Isotopic composition of carbon and nitrogen in ureilitic fragments of the Almahata Sitta meteorite
Isotopic composition of carbon and nitrogen in ureilitic fragments of the Almahata Sitta meteorite
复制标题
Almahata Sitta 陨石的尿素质碎片中碳和氮的同位素组成
DOI:
10.1111/maps.12413
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发表时间:
2015
影响因子:
2.2
通讯作者:
Downes H
中科院分区:
文献类型:
--
作者:
Downes H
This study characterizes carbon and nitrogen abundances and isotopic compositions in ureilitic fragments of Almahata Sitta. Ureilites are carbon‐rich (containing up to 7 wt% C) and were formed early in solar system history, thus the origin of carbon in ureilites has significance for the origin of solar system carbon. These samples were collected soon after they fell, so they are among the freshest ureilite samples available and were analyzed using stepped combustion mass spectrometry. They contained 1.2–2.3 wt% carbon; most showed the major carbon release at temperatures of 600–700 °C with peak values of δ13C from −7.3 to +0.4‰, similar to literature values for unbrecciated (“monomict”) ureilites. They also contained a minor low temperature (≤500 °C) component (δ13C = ca −25‰). Bulk nitrogen contents (9.4–27 ppm) resemble those of unbrecciated ureilites, with major releases mostly occurring at 600–750 °C. A significant lower temperature release of nitrogen occurred in all samples. Main release δ15N values of −53 to −94‰ fall within the range reported for diamond separates and acid residues from ureilites, and identify an isotopically primordial nitrogen component. However, they differ from common polymict ureilites which are more nitrogen‐rich and isotopically heavier. Thus, although the parent asteroid 2008TC3was undoubtedly a polymict ureilite breccia, this cannot be deduced from an isotopic study of individual ureilite fragments. The combined main release δ13C and δ15N values do not overlap the fields for carbonaceous or enstatite chondrites, suggesting that carbon in ureilites was not derived from these sources.
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DOI:
--
发表时间:
2004
期刊:
Meteorit.Planet.Sci. 39
影响因子:
--
作者:
荻原成騎;重田康成;Kitajima et al.;荻原成騎;Nakashima et al.;S.Ogihara;Nakamura et al.;S.Ogihara;El Goresy et al.
通讯作者:
El Goresy et al.
影响因子:
2.2
作者:
D. Rumble;M. Zolensky;J. Friedrich;P. Jenniskens;M. Shaddad
通讯作者:
D. Rumble;M. Zolensky;J. Friedrich;P. Jenniskens;M. Shaddad
DOI:
--
发表时间:
2004
期刊:
影响因子:
--
作者:
A. Fisenko;A. Verchovsky;L. Semjonova;C. Pillinger
通讯作者:
C. Pillinger
影响因子:
64.8
作者:
I. Franchi;I. Wright;C. Pillinger
通讯作者:
C. Pillinger
DOI:
--
发表时间:
2003
期刊:
影响因子:
--
作者:
Y. Ikeda;N. Kita;Y. Morishita;M. Weisberg
通讯作者:
M. Weisberg