Deep Mantle Cycling of Oceanic Crust: Evidence from Diamonds and Their Mineral Inclusions

• DOI: 10.1126/science.1209300
• Publication Date: 2011-09-16T10:37:55Z
• Authors: M. J. Walter; S. C. Kohn; D. Araujo; G. P. Bulanova; C. B. Smith; E. Gaillou; J. Wang; A. Steele; S. B. Shirey
• Keywords: Crustal recycling; Adakite; Planetary differentiation; Hotspot (geology)

A primary consequence of plate tectonics is that basaltic oceanic crust subducts with lithospheric slabs into the mantle. Seismological studies extend this process to lower mantle, and geochemical observations indicate return upper mantle in plumes. There has been no direct petrologic evidence, however, subducted crustal components from We analyzed superdeep diamonds Juina-5 kimberlite, Brazil, which host inclusions compositions comprising entire phase assemblage expected crystallize basalt under lower-mantle conditions. The inclusion mineralogies require exhumation Because diamond hosts have carbon isotope signatures consistent surface-derived carbon, we conclude deep cycle extends