Carbon, oxygen and nitrogen isotopic compositions of possible martian weathering products in EETA 79001

Journal Article · Fri Apr 01 04:00:00 EST 1988 · Geochimica et Cosmochimica Acta; (USA)

DOI:https://doi.org/10.1016/0016-7037(88)90362-6· OSTI ID:5181138

Wright, I P; Grady, M M; Pillinger, C T ^[1]

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1. Open Univ., Milton Keynes (England)

Carbon and oxygen isotopic analyses of carbonate-rich white-druse material isolated from a contact between lithologies A and C of the EETA 79001 shergottite indicate that this component is probably extraterrestrial in origin, and not simply an Antarctic weathering product. The {delta}{sup 13}C(+6.8{per thousand}) and {delta}{sup 18}O (+21.1{per thousand}) values of the calcium carbonate (predominantly calcite) are unlike {delta}{sup 13}C/{delta}{sup 18}O combinations of most common terrestrial carbonates (whether biogenic or abiogenic). However, {delta}{sup 13}C and {delta}{sup 18}O of the carbonates in EETA 79001 are very similar to the corresponding values for carbonates analyzed from Nakhla (a meteorite closely allied to shergottites). It seems apparent that the carbonate minerals in these SNC meteorites were formed on the meteorites' parent body (Mars ). Isotopic analysis of nitrogen liberated during combustion of a carbonate-rich fraction of EETA 79001 does not give any clear evidence for the {sup 15}N-enriched component isolated from EETA 79001 lithology C glass and postulated as trapped martian atmosphere. However, substantial amounts of nitrogen were present; the origin of these components is unclear but the low temperature of release poses some constraints.

• OSTI ID: 5181138
• Journal Information: Geochimica et Cosmochimica Acta; (USA), Journal Name: Geochimica et Cosmochimica Acta; (USA) Vol. 52:4; ISSN GCACA; ISSN 0016-7037
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
ALKALINE EARTH METAL COMPOUNDS
ANTARCTIC REGIONS
ANTARCTICA
CALCITE
CALCIUM CARBONATES
CALCIUM COMPOUNDS
CARBON 13
CARBON COMPOUNDS
CARBON ISOTOPES
CARBONATE MINERALS
CARBONATES
CHEMICAL COMPOSITION
CHEMISTRY
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
GEOCHEMISTRY
INCLUSIONS
ISOTOPE RATIO
ISOTOPES
LIGHT NUCLEI
LITHOLOGY
MARS PLANET
METEORITES
MINERALOGY
MINERALS
NITROGEN 15
NITROGEN ISOTOPES
NUCLEI
ODD-EVEN NUCLEI
ORIGIN
OXYGEN 18
OXYGEN COMPOUNDS
OXYGEN ISOTOPES
PLANETARY EVOLUTION
PLANETS
POLAR REGIONS
SOLAR SYSTEM EVOLUTION
STABLE ISOTOPES
WEATHERING