Session: Earth's Deep Carbon Cycle
Date: 25 June 2012, 9:30 am - 12:30 pm
Location: Montreal, Canada
Session Co-convenors: Erik Hauri (Carnegie Institution of Washington) and Juske Horita (Texas Tech University)
The deep Earth contains multiple carbon-bearing reservoirs, but the forms, ages, sizes, and distributions of the carbon in these deep-Earth reservoirs have been only vaguely discerned, and the abundance of carbon in each reservoir is poorly known. The interface and interconnection between the surficial and deep-Earth carbon cycles include volcanoes on continents, ocean islands, mid-ocean ridges and convergent margins, and the altered oceanic crust recycled into the deep Earth at subduction zones. Volcanic eruption and degassing deliver carbon-bearing volatile compounds from the deep-Earth into the atmosphere, and the cycle is completed by returning carbon-rich organic, inorganic, and biological materials in near-surface sediments and altered oceanic crust into the Earth's interior at subduction zones. The balance of delivery and return fluxes of carbon from the surface to the interior is so poorly known that we don't even know if the net flux of carbon is into—or out of—the Earth's interior. This session invited papers describing research results from geochemistry, experimental petrology and geodynamic modeling that address these fundamental issues in the Earth's deep carbon cycle.