Ureilites: Trace element clues to their origin

Marie Josée Janssens, Jan Hertogen, Rainer Wolf, Mitsuru Ebihara, Edward Anders

Research output: Contribution to journalArticle

28 Citations (Scopus)

Abstract

Carbonaceous vein separates from Kenna and Haverö, as well as bulk Kenna, were analyzed by RNAA for Ag, Au, Bi, Br, Cd, Cs, Ge, In, Ir, Ni, Pd, Os, Rb, Re, Sb, Se, Te, Tl. U, and Zn. The data are reviewed together with four earlier Chicago analyses of bulk ureilites. Linear regressions confirm the presence of two metal components, with the following Cl-normalized ratios: Ir/Ni = 14.6, ≤ 1; Ge/Ni = 5.4, 2.4; Au/Ni = 2.3, 0.9. The high-Ir component is enriched in vein separates and hence belongs to veins; the lowIr component belongs to the ultramafic rock. Vein material is enriched in all elements analyzed by us except Zn, and accounts for most of the C, noble gases, and presumably siderophiles in the meteorite. Most of the properties of ureilites apparently can be explained by the cumulate model of Berkley et al. (1980), with certain modifications. Comparison of ureilites with three other ultramafic rocks from different planets (Earth's mantle, lunar dunite, and Chassigny) suggests that the ureilite parent body had a primitive chondritic composition, similar to C3V chondrites but richer in metal and carbon. It melted, causing depletion of incompatibles to a mean abundance of ~0.02 × Cl and incomplete segregation of metal, FeS, and C. Fractional crystallization or melting of metal in the presence of S and C apparently can explain the fractionations of Ir, Re, Ni, Au, and perhaps Ge, obviating the need for extraneous sources of vein metal or unusual parent-body compositions. Noble gases from the parent material may have been retrapped in carbon during magmatism, provided the system was closed.

Original languageEnglish
Pages (from-to)2275-2283
Number of pages9
JournalGeochimica et Cosmochimica Acta
Volume51
Issue number9
DOIs
Publication statusPublished - 1987 Jan 1
Externally publishedYes

Fingerprint

Trace Elements
Metals
trace element
metal
Noble Gases
noble gas
parent body
ultramafic rock
Carbon
ureilite
lunar mantle
Rocks
Meteorites
dunite
carbon
Planets
Fractionation
parent material
cumulate
Crystallization

ASJC Scopus subject areas

  • Geochemistry and Petrology

Cite this

Ureilites : Trace element clues to their origin. / Janssens, Marie Josée; Hertogen, Jan; Wolf, Rainer; Ebihara, Mitsuru; Anders, Edward.

In: Geochimica et Cosmochimica Acta, Vol. 51, No. 9, 01.01.1987, p. 2275-2283.

Research output: Contribution to journalArticle

Janssens, MJ, Hertogen, J, Wolf, R, Ebihara, M & Anders, E 1987, 'Ureilites: Trace element clues to their origin', Geochimica et Cosmochimica Acta, vol. 51, no. 9, pp. 2275-2283. https://doi.org/10.1016/0016-7037(87)90280-8
Janssens, Marie Josée ; Hertogen, Jan ; Wolf, Rainer ; Ebihara, Mitsuru ; Anders, Edward. / Ureilites : Trace element clues to their origin. In: Geochimica et Cosmochimica Acta. 1987 ; Vol. 51, No. 9. pp. 2275-2283.
@article{f3192c8195e34194abc3139e55cd053e,
title = "Ureilites: Trace element clues to their origin",
abstract = "Carbonaceous vein separates from Kenna and Haver{\"o}, as well as bulk Kenna, were analyzed by RNAA for Ag, Au, Bi, Br, Cd, Cs, Ge, In, Ir, Ni, Pd, Os, Rb, Re, Sb, Se, Te, Tl. U, and Zn. The data are reviewed together with four earlier Chicago analyses of bulk ureilites. Linear regressions confirm the presence of two metal components, with the following Cl-normalized ratios: Ir/Ni = 14.6, ≤ 1; Ge/Ni = 5.4, 2.4; Au/Ni = 2.3, 0.9. The high-Ir component is enriched in vein separates and hence belongs to veins; the lowIr component belongs to the ultramafic rock. Vein material is enriched in all elements analyzed by us except Zn, and accounts for most of the C, noble gases, and presumably siderophiles in the meteorite. Most of the properties of ureilites apparently can be explained by the cumulate model of Berkley et al. (1980), with certain modifications. Comparison of ureilites with three other ultramafic rocks from different planets (Earth's mantle, lunar dunite, and Chassigny) suggests that the ureilite parent body had a primitive chondritic composition, similar to C3V chondrites but richer in metal and carbon. It melted, causing depletion of incompatibles to a mean abundance of ~0.02 × Cl and incomplete segregation of metal, FeS, and C. Fractional crystallization or melting of metal in the presence of S and C apparently can explain the fractionations of Ir, Re, Ni, Au, and perhaps Ge, obviating the need for extraneous sources of vein metal or unusual parent-body compositions. Noble gases from the parent material may have been retrapped in carbon during magmatism, provided the system was closed.",
author = "Janssens, {Marie Jos{\'e}e} and Jan Hertogen and Rainer Wolf and Mitsuru Ebihara and Edward Anders",
year = "1987",
month = "1",
day = "1",
doi = "10.1016/0016-7037(87)90280-8",
language = "English",
volume = "51",
pages = "2275--2283",
journal = "Geochmica et Cosmochimica Acta",
issn = "0016-7037",
publisher = "Elsevier Limited",
number = "9",

