Silicon Isotope Evidence Against an Enstatite Chondrite Earth

• DOI: 10.1126/science.1219509
• Publication Date: 2012-03-03T17:25:04Z
• Authors: Caroline Fitoussi; Bernard Bourdon
• Keywords: Enstatite; Chondrule; Cosmochemistry

Building Blocks of Earth formed from an explosive and energetic series collisions that accreted material over millions years. Comparisons between rocks Earth's interior more primitive extraterrestrial samples can help tease apart the composition starting material; however, discrepancies abundance certain elements or their isotope ratios often obscure origin. Fitoussi Bourdon (p. 1477 , published online 1 March) analyzed silicon isotopes a suite chondritic meteorites Moon to reconcile some previous models. By tuning accretion models account for these Si signatures, enstatite chondrites could be ruled out as sole end-member bulk Earth. Instead, heterogeneous mixture several types is likely.