Synthesis of heavy hydrocarbons at the core-mantle boundary

Abstract

The synthesis of complex organic molecules with C-C bonds is possible under conditions of reduced activity of oxygen. We have found performing ab initio molecular dynamics simulations of the C-O-H-Fe system that such conditions exist at the core-mantle boundary (CMB). H 2 O and CO 2 delivered to the CMB by subducting slabs provide a source for hydrogen and carbon. The mixture of H 2 O and CO 2 subjected to high pressure (130 GPa) and temperature (4000 to 4500 K) does not lead to synthesis of complex hydrocarbons. However, when Fe is added to the system, C-C bonds emerge. It means that oil might be a more abundant mineral than previously thought.