Fig. 3.

Schematic diagram showing how supercontinent break-up can increase continental weathering and C deposition. Early stage of supercontinent break-up is associated with dynamic uplift and lowered sea level due to the presence of a mantle plume. Eruption of basalts increase continental weathering due to CO₂ emissions and weatherability of basalts. Lowered sea level allows the location of C burial to be dominated by oceanic crust, which will be subducted. Late stage of supercontinent break-up will generate rifted margins, which are primary environments for C burial. Late stage of supercontinent break-up will also have higher sea level due to cessation of the mantle plume. This will flood continental shelves, allowing the location of C burial to be dominated by continental shelves.