--> Abstract: Lithification of Bathyal Coral Deposits: The Mediterranean Plio-Pleistocene and the Lithoherms in the Florida Strait, by Juergen Titschack, Andre Freiwald, Fritz Neuweiler, Conrad Neumann, and Italo Di Geronimo; #90039 (2005)

Datapages, Inc.Print this page

Lithification of Bathyal Coral Deposits: The Mediterranean Plio-Pleistocene and the Lithoherms in the Florida Strait

Juergen Titschack1, André Freiwald2, Fritz Neuweiler3, Conrad Neumann4, and Italo Di Geronimo5
1 Erlangen University, Erlangen, Germany
2 Erlangen University,
3 Universite Laval, Quebec
4 University of North Carolina, Chapel Hill, NC
5 Università di Catania, Catania, Italy

During the last decades modern deep-water coral reefs constitute a major focus of bio-geological research. So far the fossilisation potential of these deposits is thought to be reduced because of an enhanced carbonate dissolution due to low temperature and a high pCO2. In the presented study we compare the microfacies of well-lithified bathyal coral limestones from Rhodes (Plio-Pleistocene, Greece), the Messina Strait (Plio-Pleistocene, Calabria, Italy), and the lithoherms of the Florida Strait (Late Pleistocene to Recent, east slope of the Little Bahama Bank). Although the general facies, faunal composition, and rock fabric is comparable in all of the study sites the various depositional geometries and complexities of fabric point to different depositional settings. The Mediterranean occurrences are bound to steep submarine palaeocliffs. This type of bathyal coral limestone contrasts with the one in the Florida Strait which is developed as 'mounds'. The more complex fabric of the Rhodes occurrences is due to multiple resedimentation events via debris falls along submarine cliff faces. In contrast the Messina and Florida Strait occurrences are in situ. All samples are well-lithified, fine-grained limestones. Cements are limited to thin isopachous bladed spars in intraparticle and interparticle pores. Centimetre-sized consolidation horizons separating different sediment zones (especially prominent in the samples from Rhodes) point to an early marine consolidation of the coral-bearing mud- to wackestones, possibly due to a matrix-lithification by automicrite precipitation. Irrespective of the depositional differences all studied samples went through a process of constructive early marine diagenesis that resulted in a consolidation of the fine matrix.

AAPG Search and Discovery Article #90039©2005 AAPG Calgary, Alberta, June 16-19, 2005