Taphonomic Comparison between the Late Pleistocene Key Largo Limestone and its Living Counterparts

Understanding transformation of unconsolidated sedimentary deposits to their liquefied components (rocks) is an essential problem in geology. For coral reef deposits, this transformation is especially complex. Coral skeletons are constantly modified --even while the organisms are still alive-- until they eventually become part of the geologic rock record as limestone. Coral modifications recorded in the geologic record consist of biological processes such as cavities produced by boring animals, incrustation by attached epibionts and internal sedimentation (cavities filled in by skeletal sediment from the reef surface). Other modification consists of physical abrasion and breakage of coral skeletons by storm-generated wave action. Some of these processes have been described but there has been no attempt to apply the results to a preserved coral reef limestone.

Taphonomy is the discipline that pertains to all processes responsible for the incorporation of any organism into the fossil record and the influence of these processes in the fossil record. It comprises all reactions that take between the death of an organism until it is discovered in the rock record. The southern Florida area offers an unparalleled opportunity to examine the preserved record of taphonomy in coral skeletons. Guided by observations of living counterparts of the same coral species, a better understanding can be gained of the taphonomy on the Late Pleistocene Key Largo Limestone, exposed on several islands of the Florida Keys. The study of the fossil limestone will provide information on the taphonomy of the coral skeletons. The dead coral of living reefs can provide the guidelines for interpreting these transformations.

Contact Information

Mr.
David Weinstein
University of Miami/RSMAS
4600 Rickenbacker Causeway
Miami, FL, 33149