Enstatite meteorites and their parent bodies

摘要: — Enstatite meteorites are highly reduced rocks that consist of major, nearly FeO-free enstatite, variable amounts metallic Fe, Ni and troilite, a host rare minerals formed under highly-reducing conditions. They comprised the EH EL chondrites aubrites. Here I discuss some their properties nature number parent bodies. Conclusions: 1. show bulk compositional differences in non-volatile major elements were established by nebular, not planetary processes. Occurrence abundant breccias among them but lack clasts (and vice versa) suggests represent two separate 2. Aubrites derived from known enstatite on same samples third meteorite body. 3. The aubrite body may have experienced collisional break-up gravitational reassembly debris into rubble-pile object. 4. source material (parent body) was probably chondrite-like composition, had higher troilite/metallic ratio, contents titanium diopside, possibly less plagioclase than chondrites. 5. Shallowater, only non-brecciated aubrite, does appear to EH, EL, or bodies either internal (igneous) external (impact) melting Instead, Shallowater be sample yet fourth 6. complex three-stage cooling history, requiring an equally mode origin: molten partly impact with solid body, followed reassembly. 7. It is unknown why melted (the bodies), others did bodies). If unipolar dynamo induction primordial T Tauri sun dominant heat heated asteroidal-sized early Solar System, then because they intermediate sizes, whereas melt much smaller larger.