Paleoceanographic information from submarine overflows in the vicinity of oceanic gateways is of major importance for resolving the role of ocean circulation in modulating Earth’s
climate. Earth system models are currently the favored way to study the impact of gateways
on global-scale processes, but studies on overflow-related deposits are more suitable to understand the detailed changes. Such deposits, however, had not yet been documented in outcrop.
Here, we present a unique late Miocene contourite channel system from the Rifian Corridor
(Morocco) related to the initiation of Mediterranean Outflow Water (MOW). Two channel
branches were identified consisting of three vertically stacked channelized sandstone units
encased in muddy deposits. Both branches have different channel-fill characteristics. Our
findings provide strong evidence for intermittent behavior of overflow controlled by tectonic
processes and regional climatic change. These fluctuations in paleo-MOW intermittently
influenced global ocean circulation.