Oxygen isotopes in calcium–aluminum-rich inclusions from enstatite chondrites: new evidence for a single CAI source in the solar nebula

Calcium–aluminum-rich inclusions (CAIs) from enstatite chondrites have large 16O excesses, similar to CAIs in carbonaceous and ordinary chondrites, and are also similar in morphology, mineralogy and Al–Mg isotopic systematics. These similarities provide new evidence that most CAIs might have formed in a single, restricted nebular locale and were then distributed unevenly throughout the various chondrite accretion regions.