Studies of Kamacite, Perryite and Schreibersite in E-Chondrites and Aubrites
Abstract
The bulk composition of metal (kamacite plus perryite) was determined in eleven E-chondrites and eight aubrites. The data are compatible with the subdivision of the E-chondrites into two groups (Yavnel, 1963; Anders, 1964), St Mark's and St Sauveur belonging to type I (Easton, 1985). The Ni content of kamacite plus perryite in Kota Kota (5.49 percent) is within the range covered by the remaining E-chondrites. Normative perryite constitutes 2.1 percent of Kota Kota and 2.7 percent of South Oman. The Ni content in the bulk metal of Aubres, Bishopville, Norton County and Pena Blanca Spring is about half the average Ni content in the metal of E-chondrites or the remaining aubrites (Bustee, Khor Temiki, Mayo Belwa and Shallowater). High Ga/Ni ratios distinguish the metal in E-chondrites and aubrites from that in ordinary chondrites. The composition of both bulk metal and individual grains in aubrites makes it unlikely that they represent residual metal trapped during magmatic differentation and/or fractional crystallization of E6 material. Compositional differences between metal grains strongly indicate that the aubrites are polymict breccias.
- Publication:
-
Meteoritics
- Pub Date:
- March 1986
- DOI:
- 10.1111/j.1945-5100.1986.tb01227.x
- Bibcode:
- 1986Metic..21...79E
- Keywords:
-
- Chondrites;
- Kamacite;
- Meteoritic Composition;
- Schreibersite;
- Breccia;
- Chemical Composition;
- Grain Size;
- Nickel;
- Trace Elements;
- METEORITES;
- E CHONDRITES;
- AUBRITES;
- STONY METEORITES;
- SAMPLES;
- METEORITE;
- ACHONDRITES;
- KAMACITE;
- PERRYITE;
- SCHREIBERSITE;
- MINERALOGY;
- MINERALS;
- COMPOSITION;
- METAL;
- CLASSIFICATION;
- MAJOR ELEMENTS;
- DISTRIBUTION;
- SILICON;
- TRACE ELEMENTS;
- GALLIUM;
- GERMANIUM;
- NICKEL;
- ELEMENT RATIOS;
- AUBRES;
- GRAINS;
- KHOR TEMIKI;
- SHALLOWATER;
- PHOTOMICROGRAPHS;
- COBALT;
- MAYO BELWA;
- CATALOG;
- Lunar and Planetary Exploration; Meteorites;
- Mineralogical Studies