| Abstract: | Rhenium and osmium abundances, and osmium isotopic compositions were measured by negative thermal ionization mass spectrometry in thirty samples, including replicates, of five IIA and eight IIB iron meteorites. Log plots of Os vs. Re abundances for IIA and IIB irons describe straight lines that approximately converge on Lombard, which has the lowest Re and Os abundances and highest 187Re/188Os measured in a IIA iron to date. The linear IIA trend may be exactly reproduced by fractional crystallization, but is not well fitted using variable partition coefficients. The IIB iron trend, however, cannot be entirely explained by simple fractional crystallization. One explanation is that small amounts of Re and Os were added to the asteroid core during the final stages of crystallization. Another possibility is that diffusional enrichment of Os may have occurred in samples most depleted in Re and Os. -from Authors |
| Genre: | Article |
| ProdID: | 70019204 |
| Citation Author: | Morgan, J. W.; Horan, M. F.; Walker, R. J.; Grossman, J. N. |
| Citation Contributing Office: | |
| Citation Datum: | |
| Citation Day: | |
| Citation Edition: | |
| Citation Editor: | |
| Citation End Page: | 2344 |
| Citation Issue: | 11 |
| Citation Keywords: | |
| Citation Language: | English |
| Citation Larger Work Title: | Geochimica et Cosmochimica Acta |
| Citation LatN: | |
| Citation LatS: | |
| Citation LonE: | |
| Citation LonW: | |
| Citation Month: | |
| Citation No Pagination: | |
| Citation Number Of Pages: | 14 |
| Citation Online Only Flag: | |
| Citation Phsyical Description: | |
| Citation Projection: | |
| Citation Public Comments: | |
| Citation Publisher: | |
| Citation Series: | |
| Citation Series Code: | |
| Citation Series Number: | |
| Citation Search Results Text: | Rhenium-osmium concentration and isotope systematics in group IIAB iron meteorites; 1995; Article; Journal; Geochimica et Cosmochimica Acta; Morgan, J. W.; Horan, M. F.; Walker, R. J.; Grossman, J. N. |
| Citation Start Page: | 2331 |
| Citation Volume: | 59 |
| Citation Year: | 1995 |
| Type: | citation/reference |
| Text: | Rhenium-osmium concentration and isotope systematics in group IIAB iron meteorites; 1995; Article; Journal; Geochimica et Cosmochimica Acta; Morgan, J. W.; Horan, M. F.; Walker, R. J.; Grossman, J. N. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| Date Other: | Sun, 1 Jan 1995 00:00 -0600 |
| Publisher: | |