}

TY - JOUR

T1 - Ureilites

T2 - Trace element clues to their origin

AU - Janssens, Marie Josée

AU - Hertogen, Jan

AU - Wolf, Rainer

AU - Ebihara, Mitsuru

AU - Anders, Edward

PY - 1987/1/1

Y1 - 1987/1/1

N2 - Carbonaceous vein separates from Kenna and Haverö, as well as bulk Kenna, were analyzed by RNAA for Ag, Au, Bi, Br, Cd, Cs, Ge, In, Ir, Ni, Pd, Os, Rb, Re, Sb, Se, Te, Tl. U, and Zn. The data are reviewed together with four earlier Chicago analyses of bulk ureilites. Linear regressions confirm the presence of two metal components, with the following Cl-normalized ratios: Ir/Ni = 14.6, ≤ 1; Ge/Ni = 5.4, 2.4; Au/Ni = 2.3, 0.9. The high-Ir component is enriched in vein separates and hence belongs to veins; the lowIr component belongs to the ultramafic rock. Vein material is enriched in all elements analyzed by us except Zn, and accounts for most of the C, noble gases, and presumably siderophiles in the meteorite. Most of the properties of ureilites apparently can be explained by the cumulate model of Berkley et al. (1980), with certain modifications. Comparison of ureilites with three other ultramafic rocks from different planets (Earth's mantle, lunar dunite, and Chassigny) suggests that the ureilite parent body had a primitive chondritic composition, similar to C3V chondrites but richer in metal and carbon. It melted, causing depletion of incompatibles to a mean abundance of ~0.02 × Cl and incomplete segregation of metal, FeS, and C. Fractional crystallization or melting of metal in the presence of S and C apparently can explain the fractionations of Ir, Re, Ni, Au, and perhaps Ge, obviating the need for extraneous sources of vein metal or unusual parent-body compositions. Noble gases from the parent material may have been retrapped in carbon during magmatism, provided the system was closed.

AB - Carbonaceous vein separates from Kenna and Haverö, as well as bulk Kenna, were analyzed by RNAA for Ag, Au, Bi, Br, Cd, Cs, Ge, In, Ir, Ni, Pd, Os, Rb, Re, Sb, Se, Te, Tl. U, and Zn. The data are reviewed together with four earlier Chicago analyses of bulk ureilites. Linear regressions confirm the presence of two metal components, with the following Cl-normalized ratios: Ir/Ni = 14.6, ≤ 1; Ge/Ni = 5.4, 2.4; Au/Ni = 2.3, 0.9. The high-Ir component is enriched in vein separates and hence belongs to veins; the lowIr component belongs to the ultramafic rock. Vein material is enriched in all elements analyzed by us except Zn, and accounts for most of the C, noble gases, and presumably siderophiles in the meteorite. Most of the properties of ureilites apparently can be explained by the cumulate model of Berkley et al. (1980), with certain modifications. Comparison of ureilites with three other ultramafic rocks from different planets (Earth's mantle, lunar dunite, and Chassigny) suggests that the ureilite parent body had a primitive chondritic composition, similar to C3V chondrites but richer in metal and carbon. It melted, causing depletion of incompatibles to a mean abundance of ~0.02 × Cl and incomplete segregation of metal, FeS, and C. Fractional crystallization or melting of metal in the presence of S and C apparently can explain the fractionations of Ir, Re, Ni, Au, and perhaps Ge, obviating the need for extraneous sources of vein metal or unusual parent-body compositions. Noble gases from the parent material may have been retrapped in carbon during magmatism, provided the system was closed.

UR - http://www.scopus.com/inward/record.url?scp=0023494544&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0023494544&partnerID=8YFLogxK

U2 - 10.1016/0016-7037(87)90280-8

DO - 10.1016/0016-7037(87)90280-8

M3 - Article

AN - SCOPUS:0023494544

VL - 51

SP - 2275

EP - 2283

JO - Geochmica et Cosmochimica Acta

JF - Geochmica et Cosmochimica Acta

SN - 0016-7037

IS - 9

ER -