The marine reservoir effect (MRE) affects radiocarbon dating because the carbon consumed by organisms like shellfish in the ocean is older than the organism and further complications occur from the geographical location and make-up where the organism lived.
Adapted from Alves, E. Q., Macario, K., Ascough, P., & Bronk Ramsey, C. (2018). The worldwide marine radiocarbon reservoir effect: Definitions, mechanisms, and prospects. Reviews of Geophysics, 56, 278–305.
