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• W2012348468 abstract "Initial 187Os/188Os isotopic compositions for geochronologically and geologically well -constrained 3.8-Ga spinel peridotites from the Itsaq Gneiss Complex of southern West Greenland and chromite separates from 3.46-Ga komatiites from the Pilbara region of Western Australia have been determined to investigate the osmium isotopic evolution of the early terrestrial mantle. The measured compositions of 187Os/188Os(0) = 0.10262 ± 2, from an olivine separate, and 0.10329 ± 3, for a spinel separate from ∼3.8-Ga peridotite G93/42, are the lowest yet reported from any terrestrial sample. The corrections for in situ decay over 3.8 Ga for these low Re/Os phases are minimal and change the isotopic compositions by only 0.5 and 2.2% for the spinel and the olivine, respectively, resulting in 187Os/188Os(3.8 Ga) = 0.1021 ± 0.0002 and 0.1009 ± 0.0002, respectively. These data extend direct measurement of Os isotopic compositions to much earlier periods of Earth history than previously documented and provide the best constraints on the Os isotopic composition of the early Archean terrestrial mantle. Analyses of Pilbara chromites yield 3.46-Ga mantle compositions of 0.1042 ± 0.0002 and 0.1051 ± 0.0002. These new data, combined with published initial Os isotopic compositions from late Archean and early Proterozoic samples, are compatible with the mantle, or at least portions of it, evolving from a solar system initially defined by meteorites to a modern composition of 187Os/188Os(0) = 0.1296 ± 0.0008 as previously suggested from peridotite xenolith data ( Meisel et al., 2001); the associated 187Re/188Os(0) = 0.435 ± 0.005. Thus, chondritic 187Os/188Os compositions were a feature of the upper mantle for at least 3.8 billion years, requiring chondritic Re/Os ratios to have been a characteristic of the very early terrestrial mantle. In contrast, nonchondritic initial compositions of some Archean komatiites demonstrate that Os isotopic heterogeneity is an ancient feature of plume materials, reflecting the development of variable Re/Os mantle sources early in Earth history. The lower average 187Os/188Os = 0.1247 for abyssal peridotites (Snow and Reisberg, 1995) indicate that not all regions of the modern mantle have evolved with the same Re/Os ratio. The relative sizes of the various reservoirs are unknown, although mass balance considerations can provide some general constraints. For example, if the unradiogenic 187Os/188Os modern abyssal peridotite compositions reflect the prevalent upper mantle composition, then the complementary high Re/Os basaltic reservoir must represent 20 to 40% by mass of the upper mantle (taken here as 50% of the entire mantle), depending on the mean storage age. The difficulties associated with efficient long-term storage of such large volumes of subducted basalt suggest that the majority of the upper mantle is not significantly Re-depleted. Rather, abyssal peridotites sample anomalous mantle regions. The existence of 3.8-Ga mantle peridotites with chondritic 187Os/188Os compositions and with Os concentrations similar to the mean abundances measured in modern peridotites places an upper limit on the timing of a late accretionary veneer. These observations require that any highly siderophile element -rich component must have been added to the Earth and transported into and grossly homogenized within the mantle by 3.8 Ga. Either large-scale mixing of impact materials occurred on very short (0–100 myr) timescales or (the interpretation preferred here) the late veneer of highly siderophile elements is unrelated to the lunar terminal cataclysm estimated to have occurred at ∼3.8 to 3.9 Ga." @default.
• W2012348468 created "2016-06-24" @default.
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• W2012348468 date "2002-07-01" @default.
• W2012348468 modified "2023-10-17" @default.
• W2012348468 title "Constraints on mantle evolution from 187Os/188Os isotopic compositions of Archean ultramafic rocks from southern West Greenland (3.8 Ga) and Western Australia (3.46 Ga)" @default.
• W2012348468 cites W1483453932 @default.
• W2012348468 cites W1528656643 @default.
• W2012348468 cites W1641514132 @default.
• W2012348468 cites W1964044365 @default.
• W2012348468 cites W1964050029 @default.
• W2012348468 cites W1969092428 @default.
• W2012348468 cites W1975777679 @default.
• W2012348468 cites W1981080939 @default.
• W2012348468 cites W1984726146 @default.
• W2012348468 cites W1984745359 @default.
• W2012348468 cites W1987907556 @default.
• W2012348468 cites W1988806251 @default.
• W2012348468 cites W1990157828 @default.
• W2012348468 cites W1993312544 @default.
• W2012348468 cites W2002193431 @default.
• W2012348468 cites W2004856555 @default.
• W2012348468 cites W2005426441 @default.
• W2012348468 cites W2006739903 @default.
• W2012348468 cites W2010084304 @default.
• W2012348468 cites W2011250343 @default.
• W2012348468 cites W2011870553 @default.
• W2012348468 cites W2018436797 @default.
• W2012348468 cites W2020131197 @default.
• W2012348468 cites W2021798270 @default.
• W2012348468 cites W2022050148 @default.
• W2012348468 cites W2028824915 @default.
• W2012348468 cites W2028862451 @default.
• W2012348468 cites W2029364414 @default.
• W2012348468 cites W2029599884 @default.
• W2012348468 cites W2029905237 @default.
• W2012348468 cites W2030142526 @default.
• W2012348468 cites W2031839367 @default.
• W2012348468 cites W2034499563 @default.
• W2012348468 cites W2034706864 @default.
• W2012348468 cites W2034765763 @default.
• W2012348468 cites W2041432132 @default.
• W2012348468 cites W2041522814 @default.
• W2012348468 cites W2044870215 @default.
• W2012348468 cites W2047164731 @default.
• W2012348468 cites W2050160780 @default.
• W2012348468 cites W2053007185 @default.
• W2012348468 cites W2055178299 @default.
• W2012348468 cites W2059432209 @default.
• W2012348468 cites W2059703220 @default.
• W2012348468 cites W2060472760 @default.
• W2012348468 cites W2064306021 @default.
• W2012348468 cites W2065371877 @default.
• W2012348468 cites W2068464003 @default.
• W2012348468 cites W2070349829 @default.
• W2012348468 cites W2075870555 @default.
• W2012348468 cites W2081656000 @default.
• W2012348468 cites W2082384972 @default.
• W2012348468 cites W2084322477 @default.
• W2012348468 cites W2088868264 @default.
• W2012348468 cites W2088934812 @default.
• W2012348468 cites W2089884837 @default.
• W2012348468 cites W2090717522 @default.
• W2012348468 cites W2090838037 @default.
• W2012348468 cites W2093827788 @default.
• W2012348468 cites W2136662071 @default.
• W2012348468 cites W2141236028 @default.
• W2012348468 cites W2151010548 @default.
• W2012348468 cites W2166632770 @default.
• W2012348468 cites W2316810783 @default.
• W2012348468 cites W2318210320 @default.
• W2012348468 cites W3185410211 @default.
• W2012348468 doi "https://doi.org/10.1016/s0016-7037(02)00862-1" @default.
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