Supra-canonical 26Al/27Al and the residence time of CAIs in the solar protoplanetary disk.
The canonical initial 26Al/27Al ratio of 4.5 x 10(-5) has been a fiducial marker for the beginning of the solar system. Laser ablation and whole-rock multiple-collector inductively coupled plasma-source mass spectrometry magnesium isotope analyses of calcium- and aluminum-rich inclusions (CAIs) from CV3 meteorites demonstrate that some CAIs had initial 26Al/27Al values at least 25% greater than canonical and that the canonical initial 26Al/27Al cannot mark the beginning of solar system formation. Using rates of Mg diffusion in minerals, we find that the canonical initial 26Al/27Al is instead the culmination of thousands of brief high-temperature events incurred by CAIs during a 10(5)-year residence time in the solar protoplanetary disk.
Young
Edward D
ED
Institute of Geophysics and Planetary Physics, University of California-Los Angeles, Los Angeles, CA 90095, USA. eyoung@ess.ucla.edu
Simon
Justin I
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Galy
Albert
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Russell
Sara S
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Tonui
Eric
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Lovera
Oscar
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