The Carbonate Project: Mid-Latitude Carbonate Systems — Complete Sequences from Cold-Water Coral Carbonate Mounds in the Northeast Atlantic
Andrew J. Wheeler1, Andre Freiwald2, Dierk Hebbeln3, Rudy Swennen4, Tjeerd van Weering5, Henk de Haas5, and Boris Dorschel1
1Geology & Environmental Research Institute, University College Cork, Cork, Ireland
2Institute of Paleontology, University of Erlangen-Nuremberg, Erlangen, Germany
3MARUM - Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
4Dept. Geography-Geology, Catholic University of Leuven, Leuven, Belgium
5Royal NIOZ, Texel, Netherlands
Up to now, very little is now about the internal structure and diagenetic processes operating within cold-water coral carbonate mounds which have been identified in abundance on continental margins both at the seafloor and in seismic sequences. The reservoir potential for these features is poorly constrained. Other scientific challenges exist e.g. the carbonate stored in carbonate mounds has not been considered in any global carbonate budget or linked to any global carbon budget involving greenhouse gases.
Investigations reveal that all mounds possess different growth histories depending on the environmental setting and the involved faunal associations. Unfortunately, existing cores only penetrated the upper few meters of the mounds thus limiting mound research to the very late stage of mound development. Access to the longer sequences preserved in giant carbonate mounds was overcome in May 2005 when the IODP Expedition 307 (Porcupine Mound Drilling) recovered complete sedimentary records from one 155 m high “Challenger Mound” in the Porcupine Seabight west off Ireland. EU-FP projects have revealed late stage history of giant mounds in different settings showing that different mounds respond in different ways to environmental forcing factors with no one mound being typical of all.
CARBONATE will drill complete sequences through a number of mounds in differing environmental settings using the portable drill rig MeBo (University of Bremen). By understanding how biogeochemical processes control the development of these carbonate mounds and their response to climate change, we will make an important step in quantifying their role as mid-latitude carbonate sinks. In the end, a better understanding of the processes involved in mound formation and development may also result in new views on fossil analogues many of which are less accessible hydrocarbon reservoirs.
AAPG International Conference and Exhibition, Cape Town, South Africa 2008 © AAPG Search and Discovery