“…Altered oceanic crust Crustal carbon concentration, subduction zone length, subduction rate - Müller et al, 2016;Müller and Dutkiewicz, 2018 Serpentinized mantle Serpentinite carbon concentration and extent, subduction zone length, subduction rate 681 ± 45 ppm (average serpentinite carbon concentration); 20 ± 10%, 13.5 ± 1.5 km (serpentinization degree and extent) Kelemen and Manning, 2015;Müller et al, 2016;East et al, 2019 Carbonate sediment Subducted carbonate sediment - Dutkiewicz et al, 2018 Continental rifts Rift length, average rift carbon flux 2.5 ± 2.0 kt C km −1 yr −1 (rift carbon length flux) Müller et al, 2016;Brune et al, 2017;Hunt et al, 2017 Mid-ocean ridges Mid-ocean ridge length, present-day mid-ocean ridge carbon flux 0.37 ± 0.23 kt C km −1 yr −1 (ridge carbon length flux) Müller et al, 2016 Plume volcanoes LIP area, basalt carbon concentration 6.0 ± 3.0 Mt C yr −1 (baseline plume flux); 0.8 ± 0.3 wt% (primary plume basalt CO 2 concentration) Müller et al, 2016;Johansson et al, 2018;Hauri et al, 2019;Werner et al, 2019 Arc volcanoes Subduction zone length, carbonate platform distribution, present-day arc flux, expected carbonate-intersecting and non-carbonate-intersecting volcanic carbon fluxes 27 ± 16 Mt C yr −1 (present-day arc flux); 10 7.4−8.0 mol km −1 yr −1 (range for carbonate-intersecting arcs); 10 0.0−6.4 mol km −1 yr −1 (range for non-carbonate-intersecting arcs) Kelemen and Manning, 2015;Müller et al, 2016;Pall et al, 2018;Werner et al, 2019 Input data in italics are provided by GPlates modeling. Density of basaltic rock is taken as 2800 kg m −3 .…”