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

Western Sahara

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

HOWARDITE NWA 6817

LUNAR FELDSPATHIC BRECCIA

NWA 2995

Igneous Clasts

Secondary Alteration Objects

Numerous spherules throughout: micron to centimeter scale

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

WATER BEARING

U-Pb AGE DATING

NWA 7034 Bulk Composition Matches “Martian Crust” from Rover and Orbiter

Black Beauty Breccia: Mars Geological Field Area Contained in a Hand Sample

(see Santos et al. Poster)

Cartwright et al. (EPSL, 2014)

Martian Atmosphere in NWA 7043

Cartwright et al. (EPSL, 2014)

Martian Atmosphere in NWA 7043

Argon in Black Beauty similar to Curiosity values

Oxygen Isotopes

Rb-Sr: 2.1 Ga formation age of NWA 7034: Early Amazonian Mars

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.

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)

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

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

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.

Black Beauty: Unique Martian Meteorite – a Match for ......Martian meteorites. Multiple igneous...

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