20 μm
<20 μm fraction: All minerals are depleted relative to bulk sample: 32-56%.Glass is enriched relative to bulk sample: 17%.
All fractions: Plagioclase, pyroxenes, and olivine are increasinglydepleted as grain size decreases.
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Modal analysis: thin sections versus integrated bulk grain mountsbulk grain mounts
• Minerals report as higher in thin section than in corresponding integrated
60
corresponding integrated grain mounts.– Edge effects/mixed
phases in thin sections
44 4440
4643
46
36
4140
50 64002, 6019 (TS)64002, 262 (GM)64001, 6031 (TS)64001 374 (GM) phases in thin sections
report as minerals?– Real effect from missing
fractions in grain mounts?20
30
mod
al% 64001, 374 (GM)
– Sampling error from sieving?
313 1
31
31
0
10
• Glass shows less regular pattern.
Plagioclase Pyroxene Olivine Glass
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Modal analysis: thin sections versus integrated b lk i tbulk grain mounts
• Trace Minerals:0.40
– Given, the very low amounts of some trace
i l (<0 01
0.30
0.3564002, 6019 (TS)64002, 262 (GM)64001, 6031 (TS) minerals (<0.01
modal%), the consistency is encouraging.0.15
0.20
0.25
mod
al%
64001, 6031 (TS)64001, 374 (GM)
g g
– Some of these are especially important to 0.05
0.10
In Situ Resource Utilization (ISRU) on the moon.
0.00
Ilmenite Ap/Whit. Native Fe Spinels Troilite
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Unclassified material in QEMSCAN® modal analysis
The modal% of unclassified material:
20
25
30
dal%
)64002,26264001,374
– ranges from ~5-24% in any one analysis;10
15
20
clas
sifie
d (m
od
– tends to increase as size fraction decreases in grain mounts;
0
5
050100150200250300350400
Middle of size bin (μm)
unc
mounts;
– is higher in integrated grain mounts than in thin sections
Middle of size bin (μm)
Thin sections64002,6019: 6.6% unclassified64001 6031: 6 4% unclassified
• (is more material misclassified due to edge effects and phase mixing?)
• (is this from another
64001,6031: 6.4% unclassified
Integrated grain mounts64002,262: 8.4% unclassified64001 374 16 9% l ifi d
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• (is this from another, unknown effect?)
64001,374: 16.9% unclassified
Lunar simulants: Mare and HighlandsNU-LHT-1M lunar highlands simulant
JSC-1A lunar mare simulant
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simulant
Overview: Major mineral modal comparison between simulants and 64001/64002between simulants and 64001/64002
67
5460
70
64001/2 TS Avg. 5360
7064001/2 TS Avg.JSC-1
44 45
54
45 44
40
50
mod
al%
64001/2 TS Avg.NU-LHT-2MNU-LHT-1MOB-1
44 45
35 3439
29
5253
3835
30
40
50JSC-1AJSC-1AFFJS-1MLS-1
3
10 10 1013
5
25
3510
20
30m
3
12 141612
17
8
1922
58
17
10
20
30
313
0
Plagioclase Pyroxene Olivine Glass
31 1
0
Plagioclase Pyroxene Olivine Glass
Highland simulants Mare simulants
We are incorporating particle type data (e.g., the presence of agglutinates) and phase chemistry into these comparisons.
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agglutinates) and phase chemistry into these comparisons.
Overview: Trace mineral modal comparison between simulants and 64001/64002between simulants and 64001/64002
0.40
0.45
64001/2 TS Avg.0.40
0.4564001/2 TS Avg.JSC-1
0 20
0.25
0.30
0.35
mod
al%
64001/2 TS Avg.NU-LHT-2MNU-LHT-1MOB-1
0 20
0.25
0.30
0.35 JSC-1AJSC-1AFFJS-1MLS-1
0.05
0.10
0.15
0.20m
0.05
0.10
0.15
0.20
Highland simulants Mare simulants
0.00
Ilmenite Ap/Whit. Native Fe Spinel Sulfides0.00
Ilmenite Ap/Whit. Native Fe Spinel Sulfides
Highland simulants Mare simulants
We are incorporating particle type data (e.g., the presence of agglutinates) and phase chemistry into these comparisons.
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agglutinates) and phase chemistry into these comparisons.
Further and ongoing work• Continue to analyze Apollo samples by total phase
modal%.• Incorporate particle type modal analysis by determining
which phases are present in lithics, breccias, l ti t tagglutinates, etc.
• Incorporate phase chemistry.
• Analyze simulants by these same techniques for y y qcomparison by Figure of Merit algorithms.
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Parallel workParallel work
Characterizing particle size and shapeCharacterizing particle size and shape distributions and bulk densities of lunar regolith and simulants for comparison byregolith and simulants for comparison by FoM.
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References
Basu, A. and Mckay, D.S., “Petrologic Profile of Apollo 16 Regolith at Station 4”, Proceedings of the 15th Lunar and Planetary Science Conference, Part 1, Journal of Geophysical Research, Vol. 89, Supplement, 1984, pp. C133-C142.
Houck, K.J., “Modal Petrology of Six Soils from Apollo 16 Double Drive Tube 64002”, Proceedings of the 13th Lunar and Planetary Science Conference, Part 1, Journal of Geophysical Research, Vol. 87, Supplement, 1982b, pp. A210-A220.
Korotev, R.L., “Comparative Geochemistry of Apollo 16 Surface Soils and Samples from Cores 64002 and 60002 through 60007”, Proceedings of the 13th Lunar and Planetary Science Conference, Part 1, Journal of Geophysical Research, Vol.. 87, Supplement 1982 pp A269 A278Supplement, 1982, pp. A269-A278.
Korotev, R.L., Morris, R.V., and Lauer, H.V., Jr., “Stratigraphy and Geochemistry of the Stone Mountain Core (64001/2)”, Proceedings of the 15th Lunar and Planetary Science Conference, Part 1, Journal of Geophysical Research, Vol. 89, Supplement, , , p y , , pp ,1984, pp. C143-C160.
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