black beauty: unique martian meteorite – a match for ......martian meteorites. multiple igneous...
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Black Beauty: Unique Martian Meteorite – a Match for Average Martian Crust
Carl B. Agee
Institute of Meteoritics and Dept. Earth and Planetary Sciences, Univ. New Mexico
NWA 7034 Martian Meteorite (Basaltic Breccia), Single Stone, 320 grams, find: Western Sahara 2011, shown also two pairings of “Black Beauty”
Agee, 8th Mars Conference
Agee, 8th Mars Conference
Western Sahara
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NWA 7034 “Pairing Group” includes: NWA 7034 NWA 7475 NWA 7533 (Humayun et al. 2013) NWA 7906 NWA 8114 NWA 8171 These are all stones from the same meteoroid. Total known weight ~1.5 kg
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HOWARDITE NWA 6817
LUNAR FELDSPATHIC BRECCIA
NWA 2995
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Igneous Clasts
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Secondary Alteration Objects
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Numerous spherules throughout: micron to centimeter scale
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Mineralogy of NWA 7034 (n=18)
Plagioclase Feldspar Alkali Feldspar Pyroxenes (3) Magnetite Maghemite Ilmenite Ferrihydrite Clay minerals (phyllosilicate) Cl-rich apatite Chromite Pyrite Merrillite Rutile Zircon Baddelyite Olivine
Red=Fe Blue=Al Green=Mg
6mm
Agee, 8th Mars Conference
Mineralogy of NWA 7034 (n=18)
Plagioclase Feldspar Alkali Feldspar Pyroxenes (3) Magnetite Maghemite Ilmenite Ferrihydrite Clay minerals (phyllosilicate) Cl-rich apatite Chromite Pyrite Merrillite Rutile Zircon Baddelyite Olivine
6mm
WATER BEARING
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Mineralogy of NWA 7034 (n=18)
Plagioclase Feldspar Alkali Feldspar Pyroxenes (3) Magnetite Maghemite Ilmenite Ferrihydrite Clay minerals (phyllosilicate) Cl-rich apatite Chromite Pyrite Merrillite Rutile Zircon Baddelyite Olivine
6mm
U-Pb AGE DATING
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NWA 7034 Bulk Composition Matches “Martian Crust” from Rover and Orbiter
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Black Beauty Breccia: Mars Geological Field Area Contained in a Hand Sample
(see Santos et al. Poster)
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Cartwright et al. (EPSL, 2014)
Martian Atmosphere in NWA 7043
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Cartwright et al. (EPSL, 2014)
Martian Atmosphere in NWA 7043
Argon in Black Beauty similar to Curiosity values
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Oxygen Isotopes
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Rb-Sr: 2.1 Ga formation age of NWA 7034: Early Amazonian Mars
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Sm-Nd : 4.4 Ga formation age of NWA 7034: Early Noachian Mars
Nyquist et al. 2013 Agee, 8th Mars Conference
Zircon ages: ~1.5 and 4.4 billion years
Scale: 1-inch round thin section
*~4.4 Ga zircon ages in Black Beauty were first reported by Humayun et al., Nature, 2013.
Agee, 8th Mars Conference
Agee, 8th Mars Conference
Aqueous alteration of near surface materials on Mars: Early Amazonian Epoch, Early Noachian?
NWA 7034 has extraterrestrial δD and up to ~6000 ppm indigenous (martian) water. (shergottites have ~100’s ppm)
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Which minerals harbor the ~6000 ppm water in NWA 7034?
1% Phyllosilicate = 1900 ppm
1-2% Ferrihydrite = 1100 ppm
BF STEM image showing fine-crystalline matrix
HRTEM image of detected phyllosilicate
BSE image of Fe-oxide rich spherule
5% Maghemite = 1000 ppm
5% Cl-rich Apatite = 150 ppm
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Permafrost on northeastern Spitsbergen, Svalbard
Arctic plains of northern Mars on May 25, 2008 Impact induced?
Where did the water in NWA 7034 come from?
Volcano induced?
Early Amazonian? Agee, 8th Mars Conference
Early Noachian?
Credits: Kevin Gill
SURFACE WATER
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X-ray Tomography, 2.2 micron voxels Doug Rowland (UC Davis)
“Black Beauty” expands our understanding of Mars from studies of Martian meteorites. Multiple igneous rock types from Noachian. Secondary alteration materials show rock interaction with the Martian hydrosphere. Black Beauty is first meteorite that resembles rocks that rovers are sampling in outcrop on Mars.
Agee, 8th Mars Conference