North Atlantic coral reefs and giant carbonate mounds

Abstract

Since the pioneering visual documentation of deep-water coral reefs on the Porcupine and Rockall banks, performed by John B. Wilson, using a manned submarine (Wilson, 1979a, b), technology has come a long way. Today, the mapping of similar features along the northwest coast of Scotland, as performed by James Murray Roberts et al. (2003), is instead done using remote-sensing high-tech equipment, without having to put anyone in the water. This chapter mainly deals with the impressive and enigmatic giant carbonate mounds off Ireland. The story of their re-discovery in 1994 is told, when several survey vessels ventured there and found many different carbonate mounds and deep-water corals. In this chapter the Hovland, Magellan, Logachev, and Belgica Mounds are described and discussed. So are the strangest features of them all, the Darwin Mounds, located within the deep Rockall Trough, adjacent to a large field of pockmarks and adjacent to the Wyville-Thomson Ridge. The findings of the first ever scientific drilling of a modern carbonate mound is also reviewed and discussed. The chapter includes the description and discussion of carbonate mounds and coral reefs found in the Gulf of Cadiz and no less important, near numerous mud volcanoes on the continental slope off Morocco. Finally, giant carbonate mounds forming long, linear structures off Mauritania are also reviewed.