Chondrules and Opaque Phases in Unequilibrated R Chondrites: A Comprehensive Assessment of Their FormationEquilibrated Rumuruti (R) chondrites record an oxygen fugacity between 0 and 3.5 log units below the fayalite-magnetite-quartz buffer, and a sulfur fugacity (fS2) 2 log units above the iron-troilite buffer. They are more than an order of magnitude more oxidized than the ordinary chondrites [1], and orders of magnitude more sulfidized than solar values. Although the R chondrites have the highest (delta)O-17 value of any meteorites, analyses of unequilibrated R chondrites indicate chondrule formation in an oxygen isotope reservoir similar to that of the ordinary chondrite chondrules. We present the relationship of the R chondrite parent body to pre-accretionary volatiles O and S based on our analyses of unequilibrated R chondrite material in two thin sections from the meteorite Mount Prestrud (PRE) 95404.
Document ID
20160002410
Acquisition Source
Johnson Space Center
Document Type
Conference Paper
Authors
Miller, K. E. (Arizona Univ. Tucson, AZ, United States)
Lauretta, D. S. (Arizona Univ. Tucson, AZ, United States)
Connolly, H. C., Jr. (Kingsborough Community Coll. Brooklyn, NY, United States)
Berger, E. L. (Jacobs Technology, Inc. Houston, TX, United States)
Domanik, K. (Arizona Univ. Tucson, AZ, United States)