Seismicity generated from the Chicxulub impact has been postulated as the cause for the dramatic alteration of basin margin morphology and catastrophic movement of sediments in the Gulf of Mexico (GOM). Immediately following the impact, the formation of the Cretaceous-Paleogene boundary deposit (KPBD) was widespread and caused considerable erosion as portions of the Florida Escarpment collapsed, inducing sediment failure on the northern Florida Platform and formation of the ancestral De Soto Canyon. Overlying the more prominent KPBD existed a distinct, younger, post-Cretaceous/Paleogene carbonate slope deposit (CSD) confined within the De Soto Canyon bathymetric feature. Presence of this discrete unit provided insight into the post-impact history of De Soto Canyon and its long-duration connection to the Suwannee Strait, which linked the GOM with the Atlantic Ocean for almost 40 ma. We have postulated that the bathymetric low of the De Soto Canyon acted as a conduit for west to east sediment movement from nearby carbonate-dominated shorelines into the canyon in episodic sediment transport events from the Danian to the earliest Miocene. Closure of the Suwannee Strait, due to sediment infilling, terminated deposition of the De Soto Canyon CSD. This was followed by major siliciclastic influx as the paleo-Tennessee drainage system began to enter the Mississippi Canyon area.