Mean ¹³CO₂ production at 50 days across 59 incubations, as measured by GC-IRMS, where ¹³CO₂ represents the specific product of AOM. Incubations contained 50 mL of BML sediment and 1 mL of the electron acceptor indicated. Incubations either had no methane added (left) or 50 mL of ¹³CH4 added (right). All samples contained 0% CO₂ at Day 0. Error bars represent standard error of the mean. Control treatments contained 4 replicates, and experimental treatments contained 8-12 replicates.