Resetting, errorchrons and the meaning of canonical CAI initial 26Al/27Al values

Computer Science

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

1

Scientific paper

The difference between the precise MC-ICPMS analyses of bulk calcium-aluminum-rich inclusion (CAI) fragments (e.g., Jacobsen et al., 2008) and supra-canonical values obtained by micro-analytical techniques, e.g., laser ablation MC-ICPMS (Young et al., 2005) and SIMS (Taylor et al., 2005), at face value seems to be problematic and therefore leads many to dismiss claims of the solar system (26Al/27Al)0 greater than ~ 5 × 10-5 as spurious. Here we use mass balance calculations to quantify the importance of open system isotopic exchange during CAI evolution and show that in situ supra-canonical, in-situ canonical, and bulk canonical measurements can all exist for an individual CAI. The calculations describe mechanisms of isotopic exchange that may have occurred early (100's ka) and late (~ 1.5 Ma) in the solar nebula and much later (> 10's Ma) on parent body planetesimals. A range of possible modal mineralogies is modeled in order to populate the compositional space defined by in situ and bulk CAI measurements. In support of these simulated data we describe in situ measurements of 27Al/24Mg, 25Mg/24Mg, and 26Mg/24Mg obtained by LA-MC-ICPMS comprising core-to-rim traverses across three CV3 CAIs. The CAIs exhibit distinctive Mg isotopic zoning profiles and varying abundances of daughter products of the short-lived nuclide 26Al that are consistent with varying amounts of open system isotope exchange.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Resetting, errorchrons and the meaning of canonical CAI initial 26Al/27Al values does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Resetting, errorchrons and the meaning of canonical CAI initial 26Al/27Al values, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Resetting, errorchrons and the meaning of canonical CAI initial 26Al/27Al values will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-764705

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.