Geological Stores
Global Carbon Sink Maps
Most of the earth’s carbon is geological, resulting from the formation of sedimentary carbonate rocks in the oceans and biologically derived carbon in shale, coal and other rocks.
Transfer From Geology
Carbon is stored deep in sedimentary rocks such as limestone, the two processes which lead to the release of carbon are:
- Metamorphism = when a rocks appearance and structure (texture and mineral composition) changes because of intense heat and/or pressure
- __Subduction __= when rocks are forced down into the mantle, usually at a destructive plate boundary. The oceanic crust is forced to melt, resulting in the CO2 in the magma making its way to the surface and being outgassed via a volcanic eruption.