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© The Author(s), 2014. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Biogeosciences 11 (2014): 1799-1815, doi:10.5194/bg-11-1799-2014., With an extension of > 40 km2 the recently discovered Campeche cold-water coral province located at the northeastern rim of the Campeche Bank in the southern Gulf of Mexico belongs to the largest coherent cold-water coral areas discovered so far. The Campeche province consists of numerous 20–40 m-high elongated coral mounds that are developed in intermediate water depths of 500 to 600 m. The mounds are colonized by a vivid cold-water coral ecosystem that covers the upper flanks and summits. The rich coral community is dominated by the framework-building Scleractinia Enallopsammia profunda and Lophelia pertusa, while the associated benthic megafauna shows a rather scarce occurrence. The recent environmental setting is characterized by a high surface water production caused by a local upwelling center and a dynamic bottom-water regime comprising vigorous bottom currents, obvious temporal variability, and strong density contrasts, which all together provide optimal conditions for the growth of cold-water corals. This setting – potentially supported by the diel vertical migration of zooplankton in the Campeche area – controls the delivering of food particles to the corals. The Campeche cold-water coral province is, thus, an excellent example highlighting the importance of the oceanographic setting in securing the food supply for the development of large and vivid cold-water coral ecosystems., The research leading to these results has received support from the Deutsche Forschungsgemeinschaft (DFG) through funding of the WACOM – West Atlantic Cold-water Coral Ecosystems projects, grants HE 3412/17-1 and DU 129/47-1, and through providing ship time. A. Freiwald received funds from the Hessian LOEWE BiK-F Project A3.10, and G. P. Eberli acknowledges the donors of the American Chemical Society Petroleum Research Fund (grant no. 49017-ND8) for partial support of this research and the industrial associates of the CSL – Center for Carbonate Research at the University of Miami for additional funding. L. Matos has been supported by the FCT scholarship SFRH/BD/72149/2010.

With an extension of >40 km2 the recently discovered Campeche cold-water coral province located at the northeastern rim of the Campeche Bank in the southern Gulf of Mexico belongs to the largest coherent cold-water coral areas discovered so far. The Campeche province consists of numerous 20 to 40 m high coral ridges that are developed in intermediate water depths of 500 to 600 m. The ridges are colonized by a vivid cold-water coral ecosystem that covers the upper flanks and summits. The rich coral community is dominated by the framework-building scleractinia Enallopsammia profunda and Lophelia pertusa while the associated benthic megafauna shows a rather scarce occurrence. The recent environmental setting is characterized by a high surface water production caused by a local upwelling center and a dynamic bottom water regime comprising vigorous bottom currents, internal waves and strong density contrasts, which all together provide optimal conditions for the growth of cold-water corals. The strong hydrodynamics – potentially supported by the diel vertical migration of zooplankton in the Campeche area – drive the delivering of food particles to the corals. The Campeche cold-water coral province is, thus, an excellent example highlighting the importance of the hydrographic setting in securing the food supply for the development of large and vivid cold-water coral ecosystems.

In this paper we show that the development of the sediment architecture at the leeward toe-of-slope of Great Bahama Bank (Ocean Drilling Project Leg 166, Bahama Transect) during the last 6 Ma is not only a response to sea-level fluctuations, but also to major paleo-oceanographic and climatic changes. A major sequence boundary close to the Miocene/Pliocene boundary (dated at 5.6–5.4 Ma) is interpreted to reflect a major sea-level drop that was followed by a sea-level rise, which led to the re-flooding of the Mediterranean Sea at the end of the Messinian and increasing sea-surface temperatures at Great Bahama Bank. Distinct erosional horizons occurred during the Pliocene (dated at 4.6 and 3.3–3.6 Ma) related to sea-level change and the intensification of the Gulf Stream when the emergence of the Isthmus of Panama reached a critical threshold. The Gulf Stream brings warm, saline and nutrient-poor waters to the Bahamas. Starting at the Early–Late Pliocene boundary at 3.6 Ma this paleo-oceanographic reorganization in combination with enhanced sea-level fluctuations associated with the Late Pliocene main intensification in Northern Hemisphere Glaciation (since 3.2 Ma) led to (1) a gradual change from a ramp-type to a flat-topped type morphology, and (2) a change from a skeletal to a non-skeletal-dominated sedimentary system (mainly peloidal). Increased sea-level fluctuations during the second half of the Pleistocene led to an intensified high stand-shedding depositional pattern within the surrounding basins.