Paleo-redox fronts and their formation in carbonate mound sediments from the Rockall Trough

► The impact of diagenesis on carbonate mound sediments varies among core intervals. ► An interval with minima in magnetic susceptibility is topped by iron rich sediments. This is overlain by a lithified interval, low in aragonite. ► This succession formed during times of a fixed redox boundary in the sediment. ► The associated lithification pre-dates erosional processes.