A budget of the Himalayan orogenesis on the Global Carbon Cycle

The India-Asia collision induces major topographic and drainage evolutions at continental scale. As a consequence, dynamics of processes which control the carbon cycle are strongly modified. The development of the Himalayan basin generates major erosion fluxes that, through silicate weathering and organic carbon burial, tend to consume atmospheric CO2. Conversely, several processes tend to release CO2 to the atmosphere. This includes processes poorly documented such as CO2 degassing due to metamorphism of carbonated formations or oxidation of fossil organic carbon during erosion. In this synthesis we review the major processes involved and the present quantification that can be measured on the modern Himalayan basin or deduced from sedimentary archives.